CopyiightN?_ COPYRIGHT DEPOSIT fa H < The Theory and Practice OF Working Plans (FOREST ORGANIZATION) BY A. B. RECKNAGEL, B.A., M.F. it Professor of Forestry Cornell University FIRST EDITION FIRST THOUSAND NEW YORK JOHN WILEY & SONS London: CHAPMAN & HALL, Limited 1913 Copyright 1913 by A. B. RECKNAGEL v •!»< \*> % PEESS OF THE PUBLISHERS PRINTING COMPANY, NEW YORK, U. S. A. ©CI.A33 2657 fa) t PREFACE This book does not pretend to present any original theories of Forest Organization, but merely the best of European efforts along this line adapted to the present needs of American forestry. The necessary data were gathered in the course of a year's study abroad, and, in their application, the experience gained in five years of similar work for the forest service in various parts of the United States was constantly kept in mind. The theoret- ical part has, therefore, been reduced to the minimum; simi- larly, the description of such intensive methods of regulating the yield as that by area and volume in periods has been merely sketched for the sake of completeness, since its application to America is of the far distant future, if ever. In a word, while sacrificing nothing to the completeness necessary in a text- book, the aim has been to make the book of value not only to the student, but also to the practising forester, and hence theory has in each case been subordinated to practice. x It will be ample reward for the time and labor spent, if this book takes its humble place in the growing list of American text-books on forestry. Grateful acknowledgment is made to those who so unself- ishly assisted in the collection of the subject-matter. A. B. RECKNAGEL. Dresden, September, 19 12. Ill CONTENTS PAGE Preface iii Introduction, xi Value and Need of Working Plans, xi Scope of Working Plans xi Sphere of Working Plans xii PART ONE Foundations of Working Plans chapter I Preliminary Basis PAGE Section I. The Normal Forest and its Attributes, i The Increment, i The Growing Stock, . . . . • . 4 Distribution of the Age Classes, 4 Section 2. Collection of Data. — Reconnaissance, 8 Preliminary Work, , „ 8 Survey of Area . . 9 Timber Estimates, 10 Requisites, 10 Base Lines, . 10 The Strips, ..12 Reconnaissance Estimates 14 Topographic Notes, „ 16 Time of Survey and Estimate, 16 Use of Yield Tables, ...17 Cost, . . 17 Forest Description 17 Division of Area, 20 Designations of Divisions, 23 Boundaries of Divisions, 23 Maps and Tables, „ . . 26 General Stand Table, 25 Age Class Table, , 31 V VI CONTENTS PAGE Section 3. Determination of Methods of Treatment 33 Governing Conditions, . . . 33 The Unit of Regulation, 33 Silvicultural Method of Management, 35 Object of Management, 37 The Rotation, 38 CHAPTER II Regulation of Yield Definition, „ „ ,42 Section 1. Determination of Yield, 43 By Area (1), 44 By volume. Von Mantel's Method (2), 47 Methode de Masson (3), 49 By Current Annual Increment (4), 49 Formula Methods: Austrian Formula (5), .... 52 Karl's Method (6) 55 Hundeshagen's Method (7), . . 59 Breymann's Method (8), ... 61 Heyer's Method (9), . . . . . 63 Summary and Comparison of the Formula Methods, . 65 French Method (10), 66 Indian Method (11), > 72 Diameter Class Method (12) 75 By Area and Volume. Russian Method (13) 78 Direct Method (14), . 81 Hufnagl's Method (15) 82 The Stand Method (16), ....... 84 The Period Methods (17), 89 Review of the Methods of Determining the Yield, 94 Section 2. Distribution of Yield 96 Selection of Stands to be Cut 97 Mapping of Stands to be Cut, 98 Cutting Series, 99 Plan of Cutting, 100 General Cutting Plan, 101 Annual Cutting Plan, . 103 Section 3. Regulation of Yield in Special Cases 104 I. Regulation of Abnormal Forests, . 104 II. Regulation of Transition Forests, 106 III. Regulation of Wood-lots, .... 108 IV. Regulation of Turpentine Forests, 108 CONTENTS VI 1 CHAPTER III The Working-Plan Document PAGE Section I. Contents and Form, 113 1. Orientation, 115 2. Foundations, 116 3. Recommendations, 119 4. Regulation, 121 Section 2. Outlines for Working Plan, 122 A. Prussian Outline, 122 B. Saxon Outline, 124 C. American Outline (suggested). Complete Forest Plan, . . . 124 Section 3. The Planting Plan, 128 Annual Planting Plan, • 130 General Planting Plan 132 Section 4. Control and Revision of Working Plan, 133 Control Book, 134 PART TWO Practice of Working Plans CHAPTER I In Europe PAGE Section 1. Germany 137 I. Prussia, 137 II. Bavaria, 147 III Saxony, 159 IV. Wiirttemberg, 163 V. Baden, 164 VI. Alsace-Lorraine, '. . 167 Section 2. France, 171 Division of Area, 172 Method of Determining the Yield, 173 Distribution of the Periodic Cutting Areas, 175 Determination of the Allowed Annual Cut, 176 Section 3. Austria, 177 Division of Area, 180 Estimates and Forest Description, 182 Determination of the Yield, 185 Control and Revision of the Working Plan, 186 Section 4. Resume, 187 VI 11 CONTENTS CHAPTER II In America PAGE Section I. Early Beginnings, 190 Section 2. The New Reconnaissance, 191 Current Outline for Forest Working Plans, 192 Section 3. Present Procedure, 201 Forest Plans, 202 Preliminary Plans, . 203 Working Plans, 208 Annual Plans 211 Outline for the Plan of Silvicultural Management, 213 Timber Estimates 213 Forest Types, 214 Object of Management, 215 Silvicultural System, 215 Regulation of Yield, 216 Regulation of Cut, 216 Policy 217 Stumpage Rates, 217 Utilization, 218 Timber Business Statistics, 220 Planting, 224 Timber Reconnaissance, 226 Investigations, 226 ILLUSTRATIONS Plate I. — Cutting Series and Compartment Lines in Spruce, Saxony. Frontispiece PAGE Plate II. — A Reconnaissance Survey Party, Florida, 10 Plate III. — A Reconnaissance Survey Camp, Florida, . . . ". . 16 ^ Plate IV. — Fig. I. A Compartment Regenerated by Shelterwood Cut- ting, Baden. Fig. 2. A Compartment Regenerated by Border Cutting, Wurttemberg, 36 Plate V. — Road Forming a Compartment Boundary Line, Saxony, . 160 Plate VI. — A Burned Area, Forming a Subcompartment, Arizona, . . 2081/ FlG. I. — Sketch Map of part of a Block, showing Compartments, Sub- compartments, Age Classes, and Cutting Series, 27 Fig. 2. — Turpentine Regulation: Number of Crops Operative An- nually, 112 V IX INTRODUCTION VALUE AND NEED OF WORKING PLANS Systematic forest management demands that the yield in timber or other forest products be regulated according to time and place. This apportioning of the yield is the sphere of Forest Organization through its instrument, the Working Plan. Forest Organization is co-ordinate in importance with Silvi- culture, Forest Protection, and all the other major branches of the science of Forestry. It makes use of them all and combines their several teachings into a harmonious whole — the forest properly adjusted. SCOPE OF WORKING PLANS In its broadest sense a complete Forest Plan deals not only with Silvicultural Management of the timber resources, but may cover any or all of the following subjects: i. General administration. 2. Silvicultural management. 3. Grazing management. 4. Permanent improvements. 5. Forest protection. 6. Uses of forest land. Since the prime object of any forest is the growing of timber, the silvicultural management is the most important; it is also the most difficult. The present work will, therefore, confine itself to this phase of the complete forest plan. The French call this phase "Amenagement" — "Management"; the Germans call it "Forsteinrichtung"— "Forest Adjustment" or "Forest Organ- ization." The latter title seems preferable since "management" xi ill INTRODUCTION' is commonly considered to include Mensuration, Valuation, etc.* Unfortunately the title ''Working Plan'' has been long used in America to designate not only the document, but the whole subject of Forest Organization. However, as Dr. Fernowsavs:f "It is difficult to eradicate poor terms once in the world." vet "we must admit also the use of synonyms, for. after all. language is partly a matter of taste and only partly of rule." The word "Working Plan'' has. therefore, been retained for the present, but "Forest Organization" is used synonymously with it to designate the subject of regulated Silvicultural Management. SPHERE OF WORKING PLANS The working plan is not confined to such forests as are managed with the idea of a sustained yield, but is equally adapted to the exploitation forest; i.e.. forests which are to be logged within the next ten or twenty- years. As in every- other business the advantages of systematization are obvious; the working plan secures these advantages. At the same time it is usually to the interest of the owner to leave the tract in as favorable a condition as possible for future growth without the undue expenditure of time, timber, or money. The working plan secures this by so organizing the logging operations that the natural reproductive powers of the forest are brought into full play instead of being nullified by the fortuities of haphazard and often unnecessarily destructive logging. The sphere of Forest Organization therefore embraces all forests and is applicable to all classes of owners, large and small. "A Classification for Forestry Literature," Yale Forest School, Bul- letin I, 1912. t "F. Q., M Vol. IX., Xo. 3, p. 427. PART ONE FOUNDATIONS OF WORKING PLANS FOUNDATIONS OF WORKING PLANS CHAPTER I PRELIMINARY BASIS SECTION ONE THE NORMAL FOREST AND ITS ATTRIBUTES At the very root of Forest Organization lies the idea of a Normal Forest; that is, one which has a normal distribution of the age classes and a normal increment; these two factors will, of themselves, result in a normal growing stock. Such a forest probably does not exist; it is merely a theoretical ideal towards which to strive. Assuming, therefore, that every forest is more or less ab- normal, it is necessary to determine the degree of abnormality in the following directions: i. Increment. 2. Growing Stock. 3. Distribution of the Age Classes. In this connection it should be noted that while normality in 1 and 3 of themselves result in normality in 2, the reverse is by no means the case. A normal growing stock may exist in a forest with only a single age class. Valuable as its determina- tion is, therefore, it should never be used as the sole criterion of regulating the yield. The Increment The determination of the increment is the province of Forest Mensuration; without trespassing on this subject, so admirably A THE THEORY AND PRACTICE OF WORKING PLANS covered in Mr. Graves' textbook,* it is worth while to consider the matter solely in its relation to Forest Organization. Not every method of regulating the yield requires the deter- mination of the volume increment; e.g., the Method of Von Man- tel or the Methode de Masson. Again, it is possible to regulate the yield by increment alone (Hufnagl's Method). But, as is pointed out in Chapter II, most methods of regulating the yield require a determination of the increment. The normal increment is that given in yield tables: this is required for several of the "formula methods." Where the real increment is to be taken from yield tables, the values given in the table must be reduced by the actual factor of density, since yield tables are always for fully stocked stands. Where yield tables are not available, the increment must be determined on the ground, either by applying the increment per cent of representative trees of the stand, or else by calipering sample areas and figuring their increment by means of diameter- growth and diameter-volume tables. The former (and yield tables) is better for nearly even-aged stands; the latter method for all- aged stands. Where diameter-growth tables are lacking, stump analyses can be made. For determining current annual increment the use of an increment borer is deserving of wider popularity than it has heretofore enjoyed in America. Where no increment borer is obtainable, the representative trees, selected according to any of the standard methods (Draudt, Urich, etc.) can be cut into at breast height and the rings on the last inch of radius counted on the horizontal under-cut. Schneider's formula then applies: 400 p = —r (or 450 or 500 according as the height-growth of the tree is poor, average, or good), * "Forest Mensuration," Henry Solon Graves. New York, John Wiley & Sons. THE THEORY AND PRACTICE OF WORKING PLANS 6 where n = number of rings of annual growth in the last inch and d = diameter breast high, in inches. The growth per cent must always be translated into figures of actual volume. For example: A spruce tree 28 inches in diameter at breast height, of average height-growth, shows 8 rings in the last inch, bored at breast height. The increment per cent according to Schneider's formula is Assuming a stand of 2,400 feet board measure per acre, the volume increment (current annual) would be, if this were a sample tree: 2,400 X 2 — = 48 board feet per acre per annum. 100 Whether the current annual or the mean annual increment is to be determined depends on the Method of Regulating the Yield which is to be adopted (Chapter II). However, in general it may be said: The "formulae methods" usually require the determination of the mean annual increment. Methods by Area and Volume usually employ the current annual increment pro-rated for the next decade or two decades. Indeed, for the "Period" Methods it usually suffices to determine the increment of only such stands whose age is more than half the rotation f -J or even only those of the two highest age classes of, say, 20 years each. In either case it is not usually necessary to determine painstakingly the exact increment of each stand, but rather to correctly approx- imate the increment in each Working Figure — i.e., the unit area for which the yield is to be regulated; for it is evident that in comparison with the volume of merchantable timber the increment is a relatively small amount. It is a useful fact that in stands approaching maturity (not overmature) the mean annual and current annual increment remains virtually the same 4 THE THEORY AND PRACTICE OF WORKING PLANS for about ten years; since the former is simply the volume divided by the age ( — J, a simple way is thereby opened to approximate the current annual increment in mature, even- aged stands. The Growing Stock The normal growing stock is expressed by the formula: ri nv = — 2 where nv = normal volume of growing stock, r = rotation, and i = the normal increment, nv can also be determined directly from yield tables constructed by measurements of fully stocked stands. That the normal volume is possible even with abnormal arrangement of the age classes is clear if one considers a unit of area covered with a normal steplike gradation of the age classes, the same area half bare and half stocked with trees whose age equals r (the rotation), or again, the whole area stocked with trees whose age equals }4r. In each case by the formula nv = — the growing stock would be apparently normal, yet true normality exists only in the first case. Distribution of the Age Classes The correct distribution of the age classes is theoretically like a series of equal sized steps, growing higher towards the prevailing storm direction. However, this theoretical ideal is never achieved; it suffices that each age class has an approximately equal representation on the area which is to have a sustained yield; in fact, without a fairly even distribution of the age classes sustained yield on a given area is impossible. Twenty years is commonly taken as one age class, though sometimes 10 and sometimes 36 years is used. In any case the rotation must be a simple multiple of the age class. It is customary to number the age classes from I up, beginning with THE THEORY AND PRACTICE OF WORKING PLANS 5 the youngest.* Thus for an 8o-year rotation there are four age classes of twenty years each; a fifth age class would contain all stands older than r (the rotation). Where stands are fairly even-aged, but conditions are too extensive to permit the exact assignment to definite age classes, the general classification into: merchantable near merchantable intermediate young growth will serve the purpose. It is of the utmost importance to get some conception of how the age classes are distributed. If it is possible, the age should be determined by counting the annual rings on recent stumps, but in default of this it is useful to note the age class roughly as: overmature (more than rotation age) M mature (of rotation age down to yi thereof) Y young (from lowest age to y 2 rotation) The perfect selection forest is, of course, all aged and hence has no age classes, or rather all age classes are inextricably intermingled. But where the age differences are not to exceed K or % of the rotation, the stand can be classified according to its average age, or, more exactly, according to the proportion of space each age occupies. For example: 320 acres of spruce might contain 160 acres of trees 70 years old, 100 of trees 60 years old, and 60 acres of trees only 40 years old. The average age here would be 61 years; for: 160 X 70 + 100 X 60 -f- 60 X 40 =61 years. 320 Where, in uneven-aged forest, the age classes are so inter- mingled that they cannot be distinguished by area but only by volume (from the diameter-classes in the estimates, see * In Prussia this is reversed, I. is the oldest age class. 6 THE THEORY AND PRACTICE OF WORKING PLANS volume .. ,, Section 2), the average age = the increment > g -g-> lf the uneven ' aged forest has three main age classes: 100 year class with 2,000 feet board measure 60 " " " 1,200 " 5 o " " " 800 " 2000 + 1 200 + 800 then the average age would be — — g^ - 7M years. 100 60 50 The ordinary selection forest would show the following dis- tribution of ages by area: E.g., 900 acres of selection forest with a rotation of 150 years and a cutting cycle of 30 years would normally contain— -5 age classes, not distinct in space but in area, as follows: , , 900 x 30 . Trees 1- 30 years old —^3 — = l8 ° acres » 3I _ 60 " " " =180 " " 61- 90 " " " =180 " " 91-120 " " " =180 " " 121-150 " " " =180 " Total, 900 acres A convenient way to express the age limits and average age 50 — 100 in an uneven-aged stand is by the expression - — — where, m the example above, the age varies from 50 to 100 years and the average has been determined as 71 years (strictly 71.4 years). Where the average age has not been arithmetically determined the approximate age figures will, at least, serve as a valuable O-M guide. Or even the letters 0, Y, M may be used, e.g., —q- would be a stand Mature to Overmature with the average Overmature, i.e., in excess of the rotation age. THE THEORY AND PRACTICE OF WORKING PLANS / Nor should it be forgotten that certain species, such as fir and spruce, often withstand decades of suppression during which their growth is almost nil. In determining their age this "core of suppression" should, therefore, be disregarded. Areas that are being regenerated by shelterwood methods fall into two age classes, divided according to the per cent of density of the original stand. For example, a shelterwood cutting in a 90-year-old stand covering 200 acres of which only 40 per cent of the stand remained uncut would be apportioned : 80 acres to the higher-age class and 120 acres to the lowest or to the "blanks" if no reproduction was on the ground. Where less than 20 per cent of the original stand remains on a cutting area or burn and the density of stocking is less than .3 (Section 2) and there is no reproduction the area is, temporarily at least, classed with the "blanks." The age classes are differentiated by species only if there is a marked difference in their value. There are two graphic ways of comparing the actual with the normal distribution of the age classes. One is by plotting the normal and the actual area of each age class on cross-section paper, using the co-ordinates for age and the abcissae for area. The normal distribution will, of course, be a straight line; the actual a zigzag, now rising above, now falling below the hori- zontal line of normality. The other method is that of rectangular blocks, the normal age classes being equal-sized and placed next to the unequal blocks showing the actual size of the various age classes. It is always of advantage to compare the real and the normal age-class distribution; for it is a criterion of a sustained yield and, in conjunction with the increment, determines the degree of approach toward a normal forest. 8 THE THEORY AND PEACTICE OF WORKING PLANS SECTION TWO COLLECTION OF DATA— RECONNAISSANCE Here again Forest Organization touches upon the domain of Forest Mensuration and, in part, of Engineering. Hence only the salient points affecting the Working Plan will be treated. Preliminary Work Before the field work is begun, all available data should be gathered from the records, along the following lines: i. Area and boundaries of forest. 2. Best existing estimates of timber. 3. Approximate distribution of species. 4. Salient topographic features. 5. Past cuttings and their results; stumpage prices. 6. Classes of material utilized; prices obtained; market con- ditions. 7. Previous working plan or previous silvical studies; vol- ume, growth, or yield tables. 8. Best maps available. Armed with these data, the Forest Organizer should then make a preliminary trip over the forest so as to gain a general familiarity therewith and the better to formulate his plan of •campaign. Wherever possible, he should be accompanied by the owner, the administrator, or both. A conference should always be had between the owner or administrator, or both, and the Forest Organizer. The wishes and objects of the owner are basic in outlining a plan of silvi- cultural management and determine what data are requisite and what degree of detail is necessary in securing these data. The permissible cost of field work should also be decided. It is well if tHe results of this conference are put in writing and the docu- ment signed by each of the participants. the theory and practice of working plans 9 Survey of Area A good map is an essential part of every Working Plan. The map need not be elaborate, but it must be accurate. Where the land involved has not been surveyed, this must form a part of the field work, though it can often be done in conjunction with the estimating. In every case, reconnaissance involves at least the retracement of the principal land lines and their fixation on the ground and on the map. Especial attention must be given to the boundary lines. It is very serviceable to post boundary and interior corners with fire warnings or similar placards, in pathless forests. These are most helpful in indicating the position of corners, especially if they are stamped with rubber stencils and indelible ink to show what corner it is. Thus where the land is sectionized, the section corner would be posted and perhaps also where an im- portant section or township line crossed a much-traveled road or trail. The object is to make the results of field surveys or retracement of old survey lines available not only on the map, but on the ground. The extent to which topography should be shown depends on the uses of the map. Where a detailed plan of logging is to be included, the topography must be shown in detail. For purposes of ordinary forest organization it suffices to show all drainage, all roads and trails, all houses, barns, and other "cul- ture," and the topography in contours of ioo-foot interval sketched in from aneroid barometer traverses. In level country contours serve no useful purpose. In the matter of topography the object is to get a good working medium for orientation and for the subsequent division of the area. The scale of the map must depend on the size of the area, the wealth of detail, and the intensity of the proposed manage- ment. Ordinarily a scale of i or 2 inches to the mile for the general map is quite sufficient. Where the forest is very large it is well to have a small scale location map, and then larger scale maps showing the various parts of the forest in greater detail. 10 THE THEORY AND PRACTICE OF WORKING PLANS No survey of the area — and no forest map — is complete which does not include a delineation of the forest types. This is usually done in conjunction with the estimating, but its im- portance must be emphasized here. Simplicity in type dis- tinctions is essential for clearness. Only those type differences should be recognized which are sufficiently striking as to be recognized instantly by every trained eye. Ordinarily, per- manent types alone should be regarded, but often transitory types — e.g., aspen on old burns — must be recognized, since they demand a different treatment. Minor differences should never, for the purposes of a Working Plan, be made the basis of type distinction. The mapping of all cut-over or burned areas, of swamps, barrens, etc., is a part of every forest survey. Timber Estimates Requisites. — Without encroaching on the subject of forest mensuration, the requisites of the timber estimates for purposes of the Working Plan are: i. Amount and species of timber. 2. Class of timber (saw timber, cordwood, etc.). 3. Condition of timber (soundness). 4. Approximate age of timber. For purposes of combining the survey with the" timber esti- mate, the strip method of estimating is undoubtedly the best. From a definite base line — such as a section boundary or, if in unsurveyed or very rough country, a base line previously run out — the strips are run out at right angles, at definite in- tervals. Base Lines. — The section line serves as an excellent base, especially in fairly level country. Rough topography or the lack of suitable survey lines as a base make it necessary to establish base lines in advance of the actual estimating. They should be located in valley bottoms, along roads, or elsewhere so that they can be easily re- traced; at the same time they give a preliminary PLATE II. A Reconnaissance Survey Party, Florida. THE THEORY AND PRACTICE OF WORKING PLANS 11 topographic control. The distances must of course be measured accurately either by chain or tape or by stadias. The use of stadia — involving a mountain transit or a telescopic alidade — is advisable only in fairly open country or for the primary base lines. The chain or tape is much handier in timbered country; pacing is not accurate enough for this purpose. Beginning at some known point, or at least tied thereto by definite triangulation, the base line system is developed over the whole forest like the stem and branches of a tree. The number of base lines must depend on the intensity of the work ; better fewer and accurate than many and slipshod. A traverse board and open sight alidade are excellent for base-line work unless the timber is too dense ; then chaining alone is possible, and the notes must be plotted not only upon return to camp, but immediately, in the rough, so as to determine where the equidistant survey stations are to be established. For the base line traverse will necessarily be a zig-zag and the survey stations must be exactly equidistant. They are usually marked with a stake and a pile of stones or a blaze, scribed or blue-penciled with the number and the elevation of the station. For purposes of identification it is well to place the station close to some road, trail, stream, or other topographic feature. The elevation is determined by aneroid barometer readings carried from some point of known elevation. Where transit or telescopic alidade are used it can also be determined by the vertical angles. The crossings of all roads and trails, of creeks, etc., are noted, either directly plotted on the traverse table or else entered in the note-book; the elevation at these crossings is also noted. If the forest is so large that the estimating will require several seasons, only so much of the base-line work need be completed in advance as will be used in that season. However, base-line work can often be done to advantage several months before the detailed estimates are begun. Wherever possible, the Forest Organizer should himself be in charge of the base-line work. Three men constitute the ordinary base-line crew; two will suffice at a pinch, though it is 12 THE THEORY AND PRACTICE OF WORKING PLANS better to have two to chain and one for the traverse board or to enter notes, take aneroid readings, etc. The Strips. — The estimate strips should always run across the topography; only in that way will average conditions be secured. The size of the crew depends on the method of esti- mating employed. The ordinary valuation survey crew consists of two caliper men, and a head and a rear chainman. The former runs the compass, the last named takes notes on topography and elevation and enters the diameters breast high as called out by the caliper men. Each strip is usually one chain wide. Where the strip is not chained, the crew can be reduced to three, or even two, the compassman to pace and keep notes, two (or one) to caliper. Where trained men are used, calipering is seldom necessary; here two men — one to pace and keep notes, one to estimate diameters — suffice. In open timber the strips can be widened to one chain on each side of the line. One man can run a strip, but he can scarcely manage com- pass, aneroid, note-book, and estimate all at the same time. Either he must make an ocular estimate of the whole stand or else confine himself to quarter-acre (or similar sized) sample areas at definite intervals. Only in cases of need is this sample- area method advised; it is usually better economy to use a two or more man crew. The work goes better, the men check each other's judgment and, finally, in case of accident, the single man is not left helpless. The strips must gridiron the forest. The interval between the grids depends on the purpose of the work. For a reliable esti- mate 5 to 10 per cent of the area should be covered. This means : For 5 per cent of area: chain wide strips 20 chains apart. " 5 " " " strips two chains wide, 40 chains apart. " 5 " " " Four >^-acre sample areas, 2*4 chains apart on strips 20 chains apart THE THEORY AND PRACTICE OF WORKING PLANS 13 For 10 per cent of area chain wide strips 10 chains apart. " 10 " " strips two chains wide 20 chains apart. " 10 " " Four X _acre sample areas, 2^ chains apart on strips 10 chains apart. A very practical way of recording the estimates is by 3 -inch diameter classes, beginning with the smallest merchantable diameter, supposing this to be 11 inches, as follows: D. B. H. SPECIES inches Pine Spruce Fir Etc. 12 15 18 21 24, etc Poles Saplings Seedlings Seedlings are all trees under 5 feet in height; these are usually counted on a quarter-acre circle at the end of every ten chains or so, to supplement the notes on reproduction (see below). Saplings are from 5 feet in height to, say, 6 inches diameter breast high. Poles are over, say, 6 inches diameter breast high up to the minimum merchantable diameter. Poles and saplings are counted and tallied just like the larger timber. While the strip estimates, in combination with volume tables, usually give more accurate results than an ocular estimate, the greater expense of the former and the longer time required to cover a given area often decide in favor of the latter, expecially where a rough estimate suffices and data on diameter classes are not requisite. Various methods of ocular estimating have been devised ; for purposes of Forest Organization the Method of Reconnaissance 14 THE THEORY AND PRACTICE OF WORKING PLANS Estimating practised by the Federal Forest Service since 1907 is probably the best.* Reconnaissance Estimates. — This method is briefly as follows: Beginning at a known point, the estimator paces 10 chains, compass in hand, in a straight N., S., E., or W. line. This places him in the centre of a 40-acre square. For example, if the initial point were 10 chains west of the southeast corner of Section 6, the estimator would pace 10 chains due north and thereby be in the exact centre of the S.E. X °f the S.E. % of Section 6. Here the estimator glances carefully around and "sizes up" the timber to the best of his ability. However, he makes no permanent entry in his note-book until, having gone a further 10 chains in the same direction, the boundary of the 40-acre square is reached. The last 10 chains t may have revealed conditions necessitating a change in the original estimate; the estimator now sets down the estimate by species for the entire forty directly in M. feet board measure or cords or other unit. A diagrammatic blank is provided for the purpose. He also notes the general age of the timber and designates it for the forty by the letters: O for overmature — older than the rotation age. M for mature — more than half the rotation age. Y for young — less than half the rotation age. The intermediate grades O-M and Y-M are also used. This classification and the estimates are for timber above the minimum merchantable diameter; below this diameter, the "young growth" or "reproduction" is designated for the forty by the letters: G for good — enough to fully restock the area. F for fair — enough to half restock the area. P for poor — practically nothing wherewith to restock the area. The intermediate grades G-F and P-F are also used. * For detailed description see "Proceedings Society of American Forest- ers," Vol. IV., No. 1. Reprinted Yale Publishing Association, 1909. See also, for practical workings, cost, etc., "F. Q.," Vol. VIII. , No. 4, pp. 415 to 418. THE THEORY AND PRACTICE OF WORKING PLANS 15 This process repeats itself for each forty. For purposes of checking, the estimator ties his line to any known points. E.g., in the above example, after having run 40 chains or to the middle of the Section, the estimator ties to the E. }i corner thereof; again, after having run 80 chains or to the northern section line, the estimator ties to the N.E. section corner. Similarly base- line corners are tied to, and the aneroid elevations checked. In tying to surveyed section corners Mr. "J. H.' Allison of the Forest Service has, from many years of field experience, evolved an excellent shortcut. E.g., in the example cited above, the estimator starts directly from the S.E. section corner and runs 14. 1 chains N. 45 W., which places him in the centre of the S.E. J4 °f tne S.E. %. Thence he runs due north 10 chains at a time. The twentieth chain places him in the centre of the N.E. % of the S.E. %. Thence he runs 14. 1 chains N. 45 E. to the E.X corner and ties thereto. Thence again 14. 1 chains N. 45 W. to the centre of the S.E. % of the N.E. X, thence 10 and again 10 chains due north to the centre of the N.E. yi of the N.E. yi, thence 14. 1 chains N. 45 E. to the N.E. section corner. To go back southward through the section — from the N.E. section corner the estimator runs 20 chains due W., thence S. 45 W. 14.1 chains to the centre of the N.W. >^of the N.E. }{, thence due south, reversing the process previously described (except that there is no centre corner to tie to), and so reach- ing after 60 chains due south, the centre of the S.W. yi of the S.E. %, and thence 14. 1 chains S. 45 W. to the south ^ corner of the section. Obviously, the distance between the strips must be varied according to the character of the timber traversed. Very open stands may permit strips 40 instead of 20 chains apart and estimates by quarter sections; in dense stands the distance may have to be shortened to 10 chains and the estimate made by 10-acre units. The method remains the same. The criterion is the area which can be looked over by the estimator without slighting any important part. In this method the estimator should be an experienced judge 16 THE THEORY AND PRACTICE OF WORKING PLANS of timber; in any case he should check his judgment by frequent sample areas whose contents have been accurately determined by calipering each tree; thorough drills, monthly, on sample "forties" will serve to test and bring up to standard the judg- ment of each man in an estimating crew. Topographic Notes. — Besides the timber estimating, it is a valuable feature of all strip systems that the opportunity is offered to get excellent data on topographic features. The estimator or tally man carries an aneroid barometer and notes the elevation at each stream, divide, or similar feature ; also at each corner to which he ties. Streams, ridges, roads, trails, etc., are sketched by him in a suitable note-book so as to show the exact point at which these features were crossed and their trend for a short distance to either side of the survey line. The same method applies to burned and cut-over areas. The boundaries of these and of the forest types should be noted where they are crossed and their trend for a short distance to either side of the survey line. These data should be sketched in on blanks or note-books provided for the purpose. Time of Survey and Estimate. — The "field season" — i.e., that season when field work can be accomplished with the minimum of climatic difficulties — is usually the best for the work of estimating and mapping. In mountainous countries and in northern latitudes, this means the summer months; in southern latitudes winter is often preferable because of the excessive summer heat. Even in mountain regions the winter season may sometimes be chosen because the forest personnel is usually less heavily burdened with work in winter than in summer. That winter work is entirely feasible, if snowshoes or skis are used, is demonstrated by the winter reconnaissance in certain mountain forests of California.* One advantage of winter work is the ease with which the compassman's tracks can be followed by the cruisers and used by them as a check on the width of the estimating strips. * See "Winter Reconnaissance in Californian Mountains," R. F. Ham- matt, "F. Q.," Vol. IX., No. 4, pp. 557-562 PLATE III. A Reconnaissance Survey Camp, Florida. THE THEORY AND PRACTICE OF WORDING PLANS 17 Use of Yield Tables. — The estimating of timber by means of yield tables unfortunately finds little or no application in America because of the lack of suitable tables. Yield tables are constructed for even-aged fully stocked stands of a single species for various site qualities. The age is usually given in five- or ten-year intervals. European yield tables are separated for final and intermediate yield (thinnings) and total. Normal yield tables preponderate, but real (empirical) yield tables are used as makeshifts. The methods of making yield tables is the province of Forest Mensuration, but for purposes of Forest Organization the data should comprise at least: Age, Yield, Current and Mean Annual Increment for each Site Quality (I to V, see "Forest Description," below). The use of Yield Tables requires the determination in the field of the following data (presupposing nearly even-aged stands): Age, Site Quality, Density of Stocking. The corre- sponding value for the age and site quality is read directly from the yield table and this multiplied by the factor of density (i.o to o.o) — see "Forest Description," below. Where there are several species in the stand, the percentage of each is determined and the corresponding value in the various yield tables mul- tiplied thereby; these values are then added and their sum mul- tiplied by the factor of density (i.o to o.o). Cost. — The cost of estimating by the strip methods averages between the following figures: Summer work 1.5 to 6 cents per acre Winter work 3.0 to 6 cents per acre Forest Description It is of the utmost importance for the W T orking Plan that the silvical data secured in gridironing a forest be made a matter of record. In order that the observer may put down his observa- tions while they are fresh in his mind it is well to provide a note- book or blanks with appropriate headings, such as: Character of Forest. — Even-aged, all-aged, even-aged in 2 18 THE THEORY AND PRACTICE OF WORKING PLANS groups, etc., average age. Component species in percentages of chief timber trees. Average Site Quality. — (I to V of which I is the best, V the poorest; intermediate grades are expressed thus: I/II, IV/V, etc. The usual criterion for determining site quality is the height growth; tables of height growth serve as a useful guide in this respect. Until the eye is trained, some hypsometer measurements are advisable. Comparative volume growth is also a useful guide to Site Quality. Density of Stocking. — (i.o to o.o in decimals, of which i.o is the fully stocked stand, o.o is the vacant or barren area.) The density is usually determined by the crown cover, although this varies with the species. For example, a fully-stocked stand of Western yellow pine has an altogether different crown density from the fully stocked stand of spruce. The best judgment of the observer is required in this and every other phase of forest description, if the data are to be of real value and use and not merely "guesswork." Both Site Quality and Density of Stocking have their explana- tion in natural causes which the observer should try to determine and to place under one or several of the following headings: Cuttings. — Apparent date, purpose, silvicultural method used, if any, present condition with especial regard to whether the cutting area is restocking satisfactorily. Burns. — Apparent date, cause, present condition with especial regard to whether the cutting area is restocking satis- factorily. Rock. — The determining characteristics, such as "granite," "shale," etc. Soil. — The simple name — "sandy loam," "clay," etc. Ground Cover. — Weeds, grass sods, etc. Whether sufficient to prevent natural reproduction. Undergrowth. — Character of undergrowth, brush, etc. Wheth- er sufficient to prevent natural regeneration. •Young Growth. — Seedlings, saplings, poles, approximate proportion of each, whether they occur scattered uniformly THE THEORY AND PRACTICE OF WORKING PLANS 19 over area, or patchy and groupwise. Is the young growth now present sufficient to restock the area. ''This does not mean," as Mr. Zon points out,* "a few seedlings or even a few hundred seedlings to the acre, but a reproduction which is sufficient to produce a hundred years hence a merchantable stand of timber. Allowing for the natural thinning out of the young growth, there must be at least between fifteen hundred and two thousand seedlings to the acre in order to produce a merchantable stand at the time of maturity. A few hundred seedlings per acre may be capable of growing up and producing a large amount of seed, but cannot produce a merchantable stand of timber." Size and Quality of Timber. — The average diameter breast- high of all timber of merchantable size. If saw timber, the number of sawlogs (16 feet long) per tree and per M. feet board measure. The character, i.e., if unusually clear boled, or limby, etc. Approximate per cent of clear lumber. Condition of Timber. — Soundness, rot or insect attack, etc. These subjects need not be treated exhaustively; the forest description must, above all, be practical and brief. The unit of area in forest description depends, of course, on the degree of intensity possible in the Working Plan. The ideal unit of description is the Stand. The stand is that portion of the forest which is so essentially different in forest type, in method of management, in component species, in age, in density of stocking, or in site, that it is clearly distinct from the sur- rounding forest. The stand as a unit of forest description is ideal, since it is at the same time the true unit of Forest Manage- ment and Forest Organization (see "Division of Area" below). But the necessity of pushing the reconnaissance work and the size of the Working Plan area often makes it more feasible to confine the description to the survey unit — such as the section — or to an entire watershed (in unsurveyed and very mountainous country), leaving it to the Forest Organizer to combine the various descriptions and smooth out their differences and dis- * "Results of Cuttings on Minnesota National Forest," R. Zon, "Pro- ceedings of the Society of American Foresters," Vol. VII., No. I, p. 103. 20 THE THEORY AND PRACTICE OF WORKING PLANS crepancies into a General Forest Description for the Working Plan (see Chap. III). At the same time the Forest Organizer is helpless if these Specific Forest Descriptions are inadequate or inaccurate. Nor need the description contain many words; for mere stereotyped repetition is both tiresome and futile. Division of Area The Division of Area for purposes of Forest Organization is in Europe considered the prerequisite of any Working Plan. For the extensive conditions prevailing in many parts of America the elaborate divisions of area used in Europe can well be waived. Indeed it is conceivable that a useful Working Plan could be constructed without any systematic division of the area. The need for these divisions grows with the refinements in manage- ment, and while it would be mere play in most American forests to mark each compartment and subcompartment in the map or on the ground, a skeleton outline of the salient divisions will often serve to facilitate and to systematize the working of a forest. Unnecessary divisions must be avoided. For these divisions topographic features, roads, trails, etc., should be made the boundaries ; even in flat country the hewing through of compartment lines is justified only under most intensive conditions. The customary subdivisions of a forest are: The working figure (syn. working block, working circle, Betriebsklasse). The block. The compartment. The subcompartment or stand. The Working Figure is that unit which is to be managed with the idea of a sustained yield. It may be only a part of a single administrative unit (e.g., National Forest), or it may comprise several such units. This is discussed in detail in the next section, "Determination of Method of Treatment." THE THEORY AND PRACTICE OF WORKING PLANS 21 The Block is a convenient subdivision of the Working Figure, made to assist in the regulation of the yield. The Block com- prises a logging unit or group of logging units. Since the division of a Block is entirely topographic, a suitable local name can generally be taken from some salient topographic or cultural feature contained therein. The Compartment is a convenient subdivision of the Block, wherever conditions are sufficiently intensive to warrant it. It is created for purposes of easier orientation in the woods and for facilitating and systematizing the keeping of detailed forest records. Where the boundaries of compartments are hewn out or made into roads, these serve the additional purposes of fire lines, logging roads, points of attack in cutting series, and as convenient units where game is beaten from cover.* The "ultima ratio" of division of area is the Stand or Sub- compartment. The distinction is a silvicultural one, i.e., the Stand is that part of the area which through reasons of difference in forest type, in component species, in age, in density of stocking, and in site clearly demands a different method of treatment. It is really, therefore, an independent unit of cutting. It may be large or it may be small; but it must be of sufficient size to warrant the division, and of the right shape — i.e., a long, narrow strip might have sufficient area, but would nevertheless be unsuitable. Minor differences should be disregarded in creating subcompartments— * ' de minimis non curat lex ! " Even under the most intensive European conditions the average minimum size of a Subcompartment is i>< to 2}4 acres. The size of the Sub- compartment is in direct ratio to that of the forest. With decreasing size of the latter one would finally reach the single tree — as is actually the case in the small wood lot managed by the Selection (or Single Tree) System. Conversely, as the forest increases in size and the conditions become more extensive, the subcompartment also increases in area until, for forests of * Hence in the plains, e.g., in the Prussian pineries, the Compartment is called a " Jagen"— i.e., a "Hunting." The average size in Prussia is 25 hec- tares =61^ acres. 22 THE THEORY AND PRACTICE OF WORKING PLANS 100,000 to 1,000,000 acres, the minimum size of the subcom- partment would be about 40 to 160 acres. The degree of difference between two adjacent forest areas necessary to warrant their division into separate stands must be gauged along the following lines: Forest Type. — Differences in forest type always determine differences in stands. Permanent forest types alone are to be regarded in this respect. Component Species. — Minor differences in percentage of mixture or presence of subsidiary species should be disregarded. Only where the component species necessitate a different silvi- cultural method of management or a different rotation, or where there is a marked difference in their market value, should separate stands be recognized. These differences are seldom regarded in young growth — i.e., under one-quarter of the rotation; a mere note in the stand table suffices to indicate the difference and whether the component species are intermingled singly or groupwise. Age is determinative of stand differences especially where the regulation is to be by age classes (Chap. II), and where the forest is essentially even-aged. In the younger growth, i.e., under one-half of the rotation age, differences of 20-35 years can be disregarded; a mere note in the stand table suffices to indicate the difference. Stands over half the rotation age demand a closer classification; not over 20 years difference for the third quarter of the rotation, not over 10 years for the last quarter. Over-mature stands, i.e., over 10 years more than the rotation age, should be segregated as they are the especial objects of an early cutting. In this as in all cases of stand differentiation, the degree of refinement varies with the size of the forest and the intensity of the management. Density of Stocking and Site Quality determine stand differ- ences where they are sufficiently striking to necessitate a dif- ferent method of management (e.g., protection forest on upper slopes). THE THEORY AND PRACTICE OF WORKING PLANS 23 In general it is this Necessity for a Different Method of Manage- ment which is determinative of stand distinction. Where no striking differences in type, species, age, density, or site occur the same method of management applies, and there is no occasion to differentiate into separate stands. Where the methods of management are different the stands are, ipso facto, different. Hence it is impossible within the same subcompartment to have High Forest, Coppice with Standards, and Straight Coppice. Furthermore, even-aged and uneven-aged areas of High Forest are always separated into separate stands. Designation of Divisions. — Working figures and blocks are given names; compartments are numbered; subcompartments (stands) are lettered. E.g., a paper-birch thicket in midst of spruce compartments on the lower slopes of Mount Tecumseh block in the Waterville, N. H., basin, would be designated as 29a, Tecumseh Block, Waterville Figure. Boundaries of Divisions. — Before designating the boundaries of any working-plan divisions, either in the field or on the map, the Forest Organizer, in consultation with the owner and the administrator of the forest, or both, should decide just what divisions are to be made and on what basis. The determination of working figures is a sine qua non, but whether blocks, com- partments, and subcompartments are also to be segregated depends entirely on the specific needs of the forest. Large forests should almost always be divided into blocks. The further subdivision into compartments and subcompartments is necessary only where intensive working plans are practicable. Having decided just how far to go in the matter of divisions, the Forest Organizer keeps this in mind during his preliminary reconnaissance and during the entire progress of the field work. The detail of forest description and the unit described depend on the extent of subdivisions. That is, if blocks are the minimum divisions possible, the organizer needs only the briefest descrip- tions by sections or other survey unit and a mere detailed general description by watersheds or other appropriate logging units, for these are the future blocks. If, on the other hand, the 21 THE THEORY AND PRACTICE OF WORKING PLANS refinements of compartments and subcompartments are possible the unit of description must be the stand, and the forest descrip- tion of each stand must be sufficiently detailed so that the Forest Organizer can determine therefrom whether to make it a sub- compartment, and its function in regulating the yield. Obviously, therefore, the provisional boundaries of the minimum unit of division decided upon must be noted in the progress of the survey and estimate and noted on the map. As the work of gathering the data progresses, the Forest Organizer keeps always in mind the possible division of the forest and, map in hand, goes through the area to determine its most advantageous arrangement. His task will be the easier if the forest description data are well and carefully gathered. Stands (subcompartments) are combined into compart- ments. The boundaries of the former are silvical (see above), of the latter, topographic and natural just as far as possible. Oftentimes the compartment and the stand coincide (which is especially convenient), or a stand stretches partly or wholly over several compartments. Streams, ditches, ridges, landslides, rock barrens, roads, trails, alienated areas, all form natural boundaries for compartments. Only where these natural boun- daries are lacking, or insufficient, is the cutting through of artificial lines permissible. The compartment varies in size from 50 to 250 acres; it is, as far as possible, rectangular or at least trapezoidal in shape, the boundary lines running with or at right angles to the prevailing local storm direction. Where artificial lines are cut through, those running with the prevailing storm direction are called "Haupt-Gestell" (Main Frame) or "Wirtschafts streifen" (Management Stripe), those running at right angles thereto, "Neben-Gestell" (Accessory Frame) or "Schneussen" or "Schneisen" (Glades [sic!]).* The former average 15 to 30 feet in width, the latter 6^2 feet to 15 feet; in this way they serve as a network of logging roads and fire lines. The "Schneisen" * In Prussia the " Hauptgestelle " are 700 to 800 yards apart; the " Neben- gestelle" are 350 to 400 yards apart. THE THEORY AND PRACTICE OF WORKING PLANS 25 serve also to strengthen the stand against windfall; for along them develops the "Waldmantel'' or " Windmantel" — i.e., the crowns of the trees on the border form an impenetrable mantle and protect the interior of the stand from windfall. This is especially important in spruce and similar shallow-rooted species. As the lower branches show signs of dying off, the strip is widened so as to let in the necessary additional light and keep the forest mantle intact, until it reaches a maximum width of 30 or 40 feet. These "Schneisen" are then made the points of attack for the cutting series, since the stand to leeward of them has through its forest mantle ample protection against the storms (Chapter II, Section 2). But, ordinarily, artificial division lines are not necessary. As main lines can be chosen the crests of ridges, the valleys and creeks; as secondary lines the spurs and hogbacks and smaller tributary creeks. Block divisions are always natural and are chosen on a large scale — watersheds, drainage basins, are suitable units. The single block may contain many thousand acres; its shape is immaterial; the governing considerations are logging and mar- ket conditions. The block is essentially a logging unit. Its segregation requires a complete knowledge of such matters as present market conditions, lines of transportation, outlets for the timber, and the probable changes and developments in all three. How far, if at all, the blocks should coincide with the admin- istrative divisions such as ranger districts, must depend on local conditions. It is often convenient to have block and ranger district coincide, and in level country, such as the Prussian pineries, this is entirely feasible. But the purposes of admin- istrative division are so different from those of the Working Plan that the coincidence should never be secured at a sacrifice of either Forest Administration or Forest Organization. The boundaries of blocks and stands (subcompartments) need not be marked on the ground. Compartments must be designated, either by numbered stakes or stones or both, or by 26 THE THEORY AND PRACTICE OF WORKING PLANS stencilling the number of the compartment in white paint on the bark of a tree nearest to the corner thereof. Where the lines are not actually cut through, their intersections with roads, trails, streams, etc., should be similarly designated. Where road or trail or stream itself serves as the boundary, this is not necessary, but merely corner monuments or occasional guide- monuments are placed. On the map the boundary of the Working Figure is marked by heavy dot and dash — . — . — . — ; the blocks by dashes ; the compartments by a dotted line ; and the subcompartment or stand by a thin, unbroken line . Maps and Tables The various data collected in the field should, as far as possible, be entered on maps and summarized in tables. In this way they are made available at a glance. Maps, or, at least, some map of the forest, however crude, are indispensable in Forest Organization. The forest map should contain: (a) Essential topographic features; contours are seldom necessary in level country; hachures are not ordinarily advisable. (b) Roads and trails, railroads, houses, barns, and other "culture." (c) Boundary (exterior) of the forest; also all other interior holdings by other owners. (d) The forest types; also all burns and cut-over areas; all barrens and all land under cultivation or pasturage (non- forest land) within the exterior boundaries. A, b, c, and d may form one base map, or they may be made into separate maps as the wealth of detail necessitates or con- venience dictates. Where the area is too large to be shown com- pletely on one map of ordinary scale (}4 or i inch to the mile), a small scale location map can be made and as many large scale detail maps as are desired. In surveyed country a separate map SKETCH MAP OF PART OF A BLOCK SHOWING THE ARRANGEMENT OF COMPARTMENTS, SUBCOMPARTMENTS, AGE CLASSES AND CUTTING SERIES. LEGEND = BLOCK BOUNDARY 5 = COMPARTMENT NUMBER — = COMPARTMENT BOUNDARY a = SUBCOMPARTMENT LETTER =SUBCOMPARTMENT BOUNDARY *" =PROGRESS OF CUTTING SERIES 35 =AGE OF STAND AGE CLASSES 41-60 III 61"8( IV Fig. 1. 28 THE THEORY AND PRACTICE OF WORKING PLANS of each township, compiled from section sketches, is advis- able. Armed with this base map the Forest Organizer sketches in from survey notes, detail sketches, and forest description the fol- lowing additional points : (e) Provisional division of area into Blocks, Compartments, Subcompartments or Stands, all depending on the divisions previously decided upon. The stands are always irregular in shape and must be combined into compartments of suitable size and shape. Where the forest is approximately even-aged and the method of regulation is to consider age classes, these should be entered on the map by writing the age class of the subcompartment in Roman numerals (see Section i), and coloring or shading it accordingly. Barrens and treeless land are left blank. The blocks are also outlined provisionally. Often the Organizer must go over the area, map in hand, in order to settle some uncertainty on the ground. The boundaries had best be sketched only in pencil. If the original maps are made on tracing linen or on thin bond paper, blue-prints, or, still better, Van Dyke copies can be used for this provisional division of the area. This provisional map quite suffices until the final working- plan document is prepared, when the maps may be elaborated as much as is desired. E.g., the age classes can be shaded or colored, the types colored or symbolized, etc. (see Chapter III). The prevailing local storm direction is entered (where it is not known already it must be determined; in a mountainous region the storms often follow the direction of the main drainage) by means of long dotted arrows (see Fig. i). The next step is to obtain the areas of the various divisions, types, alienations, etc. This is most easily done by means of a planimeter. One decimal place usually suffices. The larger areas are always measured first — e.g., the blocks before the com- partments—the sum of the smaller divisions, e.g., of compart- GENERAL STAND TABLE WO 1 2 3 4 5 6 7 8 9 10 11 12 13 14 DIVISION AREA Compt. (No.) Sub- compt. (ltr.) Total Area Even Aged All Aged Cut Over Burnt I Regulated Unregulated Block (name) Acres Area Average and Age Limits Area m Age Limits Area * Silvi- cult. Method Date and % Left Area Date and % Left Area Date and 1 % * Left Tecumseh I 2 3 4 5 6 7 8 9 IO a b IO4.27 96. 93-73 106. 99.20 103. 97- 99-50 40. 61. 100.30 IO4 96 106 IOO IOO 40 6l 20-40 60-80 I00-I20 140-160 j I-IO 1 I4O-160 I60-200 (160-200) 94 90 80 I-150 I-I50 I-I50 IOO Sh. '02 40% 3 50 1900 clean 1895 10% Culls. 50 1906 None Totals. . . . 1 ,000. 607 264 See Col. 5 53 50 .. * The silvicultural methods J Sh may be designated by the symbols: C = Clear cutting. C str = Clear cutting in strips. C p = Clear cutting in patches ("Well" meth). C ss = Clear cutting with scattered seed trees. = Shelterwood cutting. 5 = Selection cutting. Sh-S =Shelterwood selection cutting. Sh-G = " group Sh-Str = " strip Sh-B = " border " t M.= thousand feet, board measure. [NG FIGURE, AREA... . . .ACRES 16 17 18 19 20 21 22 23 24 25 j 26 27 28 29 STAND DESCRIPTION INCREMENT ductive Stand by Species Curr. Annual Pure, Mixed, Kind of Mix- ture Den- sity of Stock- ing Site Qual- ity Young Growth suffi- cient to Re- stock? Remarks Species Spruce Species Fir Miscellaneous Hardwoods % Rea- Vol. sons M. t Cds. M. Cds. M. Cds. 200 25 P. 1.0 I Yes Thrifty •5 i M. 4OO 35 P. •9 I-II No " •7 2.8 M. 700 30 P. .8 IV Yes " 1. 7M. 9OO 45 P. .8 II No " 1. 9M. Rock 600 300 M. singly •7 IV Yes it 1. 9M. •• I,IOO 75 P. .6 III Half Mature •5 5-5 M. Pasture 60O 300 M. singly .8 III-IV No Grnd. fire •7 6.3 M. 440 60 P. •3 III Half Mature •5 2.5 M. Birch 80 P. 1.0 II-III No Old burns 1. 8 cds. •• 9OO •• P. •5 II-III Yes Decadent; fire scars •3 2.7 M. 100 Aspen 20 M. Grps. .1 II No Bad shape old burn .2 ,2M. 5.840 970 IOO THE THEORY AND PRACTICE OF WORKING PLANS 29 ments, should check with the area of the larger unit (block) containing them. Minor errors can be proportioned. Roads, streams, boundary lines which have been cut through, etc., are seldom calculated as separate areas unless they are excessively wide, e.g., more than 20 feet. Tables are now drawn up to contain these and other data which can be summarized. These may be: (a) Alienation tables (status). (b) Stand tables (volume by species, classes of timber, units of area, etc.). (c) Area tables (by types, by divisions of area). (d) Age-class table (comparison with the normal). Any or all of these tables may be constructed as the data warrant and as there is occasion for them. An alienation table is necessary only where there are many interior holdings, or where the status is complicated. Stand tables are practically a necessity. Area tables are also almost indispensable in a well-regulated working plan. An age-class table is necessary only where the distribu- tion of the age classes plays a part in the regulation of the yield (Chapter II). Tables (6) and (e),to gether with abbreviated notes on site, density, age, and salient silvical characteristics, can be combined into the following General Stand Table. The particular form which this table takes should be varied to meet the needs of the working plan in question. The purpose is to give the essential data for the regulation of the yield; these essential data vary with the method of regulation which is chosen (Chapter II). In the appendix example the table has been made as complete as is necessary even under intensive conditions. The hypothetical data would have required a correspondingly intensive estimate and forest description. The division is by stands. In compartments 1, 2, 3, 4, 7, and 10 the stand and the compartment coincide; compartments 6 and 8 are one stand; compartment 9 has two stands or sub- compartments. These data will be required for only those forests which permit of an intensive management. However, the same form 30 THE THEORY AND PRACTICE OF WORKING PLANS of table, with minor modifications, applies to even the most extensive conditions. For example: If the estimate and description is by survey units, e.g., by sections, quarter-sections, or even forties (reconnaissance), the arrangement of the columns would be varied so that Col. 2 would be township and section, Col. 3 the quarter-section or forty, Cols. 5, 7, 9, n, 13, and 15 would give the area, not in acres, but in per cent of total, Cols. 6, 8, 10, 12, 14, and 16 would usually indicate the age only as Over-mature (0), Mature (if), or Young (F) (see Section 2, above). Cols. 23-29 would usually be recorded separately for each type. If the estimate and description are lumped for the entire area of one type within the same watershed, Col. 2 would be the name of the type, Col. 3 would be blank, Cols. 5 to 22 inclusive would be as in the paragraph above, Cols. 23 and 26 would be very general, Cols. 24 and 25 would fall away, but Cols. 28 and 29 would be retained. From the above data, a rough age-class table can, and, for all methods of regulating yield by the distribution of the age classes (Chapter II), should be constructed. Assuming in the hypothetical data of the general stand table above that the rotation is 160 years, the form of age-class table would then be as follows: Age Class Table A. In the above example if only the symbols "0," "M," and "F" are used, the comparison would be: Age Class Table B. Were the intermediate steps O/M and Y/M used also to designate the approximate age of the stands, the table would read: Age Class Table C. THE THEORY AND PRACTICE OF WORKING PLANS 31 71 Id pj U < • i W V) (/) 1 3 u Os "3 2 • 2 rt . ° <-> a • M o so * "5 SO I . so 00 M X + M • so • 01 M > o . . . o . o . . . . . . . . o . ■* . . . O <* r>. . tsj 00 • M oo >o .-I •-I > o lO lO 00 00 00 00 SO o oo * t~~- 00 M O M > o o 0> > o o CO 00 00 00 00 SO OS in w> od * r>. oo CO > o 00 M o O ID lO oo 00 00 ■+ i> B o ■■o (0 B CN o r>. . csj 00 * lO 00 M o lO « o CN o SO lO lO 00 00 oo cq op 3 "* CD u < O O o — . en !qJ5 1 O £ ■4-> £ o c S «» •s -s i b 2 rt §*"£ u O • — bo U Q < tJ- s£> so On tO N O* O h O O On Os O On O o o •+ ^ o MM'-' M a t c 1 4-> ft 6 o CO 14 -1 ri j3 ; 4J ft E o O OJ MCNCO^^NOt^oOON O A! (J o 5 I-t u E JB ' 3 * u H 32 THE THEORY AND PRACTICE OF WORKING PLANS 4J (U tn ffl-— > u. rt S3 ."So oj2 mPQ to ! o : tO o V Pi « H tn j It o " PQ rt o 1 O io in CO to CO CO «< J O tn O vO >0 ov n- io oo 0) to a) |H tn 3^ a> 3 + ; - H o go a) a) " M ■ M >^ VO " VO O «■ 01 >-. o nJ O o o_ t— 1 — < m tal, «rma ficit rplui c 2 5 C H C 3 3 2 ^J HI ■2 S I- ; u rr ■* • ij rt vO \0 o w CS C* Ph tn *tfl m 0) E.M •- - 3 a o *2 IS ni ; rt— « fc« vo vo 1 o» o JH <*> 3 m 0) JS-g - rt . to • to o ; o rt M l-l tn M aj . m2 o o Th oo ■* • >H vo r>. m l-t M . ^^ H J ^ PQ o 00 tn 4) "aT < o 1- ; ; U >H »D M- CO 1 to r^ t CO !5 M M <1 h3 O 'o tn • jj^ H H " ^ rt o o 00 rt < vo oo r a) cd J • 6. u o vO tn . -4-1 0) . c o L- ^ I ts^-. U • J3 (U H Cfl • as o r^ t- ,. • 1) tS * Td- t^- t : iE | M M 6 tn + • - o u *o 03 — ' w . t-H O VO . . VO tn 500 + 3,S«x»,°°°-io,7iS,°°° = 6o200 feet bm (3) 36,785 + 3.5o°,ooo - ,,574,950 _ ^ ^ [^ With Judeich's suggested modification, the value of Karl's formula is as a rough method in irregular stands or as a check upon other methods of regulating the yield. For this purpose either it or the just suggested modification of the Austrian formula may be used according as the current or the mean annual increment has been determined. 7. BY VOLUME.— BASED ON GROWING STOCK AND INCREMENT. HUNDESHAGEN'S METHOD. (a) Description of Method.— Hundeshagen conceives of the increment or yield as the interest on the growing stock and assumes that the actual yield is to the actual growing stock as the y ny normal yield is to the normal growing stock, or: — = — ny transposed this is y = v — which is the Hundeshagen formula. nv ny Hundeshagen calls the factor — the "use percent" ("Nutz- nv ungs prozent"). If nv is calculated by means of the mean annual / ri\ . . . . . ny 2 increment nv = — and ny is taken as = 1, then — ■ = — . Hun- \ 2 / nv r deshagen, however, calculates nv by means of yield tables (see method for even-aged stands under No. 5). ^ is the volume actually present in the forest. Hundeshagen suggests a short-cut method wherein for cal- culating nv and v only those stands are to be considered whose r age exceeds - and thereby a "partial use per cent" obtained. (b) Example. — An uneven-aged forest of Western yellow pine contains 3,500,000 feet board measure of timber 12 inches and over diameter breast high, on 1,000 acres. The mean annual increment (i) is assumed at .7 per cent, the rotation at 200 60 THE THEORY AND PRACTICE OF WORKING PLANS years. Disregarding Hundeshagen's method of determining nv by ny 2 2 means of yield tables and taking — = - = — = .01, the for- J nv r 200 mula gives: y = v— = flX.oi = 3, 500,000 X.oi =35,000 feet board measure tVu equals annual cut. This result is identical with that obtained by Von Mantel's formula (No. 4) or by the Austrian formula (No. 5) modified (as suggested under No. 6) by making the period of distribution of excess or deficit equal half the rotation, e.g.: v — nv y = 1 + 2 ri but nv = — 2 (ri\ / 24,500X200^ hence y = z + v — \ — )= 24,500+ 3,500,000— ^— —J r 200 2 2 = 24,500 + 10,500 = 35,000 feet board measure equals annual cut. (c) Value and Application. — This method, published by Hundeshagen in 182 1, was really discovered by Paulsen in 1795, though Hundeshagen never knew of the latter's work until 1830. It presents no advantages over the methods already described and some very substantial disadvantages : (1) The assumption that the actual yield is to the actual growing stock as the normal yield is to the normal growing stock is not always correct, especially not where there are over- mature and deteriorating stands in the forest. (2) The value of v changes constantly, hence, to be strictly accurate, y would have to be redetermined annually. (3) The method provides no definite period for the distribu- tion of surplus or saving of deficit in the growing stock. A THE THEORY AND PRACTICE OF WORKING PLANS 61 cutting plan is permissible, but does not affect the volume of the cut as determined by the formula. Hence under the method, overmature stands can be dragged through many years if the growing stock is excessive or immature stands cut off though the growing stock is already deficient. The only real use of the formula in irregular, uneven-aged stands is as a check on other methods. Its use in even-aged stands presupposes normal yield tables and regulated conditions, neither of which exist in America at present nor will exist for some time to come. 8. BY VOLUME.— BASED ON GROWING STOCK AND INCREMENT. BREYMANN'S METHOD. (a) Description of Method.— Based on Hundeshagen's for- mula, Breymann assumed that the actual yield is to the normal yield as the actual average age is to the normal average age of a stand. Hence y = ny — (a = age). Now ny = ni (mean annual increment) and na = — . The average age can be determined either by area according to the formula: a = — - t — —7 — * wherein f h / 2 , f 3 , etc., equal the area of the J 1 +72+73 various age classes and a h a*, a 3 , etc., equal their respective aver- age age (see examples under " Distribution of the Age Classes, " Chapter I, Section i, and under "The Latent Rotation," Chapter I, Section 3, "Rotation") or else the average age can be deter- mined by volume according to the formula: v l + v 2 + V* a = -: ; -• wherein v l , v 2 , v*. etc., equal the volumes of the — I -\ 5 H r. a 1 a" a various age or diameter classes and a 1 , a 2 , a 3 , etc., their respective age (see example under "Distribution of the Age Classes," Chapter I, Section i). (b) Example. — A forest of Western yellow pine containing 3,500,000 feet board measure of timber 12 inches and over 62 THE THEORY AND PRACTICE OF WORKING PLANS diameter breast high, on 1,000 acres, is essentially uneven-aged, but shows three distinct diameter classes: 12 to 18 inches, average 14 inches ("Black Jacks"), and 20 inches and over, average 26 inches ("yellow pine"). The volume of the former is 20 per cent of the total, or 700,000 feet board measure; the volume of the latter is 80 per cent of the total, or 2,800,000 feet board measure. The average age of a 14-inch "Black Jack" is 70.5 years, of a 26-inch "yellow pine" 285 years.* Then by the formula, v l + v 2 700,000 + 2,800,000 3,500,000 = -T 2 -^ = — J o — = — , Q Q = 176 years. v v 700,000 2,800,000 10,000 + 9,818 a 1 + ~a 2 70 + 285 The adopted rotation is, however, only 200 years, hence Y 200 na = - = — = 100. The current mean annual increment is 2 2 placed at 0.7 per cent, or 24,500 feet board measure. By the formula y = ny — = 24,500 ( — J =24,500 X 1.76 = 43, 120 feet board measure, equals annual cut. (c) Value and Application. — This method, promulgated by Breymann in 1854, aims in common with the other "formula methods" to secure an approach of the actual growing stock toward the normal growing stock. However, in addition to the employment of data which are difficult and subject to error in irregular stands and extensive conditions (e.g., normal incre- ment and average age calculations), it has the strong drawback that the adjustment of the excess or deficit in the growing stock is spread over the whole rotation, whereas the exigencies of the occasion usually warrant this adjustment in a fraction of that time. The method is, therefore, of little practical value except as a check upon other methods of regulating the yield. *From Table 9, Bulletin 101, Forest Service, U. S. Dept. of Agric. THE THEORY AND PRACTICE OF WORKING PLANS 63 9. BY VOLUME.— BASED ON GROWING STOCK AND INCREMENT. HEYER'S METHOD. (a) Description of Method. — Heyer bases his formula on the following premises: (1) If a stand is normal, then an amount equal to the mean annual increment can be cut each year so long as the three requisites of normality are maintained, i.e., (a) normal growing stock, (b) normal increment, and (c) normal distribution of the age classes (see Chapter I, Section i, "The Normal Forest and Its Attributes"). (2) If normality in (a) and (b) exists, but (c) is abnormal, it can be made normal if the normal increment is cut annually or periodically, and the cut-over stands immediately regen- erated. (3) If the actual increment is less than the normal increment (the contrary can scarcely ever occur), then, even if the growing stock is normal, only the actual, not the normal, increment can be cut. (4) If the growing stock is abnormal it can be brought toward normality by either cutting less than the actual increment if the growing stock is too small, or cutting more if it is too large. (5) The period of distribution (x) of excess or deficit, i.e , the time during which an abnormal stand is to approach normal- ity, can be determined only with regard to local exigencies, it must be developed out of a general plan of management which is in consonance with the wishes of the owner. If v < nv then x must equal at least a period of years sufficient so that the sum of the actual increments during that period equal the difference between v and nv; where this is exactly the case then y (the annual cut) equals o. On these premises Heyer develops the formula: v + ix — nv y = x ; i is the actual mean annual increment, and hence really varies from year to year. Hence as i improves, the approach toward normality is accelerated to less than x years, as it grows 64 THE THEORY AND PRACTICE OF WORKING PLANS smaller the approach toward normality is retarded to more than x years. This variation of i Heyer meets by calculating i not solely according to its present condition, but by conceiving of the expression i x as the increment during the period of x years, with regard to all the probable changes in increment during the x years. This is facilitated by the drawing up of a plan of cutting (distribution of yield) as outlined in Section 2 of the present chapter. nv is found by the formula — in which Heyer takes i as the normal mean annual increment, but at the same time raises the question whether taking i as the actual mean annual would not be equally correct.* (It has now come to be universally considered as the correct method.) (b) Example. — An uneven-aged forest of Western yellow pine contains 3,500,000 feet board measure of timber 12 inches and over diameter breast high, on 1,000 acres. The mean annual increment equals .7 per cent, equals 24,500 feet board measure. The rotation is taken at 200 years. The normal growing stock . ri 200 X 24500 . ... equals — = = 2,450,000 feet, v is, therefore, > nv by 1,050,000 feet. This excess is, in view of local exigencies and T 200 the wishes of the owner, to be distributed over — years = = 50 4 4 years =x. By the formula: v + ix — nv __ 3,500,000 + (24,500,50) — 2,450,000 y ~ x 50 3,500,000 + 1,225,000 - 2,450,000 = = 45, 500 feet board measure equals annual cut, which is exactly the same result secured by the Austrian formula (No. 5) modified as suggested under 6, , s . . , v — nv , 3,500,000—2,450,000 (c),t.e.,y = * + —-- = 24,500+^^ ^ =45,5oo x 50 * Judeich, " Forsteinrichtung " in Lorey's "Handbuch der Forstwissen- schaft," 2d edition, Vol. III., p. 425, foot-note. THE THEORY AND PRACTICE OF WORKING PLANS 65 feet board measure. The only difference is if i x is modified to correspond with expected changes during the next x years — as outlined above. (c) Value and Application. — -Carl Heyer's formula dates from 1 84 1, and is perhaps the only one of the formula methods in active use to-day, having been adopted by the grand duchy of Baden for the determination of the volume yield; this is supplemented by a careful cutting plan (Distribution of Yield) for the next period of years (see Part Two, Chapter I). Gustav Heyer, in the revised edition of Carl Heyer's work,* adds a complete period distribution of the yield similar to that described under No. 17 below. However, this is possible only under regular conditions and in even-aged stands, and in no way destroys the effectiveness of Heyer's formula in irregular uneven-aged stands, although it correctly emphasizes the importance of adding to the mere volume determination of the yield a "when" and "where" by means of a careful cutting plan (distribu- tion of yield) as described below in Section 2 of the present chapter. With this in mind, Heyer's formula is directly applicable to the majority of American forests, especially to those where, as in virgin forests, the actual growing stock is far in excess of the normal growing stock and a reduction to normal is of prime importance. Summary and Comparison op the "Formula Methods" The "formula methods," or, more properly, the "growing stock methods" ("vorratsmethoden"), for there are other methods employing formulae to determine the yield, all aim to have the actual growing stock approach the normal. This is secured by a purely mathematical ratio of increment and growing stock, whereas, oftentimes, the character of the stands and other * Carl Heyer, "Die Waldertrags-Regelung," 1841. Second and third editions edited by Gustav Heyer, 1862 and 1883. 5 66 THE THEORY AND PRACTICE OF WORKING PLANS conditions of management which do not admit of mathematical expression are of more importance. In combination with a careful cutting plan (distribution of yield) the Heyer formula serves as a useful determinator in irregular, uneven-aged forests. It is better than the other formulae for the reasons already detailed under (c) "Value and Application," although the other formulae will serve as a useful check. The superiority of the Heyer formula is still further evident when the results of the examples based on identical premises are compared: y (annual cut) in feet board measure Current No. Method If nv = ri 2 If nv = r' i* 2 Including young growth, etc. S. Austrian Formula 29,750 55,300 56,000 35,ooo 43,120 45,5oo 35,ooo 42,350 70,000 70,700 60,200 41,410 6. Karl's Formula 65,086 li — ni\ 65,786 \ a i 7. Hundeshagen Formula 8. Breymann's Formula 9. Heyer's Formula 55,286 For Comparison: 3. Methode de Masson ) 10. BY VOLUME.— BASED ON DIAMETER CLASSES. METHODE DE 1883 (" FRENCH METHOD »).f (a) Description of Method. — Instead of constructing a stand table, the total volume of each diameter class should be determined. Some figures should also be obtained showing the number of trees of the diameter desired at the end of the rotation (exploitable diameter) which there would be per acre in a nor- mally stocked stand, if no other age classes were present. Since * See explanation under No. 5: (a) "Description of Method" and (b) "Example" of Austrian formula. t Adapted from Barrington Moore's article " Methods of Regulating the Cut on National Forests," in Vol. VII., No. 1, " Proceedings of the Society of American Foresters." THE THEORY AND PRACTICE OF WORKING PLANS 67 these figures must be taken in the field, sometimes before the exploitable diameter has been decided upon, several diameters should be taken. When the desired exploitable diameter has been decided upon, determine f^om the growth figures the number of years necessary to produce this diameter. This number of years, lengthened by a few years to allow for a possible delay in reproduction, will be the rotation. Divide the trees shown by the estimates into three groups as follows : ist group, old trees. Those containing two- thirds of the exploitable diameter and above; e.g., if the exploitable diameter is 30", this group would contain trees between 20" and 30". 2d group, medium trees. Trees having a diameter falling between one-third and two-thirds of the exploitable diameter; e.g., trees between 10" and 20". 3d group, young trees. Everything with a diameter less than one-third of the exploitable diameter. The calculation of the yield is based on groups 1 and 2, and is made in the following manner: Find the volume of each of the first two groups. Then if the volume of the old trees is to that of the medium trees as 5 is to 3 the proportion of the two groups may be considered normal.* If the proportion is normal it will be possible to cut the group of old trees, plus their increment, during the first third of the rotation, the increment, of course, being figured for only half of the third of the rotation. But, first of all, it is necessary to ascertain whether or not the volume as a whole is too great or too small. This is done by finding the total volume which there would be if half of the * This ratio is based on the relative age of the old group and the medium group; it will vary with the length of the rotation, the conditions of growth, and the species. In the present instance, if the rotation age is 150, each group covers 50 years, i.e., the old group 100-150, average 125; the medium group 50-100, average 75. Then the old group is to the medium group as 125 : 75 = 5 =3- 68 THE THEORY AND PRACTICE OF WORKING PLANS entire area were covered with trees of just exploitable size* (not of very large mature trees). In obtaining this volume the num- ber of exploitable trees per acre, called for above, is used. The result should be approximately equal to the sum of the old and medium trees. If the result is less the forest contains a surplus; if more, it contains a deficit. There are five distinct possibilities : (i) The volume of the old and volume of the medium trees may be in the proportion of 5 13, and sum of their volumes normal. In this case nothing further is necessary before the actual calculation of the cut. (2) The volume of old and medium trees may be in the pro- portion of 5 13, but their sum less than normal. In this case it will be necessary to increase the growing stock. This can be done by cutting, during the first third of the rotation, only the old trees, without their increment, or, if the area is very badly understocked, by cutting less than the old trees. (3) The volume of old and medium trees may not be in the proportion of 5 13, and their sum nevertheless normal. This is adjusted by transfers from the group which is too large to that which is too small. (4) The volume of old and medium trees may not be in the proportion of 5 13, and their sum less than normal. This will probably mean that the volume of old trees is deficient, and must be increased by cutting less than the otherwise allowable volume of old trees. (5) The volume of old and medium trees may not be in the proportion of 5 : 3, and their sum more than normal. This could occur only with an excess in the old group. To correct this, find the volume of old trees necessary to make the ratio 5 : 3 with the volume of the medium trees, and which, added to the volume of medium trees, will give a normal growing stock. The difference between this volume and the actual volume of old trees is surplus. This surplus must generally * In dealing with open stands, such as Western yellow pine in the South- west, the area must be considered as fully stocked with exploitable trees, but due allowance must be made for natural openings and bare places. THE THEORY AND PRACTICE OF WORKING PLANS 69 be removed during the first third of the rotation, for the entire area will be cut over once during that time. Even though it were desirable to distribute this surplus over a longer period, such a course would generally be impossible, because in virgin forests, most of them of difficult accessibility, the first cut must be heavy per acre to justify logging. Later cuttings may, with- out hardship to purchasers, be made lighter. When several species occur in mixture all are regulated together without affecting the method. If one species has a more rapid growth and is shorter lived, requiring a shorter rotation, its exploitable diameter should be made lower than that of the other species. The whole calculation is checked by figuring what per cent of the total volume is represented by the allowable cut. This per cent, after subtracting the surplus, should be approximately the growth per cent of the group of old trees. The area check on this method is applied as follows: The whole working circle (working figure) is to be gone over in one-third of the rotation. Since the rotation may be long, this third is further divided into periods during which the plan is to run without revision. If these periods are too short an unnecessary expense will be incurred by frequent reconnaissance work, whereas if they are too long there is danger that the effects of original errors may accumulate. A period of about 20 years seems reasonable. Thus if the rotation is 180 years, the whole working circle will be cut over in 60 years. If the period during which the plan is to run be 20 years, the area is divided on the basis of topography into three parts, each containing about an equal volume, and each to be cut over in 20 years. In some cases, where the working circle does not lend itself to a division into parts containing equal volumes, it may be divided into unequal parts, each part to be cut over in a period bearing the same relation to the one-third of the rotation as the part bears the whole working circle. The part containing the largest proportion of overmature and deteriorating timber should be cut during the first period. This part may be further subdivided 70 THE THEORY AND PRACTICE OF WORKING PLANS for convenience into watersheds forming natural logging units or groups of units (blocks). (b) Example. — Total area of working circle = 200,000 acres. Minimum merchantable D. B. H. = 10". Size of material desired: Sugar pine and yellow pine = 30". Incense cedar = 24". The group of old trees will include those 20" and over D. B. H. The medium trees will include those between 10" and 20" D. B. H. The average length of time required to produce a tree 30" D. B. H., considering the important species, is 160 years. The period of reproduction is approximately 20 years. Hence the rotation will be 160 +20, or 180 years. Incense cedar is shorter lived and more rapid growing, hence will be considered exploit- able at 24" * Table of Estimates Medium Trees Old Trees Volume M. Feet Volume M. Feet Sugar pine Yel- low pine Incense cedar Total D. B. H. inches Sugar pine Yel- low pine Incense cedar Total Volume of Volume of IO Volume of Volume of sugar pine and yellow incense ce- dar for each II 12 sugar pine and yellow incense ce- dar for each pine for diameter 13 pine for diameter each diam- class up to etc. each diam- class 16" eter class up to 19", inclusive. 15", inclu- eter class 20" and over. and over. 200,000 1 ,800,000 * This exploitable diameter for incense cedar will cause a slight inac- curacy in that the medium trees should be taken to 8" instead of 10" to correspond with the 24". On the other hand, the volume between 8" and 10" will be small, and if desired can be allowed for by sample tallies over a small percentage of the strips. The cutting of a short-lived species to a lower diameter limit is desirable in this case because the area is gone over only once in 60 years. THE THEORY AND PRACTICE OF WORKING PLAKS 71 From the table we find the actual proportion of old and me- dium trees to be: Old trees = 1,800,000 M. feet Medium trees = 200,000 M. feet Total, 2,000,000 M. feet The normal proportion should be: Old trees, 2,000,000X1 = 1,250,000 Medium trees, 2,ooo,oooXf = 750,000 But the normal growing stock over the whole area, considering half of the area stocked with 30" trees, should be 1,120,000 M. This should be divided between the two groups as follows: Old trees, 1,1 20,oooXf= 700,000 M. Medium trees, i,i20,oooX|= 420,000 M. 1,120,000 M. Hence, although there is a surplus of 1,800,000 — 700,000 = 1,100,000 M. feet of old trees, there is a deficit of 420,000 — 200,000 = 220,000 M. in the medium trees. If all the old trees were cut during the first third of the rotation the growing stock would be depleted. Therefore 220,000 M. feet will be taken from the lower diameters of the large trees, chiefly from the more valuable species, and added to the medium trees. The resulting surplus will be 1,100,000 — 220,000 = 880,000 M. This surplus is to be removed during the first third of the rotation. The cut for the first third of the rotation will therefore be the 880,000 M. surplus and the 700,000 M. normal volume of old trees, plus the increment on their sum. This increment will be 12,000 M. per annum, or 12,000X30 = 360,000 for the 60-year period.* Therefore the annual cut for the first third of the rotation will be: 800,000 + 700,000 + 360,000 Y = — = 32,333 M. feet. This amounts to 1.61 per cent of the total volume. Not counting the surplus or increment on the surplus, there will be * The increment is taken for only half of the period because cutting is • going on. 72 THE THEORY AND PRACTICE OF WORKING PLANS a cut of only 853,000 M. feet for the 60-year period, or an annual cut of only 14,216 M. feet. This is but .71 per cent of the total volume, or approximately the increment on the group of old trees. In carrying out this method, site qualities producing very marked differences in growth must be distinguished in the field work and kept separate in the computations. For instance, in some of the very dry limestone soils of the Western yellow-pine belt of the Southwest the trees are small and stunted, and even when mature hardly reach the diameter of poles on ordinary sites. Such areas if small and unimportant may be thrown out and ignored; but if of some extent they should generally receive a separate calculation of yield and proper consideration in the final allotment of the cut. (c) Value and Application. — A disadvantage of the French system is that it requires the tallying of trees down to one- third of exploitable diameter. This means that if the ex- ploitable diameter is 24" everything above 8" must be tallied. It is, therefore, best adapted to a high diameter limit and long rotations, which is, however, generally the case in many of our selection forests. The advantages of the method are elasticity and a degree of accuracy not attainable with formulae. 11. BY VOLUME.— BASED ON DIAMETER CLASSES. INDIAN METHOD.* (a) Description of Method. — This method is based on the principle that a certain number of trees reach a size suitable for cutting every year or period of years. The aim of the method is to cut just this number of trees. The data required are: 1. A careful enumeration of the growing stock. For this purpose five or six broad classes are made fr >m seedlings up to mature trees. * Adapted from Barrington Moore's article, "Methods of Regulating the Cut on National Forests," in Vol. VII., No. I, "Proceedings of the Society of American Foresters." THE THEORY AND PRACTICE OF WORKING PLANS 73 2. Growth figures, particularly showing the number of years required to pass through each class. 3. Figures showing the percentage of mortality suffered by each class as it passes into the next class above and into the final or mature class. The rotation is generally the sum of the number of years required to pass through each age class till the exploitable size is reached, with generally a few years added on to make it con- servative. The felling period is a convenient subdivision of the rotation and should be at least the length of time required to produce enough material to justify the next cut. The annual cut is calculated in the following manner: The number of trees in each class is multiplied by the percentage which will survive till maturity. The results are added and then divided by the rotation plus one-half of the felling period.* In order to find the growing stock of Class I trees the average annual yield as found above is multiplied by half of the felling period. In order to allow for mortality this number is raised by multiplying by / Mortality per cent \ . The growing stock thus found is compared with the actual growing stock to find whether there is a surplus or deficit. The annual cut is allotted accordingly, distributing this surplus or deficit over a certain period according to the proportion of lower classes and reproduction. The area check is applied by prescribing the order of the fellings through the different subdivisions (compartments) of the working circle. A table is drawn up showing for each year the subdivision on which the cut is to be located and number of trees to be removed. * Half of the felling period is added to the rotation to allow for the num- ber of Class I trees (the largest class) which should always be on the ground, because there should always be a number of Class I trees equal to the Felling period . , 2 X average annual yield. 74 THE THEORY AND PRACTICE OF WORKING PLANS (b) Example. — Total Growing Stock Class Species I 28" and over D.B.H. 11 24" to 28" III 18" to 24" IV 12" to 18" V 6" to 12" VI Below 6" D.B.H. Yellow pine .... 13,178 11,366 19,770 42,577 117,590 215,667 Rotation = 150 years Felling period = 15 years From a table showing per cent of each class, reaching Class I, and the per cent of Class I surviving 15 years, the following calculation is made: Average annual yield = (13178 X .95) + (11366 X .83) + (19770 X.66) + (42577 X 150 + ¥ .50) + (117590 X .30) + (215667 X .10) 150 + ¥ 12519 + 9472 + 13180 + 21288 + 35277 + 21567 157-5 157-5 719 trees per annum. The growing stock of Class I trees, which there should always be, is therefore 719 X V 5 - X 1.025 = 5532. Since there are 13,178 Class I trees, a surplus of 13,178 — 5,532 = 7,646 trees exists. The cut for the period over which it is desired to distribute the surplus will be: The present Class I trees, plus the total number of trees reaching Class I in the period, minus the growing stock, all divided by the period. A modification may be made by calculating the annual yield on the basis of only the upper classes (the first three or four) instead of on all classes. The sum of these classes is then divided by the number of years which the lowest class used will take to become Class I instead of by the rotation. (c) Value and Application. — Practically the only place THE THEORY AND PRACTICE OF WORKING PLANS 75 where the single tree method is used is in India. There it is used almost to the exclusion of all other methods. It is par- ticularly well adapted to mixed tropical forests in which only one or two of the many species found is merchantable. The disadvantages of the method are its lack of elasticity, its complexity, and liability to error; it also requires as many data as better methods. Hence it should be used only in excep- tional cases. 12. BY VOLUME.— BASED ON DIAMETER CLASSES. DIAMETER- CLASS method:(hufnagl). (a) Description of Method. — I, yield in volume only; II,. yield in volume and in number of trees. I. For uneven-aged (selection) forests the yield can be deter- r mined if all stands or trees more than — vears old are known and 2 • their increment. This presupposes the fixation of the rotation age (Chapter I, Section 3, "Rotation"). By means of ring- counts on stumps of average diameter it is then determined r at what diameter breast high the trees have an age equal to-. All trees of this diameter and over are next estimated — prefer- ably in three-inch diameter classes — and their volume and current annual increment determined (see Chapter I, Sections 1 and 2). r Y then equals volume of trees or of diameter classes - years and over, plus increment thereof in — years; this sum divided by 4 r -. (For underlying theory see Formula Methods above.) II. Going a step further, diameter can be substituted for age. After determining at what diameter, and upwards, the trees are most merchantable, it follows that all trees of this diameter and larger are merchantable and should, other things being equal, be cut in the near future, i.e., during a period of years required 76 THE THEORY AND PRACTICE OF WORKING PLANS for the next lowest diameter class or classes to produce an equal number of merchantable stems. But since the lower diameter classes contain more trees than the higher classes, therefore more than replacing those cut in the higher class, proportionately more of the oldest stems can be cut. To express this numerically, the period of years separating the diameter classes must be known, i.e., the average age of the average tree in each diameter class. Let this value equal a h (h, a 3 , etc. The volume of the average tree in each diameter class must also be known (volume tables, measurement of repre- sentative trees, etc.). Let this value equal v h v 2 , vz, etc. Let, finally, the number of trees in each diameter class equal n x , n 2 , n 3 , etc., and the formula follows: T , n 4 , n 3 — n 4 . n 2 — n 3 . th — th Y = — Vi + v 3 + v 2 + Vi #4 — #3 di — a S # 3 — #2 (h — #1 Hufnagl further advocates the comparison of y obtained by this method with y obtained by current annual increment (method No. 4 above) and, if necessary, the use of only the first one or first two of this series of expressions so as to make the results correspond, and also periodic revisions of the data on which the method is based. Since the method is particularly intended for selection forests it is Hufnagl's theory that the cutting cycle shall equal approx- imately di — ds years, i.e., the time required for the highest non- merchantable diameter class to become merchantable. (b) Example. — A certain uneven-aged forest of Western yellow pine is to be managed on a 200-year rotation. Stump y analyses show that at the age of - = 100 years the average diam- eter breast high equals 18 inches.* The estimate of all trees over 18 inches diameter breast high equals 1,085,200 feet board measure, divided as shown below. The current annual incre- ment is assumed at .7 per cent. * Adapted from Bulletin 101, Forest Service, U. S. Dept. of Agric. THE THEORY AND PRACTICE OF WORKING PLANS 77 (1,085.200+ /7,596X200V J = 14,650 feet board 2 measure = annuai cut. Substituting diameter for age (variation II) and assuming the diameter classes to be as follows*: D. B. H. Average Volume Intervening Years inches feet b. m. No. of Trees Total Volume (from diameter growth tables) IO-I2 60 240 14,400 13-15 no 440 48,400 16-18 190 770 146,300 I9-2I 3IO 720 223,200 22-24 480 (w.) 580 {iii) 278,400 45 (a 2 — «i) 25-27 710 (i> 2 ) 410 (n 2 ) 291,100 47 (a 3 -a 2 ) 28-30 1,020(2/3) 190 (w 3 ) -93,800 48 (a 4 —a 3 ) 31-33 1,410 (» 4 ) 70 (« 4 ) 8,700 Now, having determined that the trees are most merchant- able at a diameter of 22 inches and upward, it follows that the last four diameter classes are ripe for cutting. Applying the formula : w 4 70 . ■ , Y = v 4 = -- X 1410 = 2,059 f eet o- m - CLi — #3 4° , n 3 — m 190 — 70 . J - H v s = — - — ^- L - X 1020 = 2,550 feet b. m. Gi — a 3 48 ih-fh 410 - 190 , H v-, = X 710 = 5,204 leet b. m. 4 di — CLz H v 3 = 2,059 + 2,550 = 4,609 feet b. m. #4 — #3 The cutting cycle equals a 4 — 03 = 48 years, or, roughly, 50 years. (c) Value and Application. — This method, first published by Hufnagl in 1893,* * s excellently adapted, especially in its second variation, to the irregular and over-mature selection forest which is so commonly encountered in all parts of America. It is especially well suited to virgin stands, tending to cut the excess growing stock (of overmature timber) within the first cutting cycle, and yet providing ample material for a second cut at the end thereof (in 50 years from first cut). The data which are required are those of every thorough reconnaissance preliminary to a working plan, namely, data on diameter-class distribution, on number of trees in each (in repre- sentative stands), of volume, and of diameter growth or, in the first variation, of increment (current annual) . If it is not feasible to tally diameter classes for the tract, carefully chosen, fully stocked sample plots of varying site classes will suffice, but when applied to the total stand must be reduced to correspond with the varying density of stocking. When accompanied by a plan of cutting (distribution of yield) for the next decade, the method is perhaps the most practical yet invented for irregular selection forests. Indeed, it is intended for just such conditions in the more remote parts of Austria. 13. BY AREA AND VOLUME.— FOR ENTIRE FOREST. RUSSIAN METHOD. (a) Description of Method.f — This method is primarily adapted to forests managed under the shelterwood or shelter- * " Oesterreichische Vierteljahrschrift fur Forstwesen," 1893, pp. 177 and following. f From a translation by Mr. Raphael Zon of the Forest Service. THE THEORY AND PRACTICE OF WORKING PLANS 79 wood-selection system (see Chapter I, Section 3) wherein the timber is cut off gradually and regeneration stretches over a period of years known as the "regenerative period." The method is described as follows: "The area is taken for the measure of the annual cut, al- though it is generally admitted that in such forests the area is less appropriate measure than in forests with clear cutting. In selection forests there cannot be any annual cutting area, but an area which is to be cut over during the number of years which is contained in the regenerative period, since during that period the entire forest area must be cut off. Instead of an annual cutting area in selection forests there must be taken a periodic area, the size of which is obtained by dividing the area of the forest by the quotient resulting from division of the rotation by the regenerative period. In order to obtain an equal annual cut each year it is necessary to determine the amount of standing timber on the periodic area which is to be cut over and then aim to cut annually only an equal part of that amount. Of course this tendency to cut every year an equal amount of the standing timber may be disturbed at the time of a good seed year, when it will be desirable to cut over a larger area, and cut less during the years when there is no seed. Since, however, the regenerative period is always of some length, it will always be possible to equalize to some extent the amount to be cut within that period. On a large area which is being cut over within a given regenerative period it is possible to increase during poor seed years, the so-called preliminary cut- tings, which allow more light into the stand, while in good seed years such cuttings may be suspended and stress laid chiefly upon so-called regenerative cuttings, which secure natural reproduction. If the area which is being cut over consists of several different types containing different species, the chances are that the seed years will not occur in all the species at the same time. This again may help to equalize the cut- tings from year to year. Finally, even if it is impossible to equalize the amount of timber to be cut every year, this 80 THE THEORY AND PRACTICE OF WORKING PLANS drawback will be more than offset by the advantages of this method. "Properly speaking, not only the entire stand over the area which is to be cut over within the regenerative period should be taken into account in determining the annual cut, but also the increment that will take place within the regenerative period. This, however, is a very complicated undertaking, and it is best to determine the annual cut within the regenerative period merely on the basis of the actual standing timber, leaving the future revisions of the working plan to take account of the increment." (b) Example. — A thousand-acre forest of Western yellow pine, containing 3,500,000 feet board measure, is to be man- aged by the shelterwood-selection system with a regenerative period of approximately 50 years. The rotation is set at 200 years. 1,000 The periodic cutting area = =250 acres. The cutting plan (distribution of yield) shows that the 250 acres selected 3,500,000 for cutting in the next 50 years contain not = 875,000 4 feet board measure, but, since this part of the stand is somewhat 1 .000,000 overmature, 1,000,000 feet board measure. ythen= — = 50 20,000 feet board measure = the annual cut for the next 50-year cutting period. (c) Value and Application. — This method is exceedingly simple and applicable only under very rough conditions, as is shown by the fact that it dodges all calculations of increment. It has the advantage of simplicity and the disadvantage of being too ironclad. It is, however, a primitive recognition of the important interrelation of volume and area in the determination of the yield. THE THEORY AND PRACTICE OF WORKING PLANS 81 14. BY AREA AND VOLUME.— BASED ON AGE CLASSES. DIRECT METHOD (HUFNAGL*). (a) Description of Method. — If the volume and the area of "the oldest stands which, presumably, will be cut in the next ten or twenty years, is known, the average volume per acre v equals -. This volume multiplied by the allowed annual cut in area equals the allowed annual cut in volume. (b) Example. — Referring to example of method No. 1 above: Variation I. Area not reduced. Annual cutting area equals 62.5 acres. The volume of the oldest stands to be cut in the next twenty years (oldest age class) equals 1,000,000 feet board measure, their area is 250 acres. v Then the average volume per acre = - = 4,000 feet board measure. The volume of the annual 0^ = 4,000X62.5 = 250,000 feet board measure. Variation II. Area Reduced. Using the figures given in the example of Variation II, Method No. 1 above: Annual cutting area reduced to terms of Site Quality I equals 6.64 acres. The stands ripe for cutting in the next twenty years (oldest age class) show an average stocking of .7 and an average site quality III, and hence (from yield tables or from measurements of sample plots of mature fully stocked stands of varying site qualities) an average volume of 68,000 X. 7 =47,600 feet board measure per acre. 6.64 acres of site quality I are to be cut per annum. This is equivalent (see example, method No. 1, Var. II) to 10 acres of site quality III. Hence the annual cut =47,600X10 = 476,000 feet board measure. Variation III. Hufnagl. Using the figures in the example under method No. 1, and the example under Variation I of the present method: * Hufnagl, "Praktische Forsteinrichtung," is the source of this and the subsequent method (No. 15). 6 82 THE THEORY AND PRACTICE OF WORKING PLANS V The average volume per acre = - = 4,000 feet board measure. The volume of the annual cut = 4,000X29 = 116,000 feet board measure. (c) Value and Application. — As noted under similar heading in method No. 1 , the method has all the disadvantages of a fixed value for the rotation, instead of a naturally adjustable one, and allows none of the free play so necessary for the best silvi- culture. Variations I and III are exceedingly simple, and hence quite well adapted to forests with fairly uniform conditions, i.e., coppice and coppice with standards. Variation II is too com- plex for all but the most intensive conditions, and requires all the data, while possessing none of the advantages of other and better methods. Obviously the method presupposes an age- class table, and hence a forest composed of fairly even-aged stands. It is therefore essentially not a method for selection forests. Furthermore, it is applicable only to forests wherein the oldest age class does not average more than r +5 years, i.e., is not more than 5 years older than the rotation. This condition is seldom attainable in American high forest, and for high forests, aside from its occasional use to check other figures, the method therefore lapses into merely historical interest and as the basis of the stand method (No. 16) and the various period methods (No. 17) discussed below. 15. BY AREA AND VOLUME.— BASED ON AGE CLASSES. HUF- NAGL'S METHOD. (a) Description of Method. — Hufnagl's premise is that the sustained yield can be determined directly if the volume and the Y increment of the stands now more than — years old is known. This method presupposes a stand table containing the volume Y and area of all stands of over — -years. To this volume is to be r added, also, the increment of these stands in the next — years; THE THEORY AND PRACTICE OF WORKING PLANS 83 for since the area of these stands diminishes each year, and in Y the year — = 0, the increment can only apply, on an average, to half the area. As to the increment, Hufnagl distinguishes two variations of his method according as I the current, or II the mean annual increment is used. r I. The current annual increment of each stand over - 3'ears old having been determined (by yield tables or by field measurements, Chapter I, Section 1), the sum of these incre- ments is used in the formula which follows. V II. The mean annual increment equals— . It can be deter- mined from yield tables or, empirically, by measuring average stocked stands of average site quality whose age approximates V r years. — then equals the mean annual increment. HufnagPs formula then follows : (letting V equal the volume y of stands - years and over, A their area, i the increment in board feet per acre per annum, current or mean) : v + a .i .r r- i r 2 If i equals mean annual increment it will usually be 10-20 per cent less than the current annual increment. This makes its use the more conservative of the two. (b) Example. — In a forest of 2,160 acres with a rotation of 80 years, the stands 40 years and older have a volume of 3,21 1,000 feet board measure on 1,120 acres. The mean annual incre- 2 211 OOO ment for the rth (80th) year equals — '■ X .007 = 2,867 X 84 THE THEORY AND PRACTICE OF WORKING PLANS .007 = 20.069 = 20 feet board measure. Then by the formula: — v + a . i . r _ 4 _ 3,211,000 + (1,120 X 20) 20 r_ 40 2 3,211,000 + 4 48,000 = 91,475 feet board measure = annual cut. (c) Value and Application. — Hufnagl's method shows much originality and is applicable to even-aged stands of only mod- erate regularity, the very conditions encountered in many American forests. Its age-class differentiation is very simple, as is also the volume and increment determination. The latter had best be the mean annual increment, and can readily be calculated from sample plots if yield tables are lacking. A disadvantage of the method is the rigid fixation of the rotation age, which should really be a flexible quantity; but if this is offset by frequent revisions at regular intervals the method will pass muster, especially in the irregular stands common to most parts of America. If this method of calculating the yield is adopted, it must always be supplemented by a careful cutting plan (distribution of yield) (see Section 2). 16. BY AREA AND VOLUME— BASED ON AGE CLASSES. THE STAND METHOD (JUDEICH'S "BESTANDSWIRT- SCHAFT »)• (a) Description of Method. — Judeich* bases his method on the undoubted fact that no method of determining the yield for a period of years in advance — some even attempting to do so for the whole rotation or a substantial part thereof — is accurate without frequent revisions which recognize the unexpected changes inevitable in every stand no matter how carefully managed. He therefore makes no attempt to regulate the yield for more than a decade in advance, but prescribes not only a revision, but a new plan at the end of the decade. * Adapted from Lorey, "Handbuch der Forstwissenschaft," 2d edit., Vol. III. THE THEORY AND PRACTICE OF WORKING PLANS 85 In order to secure a sustained yield the annual cut is cal- culated with the following three regulating factors: (a) The normal yearly cutting area or volume; (b) The distribution of the age classes; (c) The results of previous cuttings. The more the results of previous cuttings, especially with regard to their effect on the distribution of the age classes, are available, the greater is the justification in regulating the yield for only a decade in advance. Where there has been no previous working plan nor adequate record keeping (with especial respect to volume, area, and distribution of age classes) the yield must be determined two, three, or at most four decades in advance. Judeich does not give any certain method of ascertaining the yield — either in volume or in area — but adapts this to the peculiar exigencies of each forest. The object of the working plan is the attainment of normality in the distribution of the age classes; this is secured by a correct cutting series (see Sec- tion 2) and cutting policy. The cutting policy selects for the next decade or two, or r at most, three or four, all the stands or groups of stands which require cutting for one or more of the following reasons: 1 . Administrative necessity. 2. Disease and decadence (overmaturity) . 3. Maturity. 4. Inferiority, slow growth. The sum of stands ready to cut for reasons 1-4 gives in area and volume the cut for the next period, subject to the following regulating factors: (a) The normal yearly cutting area or volume. (b) The distribution of the age classes. (c) The results of previous cuttings. (a) Can be determined by any of the methods already described, by area if the distribution of the age classes is not too abnormal (e.g., method No. 1), by volume, preferably, if the distribution of the age classes is far from normal and there is a preponderance of overmature timber (e.g., method No. 9). 86 THE THEORY AND PRACTICE OF WORKING PLANS Judeich expressly states that his method is not restricted to a financial rotation, but is equally well adapted to rotations on other bases (see Chapter I, Section 3, " Rotations"), e.g., that of greatest volume or of technical production. (b) Example. — Assuming a general stand table such as that given in Chapter I, Section 2, from this it appears that the follow- ing stands* are in need of cutting during the next ten years: Compt. Subcompt. Area Stand Reason No. Letter acres Species and M. ft. b.m. 1. Administrative necessity .... .... .... .... 2. Disease and decadence. .9 b 61 Spruce 900 .... 10 .... 50 Fir 100 3. Maturity 6 .... 100 " 1,100 " 75 8 .... 40 " 440 " 60 Total 251 Spruce 2,440 Fir 235 = 2,675 M. feet. The distribution of the age classes (see age class table, Chap- ter I, Section 2) shows a considerable abnormality, as follows: Overmature Mature Young Restockable (160 + ) (81-160) (1-80) blanks. Actual acres 61 266 300 103 Normal " . . 355 355 Deficit " .. 89 55 Surplus " 61 ... ... 103 The rotation is 160 years; the total area 710 acres exclusive of natural blanks, and the protective belt of all-aged forest (see foot-note) . Despite the abnormality, the annual cutting area is here calculated for the sake of an example, e.g., by method No. 1, . . T , ^ A 710 variation I, the annual cutting area = — = — - =4.43215 acres. For ten years = 44.3 125 acres. The cutting for the next ten years would, therefore, be con- fined entirely to compartment 9b. But if variation II were to be used (assuming the same * The all-aged selection forest of the protective belt is necessarily omitted since it obviously requires a different method of computing the yield. THE THEORY AND PRACTICE OF WORKING PLANS 87 values as in the example under method i, Variation II) the reduced area would be, reduced to terms of site I: 104 acres, Site I = 104 acres X 1 00 = 104 acres. 96 it " I/II = 96 ' ' X 92= 88 a 106 tt " II = 106 ' 1 X 83= 88 tt 103 tt " III = 103 ' X 66= 68 it 100 tt " III = 100 ' ' X 66= 66 tt IOI it " II/III = 101 ' ' X 75= 76 a IOO tt " II = 100 ' ' X 83= 83 it 710 => nnr n a 1 ri lttincr arpa reduce d area 573 _ 573 _ ■} rS 160 for rotation ten years equals 35.8125 of Site I or equivalent. The 61 acres in 9 b are Site II/III. It requires 1.35 acres of Site II/III to equal one acre of Site I. Hence 35.8125X1.35=48.35 acres of per- missible cutting area in 9 b during the next ten years. The volume can then be determined by multiplying the average stand per acre for the site determined from yield tables or from local measurement by the per cent of stocking and then by the reduced acreage (see example under Variation II, method No. 14). But where stands are so irregular in age classes, site quality, and density of stocking, it is not well to resort to area as the regulating factor, but rather some volume method, such as Heyer's, of comparison with the normal growing stock (method No. 9). This would give : i (increment) = 5,840 M. feet of spruce X (say) .007 =40,880 ft. b.m. 970 M. feet of fir X .01= 9, 700 ft. b.m. Total, 50,580 feet. r =160 ri nv = — =4,046,400 feet b. m. v = 6,810,000 feet b. m. v > nvby 2,763,600 feet b. m. 88 THE THEORY AND PRACTICE OF WORKING PLANS Let x (the period of distribution) = - = — ■ = 40 years. Then by the formula : v + i . x — nv 6,810,000 + (50,580 X 40) — 4,046,400 x 40 119,670 feet board measure. The annual cut therefore equals 119,670 feet board measure. The cut for the decade equals 1,196,700 feet board measure. There is within compartments 9 b, 10, and part of 6 and 8 ample (2,675 M. feet) for the cutting within the next decade. Compartments 6 and 8 need scarcely be touched, which is just as well, since they are barely mature now. If, however, in view of the proportionately large amount of mature and overmature timber it is desired to reduce the period of distributing the surplus to ten years, the result would be: 6,810,000 + (50,580 X jo) — 4,046,400 Icj — = 326,940. The annual cut therefore equals 326,940 feet board measure. The cut for the decade equals 3,269,400 feet board measure. There are within compartments 9, 10, 6, and 8 only 2,675,000 feet, hence the management must either be conservative and content itself therewith or add compartment 4, with 945,000 feet to the cutting areas for the decade, which would make 3,620,000 feet board measure, or ample whereon to draw for the 3,269,400 feet board measure to be cut. (c) Value and Application. — This method is without doubt the most rational of all the methods of determining the yield; for it attempts no iron-clad rule or framework — such as the "period methods" next to be considered — but depends entirely on the silvicultural and economical requirements of the forest. By means of frequent revisions the amount cut can never endanger the continuity of the forest's productiveness, while it allows full play to the skill of the officer in charge of the manage- ment of the forest. The forest moves steadily toward a normal distribution of the age classes, but this very desirable goal is attained without undue sacrifices. THE THEORY AND PRACTICE OF WORKING PLANS 89 It is a method of great freedom and adaptability. Freedom in so far as the cutting of certain stands is not prescribed far in advance for a certain time, but entirely according to the exi- gencies of the situation. It is adaptable to all methods of high forest which result in even-aged or fairly even-aged stands, i.e., to all but the selection system. The method in its simple application is well suited to Amer- ican conditions where it is often of prime importance to dispose of the overmature and decadent timber within the reasonable check of a sustained volume yield aided by the corrections of decennial redetermination of the yield and striving toward the distant goal of a normal age-class distribution. 17. BY AREA AND VOLUME.— BASED ON PERIODS (" FACH- WERKSMETHODEN " *). (a) Description of Method.— The rotation is divided into a number of equally long periods of time. Usually these periods comprise twenty years. Every stand or subcompartment is assigned to a period corresponding with its age, so that each part of the entire area of the working figure, with the exception of certain areas reserved for selection forest, protective belt, or other special purpose, is used once during the rotation. The sums of the individual periods must be approximately equal, or somewhat higher for the later periods. If this is not the case, adjustment is necessary, by transferring certain stands or subcompartments to an adjacent period. According as this adjustment emphasizes equality of area, or equality of volume, or equality in both, different kinds of period methods are recog- nized as: I. Area-period method (" Flachenfachwerk ") ; II. Volume-period method (" Massenf achwerk ") ; III. Area-and- volume-period method (" Kombiniertes Fachwerk"). I. In the area-period method ("Flachenfachwerk") the areas are assigned to various periods either as actual areas or as *The name " Fachwerksmethoden " comes from the German "Facher" or pigeon-holes into which the various parts of the forest are placed by these methods. A "Facherwerk" or "Fachwerk" is, therefore, a framework con- sisting of many pigeon-holes, and these methods are "Framework" methods. 90 THE THEORY AND PRACTICE OF WORKING PLANS reduced areas (see method No. i above) of equal productivity. The method aims to cut each year, or each period, an equally productive area containing an approximately equal volume. The age-class table is the basis of the assignment to periods, however these must then be shifted to secure equality of utiliza- tion in each period. Knowing the area to be cut in the first (immediate) period and (from yield tables or empirical measure- ments) the volume yield thereof, the annual cut is found by dividing this volume by the number of years in the period. This volume calculation is usually confined to the first period. Final cuttings are restricted to this period. 1 20 In a rotation of 1 20 years there are, e.g., = 6 periods. Were the age-class distribution normal, the periods and the age limits of the stands comprised therein would be as follows: I Period Age of Stands 100-120 years II III IV V VI 80-100 60- 80 40- 60 20- 40 o- 20 In practice this method is restricted to simple, regular con- ditions with artificial regeneration after clear cutting. The area "framework" has the advantage of simplicity and ease of application. Within the rotation, if no unforeseen disturb- ances occur, the normal age-class distribution is attained. But the method has the great disadvantage that no due regard is paid to existing conditions (age-class distribution, growing stock, increment). In the case of an overmature, broken stand more should be cut than a strict period method permits; in the case of immature stands, less should be cut than this period method provides. Equality of periods is secured, often, only at a tre- mendous sacrifice. II. In the volume-period method (" Massenf achwerk ") the aim is to have an equal yield in each period. The various periods are, therefore, given approximately equal volumes, although the younger periods are sometimes endowed with slightly higher THE THEORY AND PRACTICE OF WORKING PLANS 91 volumes ("Massen") than the older periods. The annual cut is found by dividing the volume of the first period by the number of years therein (usually twenty). The individual stands (compartments and subcompartments are not requisite in this method, nor even the formation of work- ing circles) are assigned to the periods corresponding to their age. Their volume is then prorated by means of yield tables or, at least, increment tables so as to determine the volume they will have at the time of reaching the middle of the I period {i.e., the cutting period). These volumes are then compared and the necessary adjustments made; the stands are shifted from one period to another, e.g., if the II period were deficient, the IV period excessive, some stands would have to be shifted from the IV into the III period, and from this into the II period, until the proper balance was secured. Since this "shifting" carries with it a recalculation of the final yield because of changed increment, the method involves an enormous amount of cal- culation. This method was founded by G. L. Hartig in 1795. It finds no application in practice to-day. It has the advantage over the area "framework" of cutting an equal volume each year, and hence more nearly approaches the desires and needs of timber owner and timber buyer. But it has the glaring disadvantage of attempting to regulate the cut for a whole rotation. The future treatment of stands must depend on eventualities which cannot be foreseen in the present. Nor can the method be used in the extensive, irregular conditions for which it is intended because of the lack of adequate volume and increment data. Furthermore, an equal annual cut may dis- regard overmature stands in need (financial and silvicultural) of cutting, or, conversely, cut stands which are not yet mature. It is an unnecessarily narrow concept of sustained yield; it does not even secure normality, for (Chapter I, Section 1) volume, i.e., growing stock, alone is no criterion of nonnality. III. The area-and- volume period method (" Kombinierte Fachwerk") aims to combine the area "framework" and the 92 THE THEORY AND PRACTICE OF WORKING PLANS volume "framework" so that each period will contain approx- imately equal areas and volumes. Theoretically this distribution of volumes is for the whole rotation and is achieved for the I period by means of valuation surveys, for the other periods by means of yield tables. Areas and volumes are then adjusted as in the area "framework" and the volume "framework." The annual cut is then obtained by dividing the area and the volume of the I period by the number of years contained therein (usually twenty) and letting the two factors of area and volume act as a mutual check.* In practice the difficulty of predicting volumes for a whole rotation and of equalizing volumes and areas, led to an im- portant modification whereby the volumes are calculated for only the I period or > at most, the I and II periods; the areas, however, delineated, roughly, for the whole rotation so as to insure a sustained yield. This method was founded by Heinrich Cotta in 1804. The important modification of restricting the volumes to the I or I and II periods dates from von Klipstein in 1823 and von Grebe in 1867. With this modification the method is to-day used in Prussia, Hesse, Wurttemberg, and in Austria (see Part Two, Chapter I). This method possesses the combined advantages of the area and the volume "framework"; it secures a greater regularity of volume yield than does the former and a quicker approach toward normality than does the latter. Combined with a proper distribution of the age classes and a liberal interpretation of equality in the periods, the method secures good results. But with too strict construction it results in crass errors, such as the needless leaving of overmature stands simply because they * A number of variations have been suggested, e.g., annual cut = volume of period -J- years of period (Prussian practice); annual cut = area of period -4- years of period (Auhagen); annual cut = area of (I or I and II) periods -f- years and reduced to volume (von Stockhausen and von Grebe). In practice both factors are regarded ocal conditions demand. THE THEORY AND PRACTICE OF WORKING PLANS 93 are in the sacrosanct II period and can't be touched,* or the cutting of immature stands which were placed in the I period merely to "fill in." (b) Example. — Since, from what has gone before and what follows (c) these methods are so obviously unsuited to American conditions, it would serve no useful purpose to elaborate them by examples.f (c) Value and Application. — In most of the German States the "framework" methods were the foundation of regulated management and thus exerted a mighty influence on German forestry. But under the conditions of modern times they have steadily diminished in importance for the following reasons : (i) The silvicultural method of management, to which the method of regulating the yield must conform, is often in direct disagreement with the "framework" method. The latter demands that the cutting on a given parcel (e.g., compartment) be completed within the period (twenty years). This is often impossible without silvicultural mistakes and economic sacri- fices. The natural regeneration of many species requires more than an arbitrary period of, say, twenty years. Even with artificial reproduction there are often unavoidable and unfore- seeable events which make complete regeneration impossible within the period. (2) The concept of sustained yield which endows each period with an equal area or volume, or both, is unnecessarily narrow. For practical purposes it suffices that the area or volume, or both, of the next working period be in reasonable ratio to the total area or volume, or both, of the entire working circle. Modern economic conditions have greatly changed the concept of sustained yield (see Chapter I, Section 3). Present economic conditions often demand the cutting of other than the exact * This has led to the growing demand for the "Opening of the II Period." t These may be found in Judeich's or Martin's "Forsteinrichtung" (see Bibliography) or in Lorey's "Handbuch der Forstwissenschaft," 2d ed., Vol. III., pp. 411, 415, and 423. 94 THE THEORY AND PRACTICE OF WORKING PLANS period area; the zone of economic influence has extended tremendously. (3) Cutting series (see Section 2 of present chapter) are not dependent on a period method; indeed the latter often resulted in cutting series of excessive length. (4) The assignment of every compartment or other parcel of the forest to a certain period presumes a certainty of judgment on the part of the Forest Organizer amounting to prescience. As a result the cumbersome calculations are often valueless. (5) These calculations of yield for the whole rotation in advance are the more unnecessary since, under proper admin- istration, there are frequent revisions of the working plan at regular intervals. Taking all these together, it is a just criticism of the "frame- work" methods to say that they are too hide-bound, adapted only to even-aged stands, to intensive conditions, and to methods of clear cutting with artificial regeneration. The realization of this has brought about a revulsion away from these methods. Most of the German States have definitely abandoned the rt framework"; in others it still persists, but without any weight ©n the determination of yield for future periods (see Part Two, Chapter I). Review of the Methods of Determining the Yield No single one of the methods described above will be adapted to all varieties of conditions. The choice of method depends: 1, on the intensity of management possible; 2, the kind of forest, arid 3, the silvicultural system adopted. In the light of these considerations, the methods may be valued as follows: Method No. 1 is chiefly adapted to coppice and coppice with standards. Methods Nos. 2 and 3 for provisional determination of the yield under rough conditions, and as a check on other methods. Method No. 4 as a check on other methods. Methods Nos. 5-9 (" formula methods ") : Of these all but THE THEORY AND PRACTICE OF WORKING PLANS 95 No. 9 are restricted to rough calculations in irregular stands and as checks on other methods. No. 9 (Heyer's formula) finds a wide application in uneven-aged, virgin stands when supple- mented with a careful cutting plan. Method No. 10 is adapted to high diameter limits and long rotations. Method No. n is adapted to mixed tropical forests where only one or two of the many species are merchantable. Method No. 12 is excellently suited for irregular and over- mature selection forests. Method No. 13 is restricted to very crude conditions. Method No. 14, variations I and III, for coppice and coppice with standards. Method No. 15, for even-aged stands of only moderate regularity. Method No. 16, the ultima ratio of fairly regular, even- aged stands. Method No. 17, not adapted to American conditions. It is always advisable to calculate the annual yield by a variety of methods so as to have a check on the figures. It will often be the case that a crude working figure will contain both even-aged and uneven-aged stands. The yierd must then be calculated separately for each and, when the plan is revised, the time may be ripe to make each of the two kinds of forest into a distinct working figure. For the determination of yield the process should be as follows: First determine the allowed annual cut, in volume or in area, by means of one or several of the methods described. Then choose the cutting areas according to silvicultural and economic necessities. To do this requires a careful cutting plan — or plan of distribution of the yield — which is next to be con- sidered. 96 THE THEORY AND PRACTICE OF WORKING PLANS SECTION TWO DISTRIBUTION OF YIELD To make the actual annual cut conform directly to the determined yield, i.e., to cut yearly the exact amount specified in the working plan, is neither possible nor desirable. Unfore- seen contingencies, both silviculturrl and economic, often necessitate an overcut one year, ai undercut the following. If the working plan must be flexible ^ven under European con- ditions which allow the forester to decide the "where" and "when" of cutting, how much more is it necessary in America, where the "where" depends on profitable accessibility and the "when" on market conditions. It therefore suffices entirely to keep within the allowed cut for the working period of ten or twenty years — the time before the next revision of the working plan — and to make no attempt to cut one-tenth or one-twentieth thereof each year. In other words: a periodic sustained yield rather than an annual sus- tained yield should be the aim. For similar reasons, a great flexibility must be allowed in the selection of the actual cutting areas. The working plan properly lists certain areas to be cut within the working period of ten or twenty years — the time before the next revision of the working plan — but these cannot be rigidly adhered to, cannot in Europe, and much less so in America. European experience has brought about a great liberality in this regard — the executive officer in charge of the forest is given freedom of choice as to what areas he wishes to cut each year of the working period,* this yearly cutting plan is viseed and approved by his superior officers, otherwise he has carte blanche to exercise his judgment. No other course is possible in America, where conditions are far * With due regard, of course, to supplying local needs for timber and to a proper distribution of classes of timber so as to keep values from fluctuating and to provide industries dependent on the forests with the timber they need. THE THEORY AND PRACTICE OF WORKING PLANS 97 more extensive. The working plan designates certain areas, certain cutting series even; beyond this it cannot go. It must help and not hamper the managing officer. It is merely a frame within which he exercises his individual ingenuity. Selection of Stands to be Cut The conditions which govern the selection of stands to be cut are: market, maturity, damage (insects, fungi, etc.), wind- fall, fire, and the like. Under market are contained all the manifold considerations of logging accessibility, of profit in cutting and marketing, and the sizes and species which can be logged. For example, a spruce stand on top of an isolated mountain like Mt. Graham in Arizona may be fully mature and in need of cutting, but unless there are adequate logging devices which can market the timber at a reasonable profit, it is useless to designate this as the sole cutting area of the next working period. Similarly, there may be large amounts of fir (abies) in mixture with other species such as spruce and Douglas fir, but unless the fir is accepted as lumber and as ties it cannot be counted on the same basis with the other species. Finally, where material below a certain diameter cannot be marketed at a profit it should not be considered a part of the cut of the next working period. In other words, the cutting plan must deal first with actualities confronting the administrative officer and put hypothetical utilization in a subordinate place. Other things being equal, the cutting plan provides for the logging of all mature and overmature stands, i.e., such as have attained or passed the rotation age. If the forest is even-aged or fairly so, these stands are those of the highest age class or classes. Stands which show damage by insects, fungi, etc., should usually be cut; they are therefore included in the cutting plan for the next working period. Stands which have suffered severe windfall must often be 98 THE THEORY AND PRACTICE OF WORKING PLANS cut speedily so as to prevent further damage.* But, further than this, the lessons of past windfall must be applied in dis- tributing the yield — e.g., to remove a certain stand may expose the one behind it and subject it to almost certain windfall. This can best be regulated by the formation of cutting series, described below. The windfall danger varies, of course, with species and character of stand, with soil and site, and with the prevailing wind direction. Spruce is exceedingly subject to windfall and often requires especial precautions. Stands damaged by fire enough to necessitate regeneration, but not enough to be rendered unmerchantable, must be dis- posed of speedily before further deterioration. Mapping op Stands to be Cut The type and stand map of the forest is of the greatest value in deciding on the areas to be included in the cutting plan for the working period, especially when supplemented by complete and reliable forest descriptions of each unit. Referring to the map given above under Chapter I, Section 2, "Maps and Tables," and presuming that it is possible to log and market where, when, and what one wishes, but that the windfall danger is great, making many "points of attack" preferable to extensive, con- secutive cutting areas, the following stands would be chosen: 4a, 7e, and 8a can be cut without in the least endangering any other stands. 6e, however, though it is sixty-five years old, cannot be cut before the larger, but only sixty-year-old 6a, because this would immediately subject 6a to heavy windfalls. Hence 6e must wait until 6a is cut. This involves a balancing of whether it is the more desirable to cut 6a and 6e now or to wait until 6a is fully mature. Other things being equal, 6e must wait, since it is the smaller. The stands or blocks in which it is intended to cut during * In the spruce stands of the Black Forest, Germany, it is not uncommon to have the entire annual cut taken up by unexpected windfalls. THE THEORY AND PRACTICE OF WORKING PLANS 99 the coming working period should be indicated on the working map either by color, or shading, or symbol. The kind of cutting intended, e.g., shelterwood, can also be indicated by using the symbols given in the "General Stand Table," Chapter I, Sec- tion 2, above. Cutting Series When one cutting area is purposely joined to another and this to a third, etc., they form a cutting series. Cutting series always progress from some initial "point of attack" against the pre- vailing wind direction. They are shown on the map by arrows. The formation of cutting series is a tremendous safeguard against windfall, especially where at the point of attack a forest mantle has formed on the edge of the stand to leeward. This mantle consists of the persisting middle and lower branches of the trees on the edge of the stand. It is artificially stimulated during the youth of the stand by the cutting through of com- partment lines or "Schneisen" (see Chapter I, Section 2, "Boun- daries of Divisions"), or forms naturally along a road, stream, or other topographic interruption. It can also be created by heavy thinning along the edge of a stand or compartment whereby the crowns remain deep and hence the trees windfirm. Cutting series can seldom be arranged without some minor sacrifices. For example, in the map the small, forty-eight-year old stand 7d lies in the midst of the nearly merchantable seventy- two-year old stand 7e: 7d would be sacrificed to the cutting series, the lesser good to the greater. Only if the borders of 7d were liberated so as to form a mantle, could it be left after 7e has been cut. This would be done in the case of 7g, since it is a much younger stand. Cutting series must be decided upon by the Forest Organizer during the progress of the field work in order to gauge the sac- rifices properly. They can be provisionally entered on the working map by using dotted arrows. Theoretically the cutting series are like steps, actually they 100 THE THEORY AND PRACTICE OF WORKING PLANS are always somewhat irregular even under favorable conditions. In the map, 5d and h, and 5e, f, g, and i obviously belong to two cutting series. But 5I is a separate proposition because it must be cut before 5I1 since it is more than twice as old (5h = 23 years, 51 = 52 years). Cutting series must be planned decades in advance, and require careful thought and accurate judgment. The cutting of such a series may require many years; early mistakes are difficult to correct. Cutting series are necessary only in even-aged stands of shallow-rooted species, but there they are of tremendous im- portance.* Their regular adoption in America is still of the future, but the principle can be utilized now. Plan of Cutting Having determined "how much" and "where" to cut during the ensuing working period, this is reduced to a documentary plan of cutting or "felling budget." Two kinds of cutting plans should usually be drawn up: I, a general one for the entire working period — i.e., for the num- ber of years to elapse before the next revision of the working plan, generally ten years; and II, a specific plan for the ensuing year. I. The general cutting plan provides cutting areas sufficient to yield (if the working period is ten years) at least ten times the volume of the allowed annual cut or ten times the area, as the case may be. It should, however, provide for some- what more, so as to provide additional cutting areas in case of unforeseen contingencies making the cutting of certain areas impractical or allowing a higher cut than was originally intended. Under fairly regular conditions the cutting plan may cover the next twenty years, or even forty years, but under average Amer- * By this means windfall is checked and controlled in the spruce forests of Saxony; the lack of cutting series is largely accountable for the tremendous •windfall in the spruce stands of the Black Forest in Baden. THE THEORY AND PRACTICE OF WORKING PLANS 101 o M o 55 o 55 <: H H u W W o (U p 13 c 01 (L) C 00 u J2 0) t Ih J3 "H. bo _E 3 o ft CD 3* « a c3 Ih 3 01 JO O o tN o Os c -^ aj a cd u o > o Si Ih 3 > o E 41 a E U +-> 3 O O S Pi "c3 "*" c o lO O o Os OS o <*■ 00 l^ o Os >-i o H S* lO 00 ID HH W H to o •a 6? H 73 W — u S Bj a 1 Q ir> o o . z &5 00 t^ o < 14 t-H i H 1 P 6h o UO o o »o . a n S 00 3 in ft 01 o o o o S rh VO VO M3 ■* ■* o ; g 8 H o O o H <1 RJ v£> to O o 1-1 M ro • -2 o o o o c o o vO \o tn -UN l-i ^ M bo 4 h o to §.S .d 4J 3 o - -' ^ GO o5 OS o vo 00 _o u < ■C J3 -c -C ^ CO o S en 0) en "en s S E E ■2 5 3 3 3 3 m s u O (J O 0) o 0) 0) H H h H o a5 3 U o 2 +3 -a u +-> *H en o 0) T3 C C O 3 O co U +H E .E x '0 V a a o e <3 03 u )-■ o as a >> H i a 3 4- C E- THE THEORY AND PRACTICE OF WORKING PLANS 131 J3 H s M « 3 O •a J3 o § i O w «i X '3 W a a o c3 > H c o "-3 o o "3 -> o H 132 THE THEORY AND PRACTICE OF WORKING PLANS ft H < On i-l Ph * 1> f) T3 £ 03 H > u > 3 Q "re 4- c THE THEORY AND PRACTICE OF WORKING PLANS 133 SECTION FOUR CONTROL AND REVISION OF WORKING PLAN No working plan can remain alive and useful unless it is revised at frequent, regular intervals. These revisions incor- porate all the changes which have taken place during the working period. Since the working period is usually ten years, the working- plan document is usually revised every decade. But under very intensive conditions more frequent revision may be justified, even to the extent of every five years (see Example of Saxony, Part Two, Chapter I). On the other hand, a plan should not, ordinarily, go without revision for more than a decade, or per- haps twelve years, even though the working period be longer, e.g., two decades, or even four, as in Prussia and Austria, respect- ively (see Part Two, Chapter I). Especially under the kaleidoscopically changing conditions in most parts of America is it desirable to have frequent revisions so that the working plan may really "work" and not become obsolete within the working period. Special revisions before the end of the working period are, of course, necessitated whenever, through storm, purchase, or the like, a substantial change is caused in the size, character, or composition of the forest. The record of the progress of the forest under the working plan is called the control book. This book is conveniently in two parts: I, the cutting and planting record; II, the general or " history" book. The former may conveniently take the following form (page 134). It is obvious that this part I of the control book is built up from the annual cutting and planting plans. It embodies their essentials in convenient form as a permanent record. It can, of course, be extended to cover all the activities of the forest besides "timber," e.g., grazing. A column for areas can also be added between columns 3 and 4 if desired. 134 THE THEORY AND PRACTICE OF WORKING PLANS P o M O M o PM o O PQ o O Q Id H Z < m cd' O u w ft 1-1 o v k? o CO OJ rH ° y l> o ft* J p rH 1 O H O) >< 0) H P o 0) i-l 00 "3 3 CJ I> CO .J. <" to tS w 1-. cti 1) <* 5 a) 8E CO is u « o s iH CO 3 o 'u be O 3 3. 11 -3 4-> .3 3 * E o /-\ 3 • "o . 3 TJ s O u en a) in -~ .3.3 S o •§ ° § S3 -§ O Q m S +-* Jft « t> * J * < CJ u-i CJ a «^SlilS- o u u C u rt 3 en +J .4JC/1 = *0 3 cu g"rt ^ O +J 1?, ft CU tO y .3 3 O ft 3 E ■— +J 3 s -O 3 +-> en cu en ~ 3 3-2 g >* a, s OX o> cu r< cu < *-i 1) «r 8 g o ^ *« w 3 h i- 3 &0J co en v S > 3 3 u £ d)f£ be^ +j *i>? T i-3 g en o-5- ^.E: « 3^ d » t, "u 3 OJJD C ,3X! H< < O C^ u be 3 CN ^-r 3 bOTj 3 3 t! tn 3- a _ o S ft 3 ^» O 4J' +J- CU E en cS •tJ s 3 3^ u ft >. en 0) 0) b ^ tn o sJ J2 en cj 3 ^Tl Xi 3 3 o^ en 0) 3 3 3 E ^ £ £ ft JJ b/0 cu e enC^ 3 > ft u M fi ^ 4-1 h J2 r\ C 4-> S^ 3 a aj O c3 CD aT 3 ^ en -r? oj LJ iS 3 cu .• ^ 3 en " o s y 3 ^3 3 d 3 i OJ co J-J CU THE THEORY AND PRACTICE OF WORKING PLANS 135 A separate page is kept for each convenient unit — be it block or compartment, township or section, depending on the needs of the administration. All areas cut or planted are to be entered on the map of the forest. Part Two, the "history" book, contains convenient headings for a general record of the various forest activities. Such are : i. Reconnaissance and boundaries: a running record of the reconnaissance done and proposed, be it for timber, grazing, or what not, and of the changes in boundaries and the demarcation in the field of the boundaries. 2. Methods of cutting and planting: a running record of silvical observations in natural and artificial regeneration. 3. Forest protection: a running record of all important forest menaces; the method and success of the combat with them. Such are: (a) Fire. (b) Storm. (c) Frost. (d) Drought. (e) Fungi. (f) Insects, etc. Chapters can be added at will for the other forest activities covered in a forest plan (see Section 2), such as: 4. Administration. 5. Grazing. 6. Permanent improvements. 7. Uses of forest land. 8. Utilization of forest products. (a) Methods of logging. (b) Methods of saw-milling. (c) Markets and prices of stumpage and lumber. (d) Utilization of by-products. (e) Impregnation of wood (wood preservation), etc., ad lib. o. Game and the chase. 136 THE THEORY AND PRACTICE OF WORKING PLANS 10. Money returns of management. (a) Gross income and expense. (b) Net income. ii. Personnel relations. 12. Miscellaneous data. Such a control book, together with the summarized annual cutting and planting plans, corrected maps, and the marginal notes and corrections in the plan itself, forms a perfectly adequate basis for undertaking the periodic revision. The thoroughness of the revision depends on the correctness of the original plan. Only rarely should it be necessary to rewrite the entire plan. Those portions which come under "Orientation," such as physiographic features, social and indus- trial features, and under "Foundation," such as forest descrip- tion, division of area, etc., can either be incorporated directly in the new working plan, or else reference made to the original working plan covering these portions in detail. In matters of yield determination and distribution as em- bodied in the general cutting and planting plans, the revision is essentially a recalculation and reallotment. The preliminary of every revision should be a working-plan conference to review the plan for the working period just passed and to make suggestions for the ensuing period. The digest of this conference should be incorporated in the revised working plan. If the forest is essentially even-aged, the revised working plan should contain under "Orientation": "History of forest with important changes," a diagrammatic presentation of the distribution of the age classes, showing graphically the gradual approach (presumably) towards normality in this respect. This may be shown either by means of a curve or by means of pro- portionate blocks (see Chapter I, Section i, "Distribution of the Age Classes"). PART TWO PRACTICE OF WORKING PLANS PRACTICE OF WORKING PLANS CHAPTER I IN EUROPE SECTION ONE GERMANY The chief States of Germany from the standpoint of forestry are: Prussia, Bavaria, Saxony, Wurttemberg, Baden, and Alsace-Lorraine. For each of these will be given, after a sum- mary of the salient conditions, such as size of country and forests, topography, species, markets, etc., a brief review of the history of working plans, the chief foundations of plans, the methods of regulating the yield, and the prescriptions for control and revision of the working plan. The same scheme will be followed for the data about France and Austria (Sections 2 and 3). I. Prussia Prussia is by far the largest of the German States, with 86,118,526 acres, or about 65 per cent, of the total German Empire. Of these 86,118,526 acres, 20,427,179 acres, or 23.72 per cent, are in forest. Prussia contains widely varying topography, from the very characteristic plains of the northeast to the lesser ranges along the Austrian frontier (Riesengebirge) and in the east- central portions (Harz, Teutoburger Wald, Taunus, etc.). 137 138 THE THEORY AND PRACTICE OF WORKING PLANS If one considers Germany as roughly divided into three main forest regions by a line from the corner of Bohemia, at Eger, northward through Hannover into Liibeck on the Baltic, and another line from Hannover westward to Amsterdam, the large northeast block may be called the pine region, the small north- west block the heath region, and the remaining southwest block the hardwood-spruce-fir region. Practically all of the pine region is contained within Prussia, and this explains the pre- ponderating percentage of Scotch pine — -60 per cent as against 12 per cent of spruce and fir, 5 per cent of oak, 15 per cent of beech, and 4 per cent of birch and alder— in Prussia. The markets for Prussian forest products are so excellent as to admit of the profitable placing of all classes of timber with only minor exceptions. During the nineteenth century the period method of regulat- ing the yield ("Fachwerksmethoden," i.e., "Framework Meth- ods" — see Part One, Chapter II, Section 3, Method No. 17) pre- dominated in Prussia. At first, owing to the influence of G. L. Hartig, it was a strict volume-period method (" Massenf ach- werk," i.e., volume framework). The official instructions of 1819 provide a detailed allotment by volume and classes of material for each of the six periods of the 120-year rotation. The im- practicability of such calculations without adequate bases soon brought a change from Hartig's strict method, the more so since such slow progress was being made toward the goal of having working plans for each forest. Therefore, in 1836, after a provisional regulation of the yield had been accomplished between 1826 and 1835, a new order for regulating the yield was issued which remained in force almost to the end of the century. Though still based on the volume-framework method, the calculation of yield was simplified, and the equality of area was also taken into consideration together with a correct dis- tribution of the age classes and the formation of cutting series. With the introduction of the factor of area, the volume-period method (Massenfachwerk) fell into abeyance and the combined period method (Kombinierte Fachwerk) came to be used for less THE THEORY AND PRACTICE OF WORKING PLANS 139 regular stands, the straight area-period method (Flachenfach- werk) for the more regular conditions.* Of late the calculation of yield has been more and more confined to the ensuing period (the I period), paying little or no attention to the periods following (periods II, III, IV, V, and VI). The general stand table is combined with the general cutting plan, and takes the following form: Column ia Block and compartment. " ib Subcompartment. " 2 Soil description. " 3 Site quality. Average height 4 Average age and age limits. 5 Form of mixture (scattered, groupwise, etc.). 6 Percentage of chief species in mixture. " 7 Defects and diseases. 8 Percentage of stocking (density). Area of the whole compartment. Species. ' over 1 20 years IOI-I20 " 81-100 " 6i- 8o " 41- 6o " 21- 40 " I— 20 9 10 11 12 *3 14 IS 16 T 7J 18 J 9 20 21 22 2 3 24 2 5 Area by Age Classes area in hectares. II III IV V VI Unstocked blanks Period in which to be cut. Present Stands growing to be cut J stock in the I j Species period. Volume at the middle of the period in Cutting area in hectares, [cu. metres. f Total in cu. mtrs. I Per hctr. in cu.m. Increment per ct. * For outline of Prussian working plan, see Part One, Chapter III, Section 2. 140 THE THEORY AND PRACTICE OF WORKING PLANS Column 26 Cutting area of the II period in hectares. " 27 Silvicultural system of cutting. " 28 Species to be planted. " 29 Area to be planted (of that given in columns 18 and 25). " 30 Remarks and necessary additional details. The block and the ranger district usually coincide. Working figures (working circles, "Betriebsklassen") are segregated when- ever there are salient differences in species, rotation, or method of management. The block is subdivided into rectangular units called " Jagen" ("hunts") in the plains, "Distrikte" ("districts") in the moun- tains. The boundaries are roads or topographic features (ridges, streams, etc.). The average size in pine stands is from 49.4 to 74.1 acres; in spruce stands, from 24.7 to 49.4 acres. Subcompartments are not segregated for minor differences, and never for less than 2.47 acres (1 hectare). To insure continuity of records the numbers and boundaries of blocks, compartments, etc., are not changed except for urgent reasons. The soil and rock description is usually taken directly from the geological survey maps. The site quality is usually gauged by means of the yield tables published by the experiment station. The average height is determined by hypsometer measurements of representative trees in the main stand. In uneven-aged stands in which the age classes blend one into the other, the age limits and average age are indicated; where the age classes are widely divergent (e.g., very young and mature) they are entered separately. Great weight attaches to the age class and area table. The area is reduced according to per cent of stocking, i.e., stands whose density is less than .8 are reduced proportionately in area. The areas of each species, in pure stands, are entered separately; this is why column 10 immediately precedes columns n to 17. The criterion of cutting the sustained yield is the normaL THE THEORY AND PRACTICE OF WORKING PLANS 141 area of the period. This is determined by the proportion of the period to the rotation which is usually — = f. An annual sustained yield is not required, but, under regular conditions, the periodic yield must be sustained even for the individual blocks; under irregular conditions more than the normal area can be cut if there is an excess growing stock, and vice versa. With species requiring a long period of regeneration (e.g., natural regeneration by shelterwood-selection method requires often forty years) the areas are allotted in detail for the I and II periods, but not the volumes. The cutting is virtually restricted to the stands indicated for the I period. The manifest impossibility of selecting such stands twenty years in advance and then barring all the others has led to a universal demand for the "Opening of the II Period." The choice of stands for the I period, i.e., the stands to be cut during the next twenty years, is prescribed as follows: Mature stands and defective stands are chosen first. Without undue sacrifices the object to attain is the equalization of the age-class distribution by smoothing out the age differences between sub- compartments (unless they are extreme), but not by having too large adjacent areas of the same age class, because of the in- creased danger from fire, insects, windbreak, etc., in coniferous stands especially. Cutting series are, therefore, advised and so many points of attack that each cutting area will have become stocked with young, thrifty growth before the adjacent area is cut. This usually means a wait of twenty years. The rotation for the chief species is determined for all Prussia, hence only departures therefrom need detailed explanation and justification. The yield or allowed cut for the twenty-year period is the growing stock on the cutting areas of the I period plus the increment thereon during ten years (half the period). This growing stock is estimated by calipering, either all the trees, or a certain per cent thereof, if conditions are sufficiently uniform. 142 THE THEORY AND PRACTICE OP WORKING PLANS The volumes are then calculated from volume tables. The volume of stands of the younger age classes is, if sufficiently regular, taken directly from yield tables, or by means of sample areas.* The increment per cent is usually taken directly from the yield tables. The allowed annual cut is then found by dividing the volume of the entire I period by twenty. A separate cutting plan for thinnings is drawn up. The yield in thinnings is approximated from past experience. This includes the accidental yield through drought and windfall. The regulation of yield in selection forests is purposely simplified, since these all-aged stands are primarily intended for protection. The division into subcompartments is usually waived; the age classes are only approximated, and the calipering of every single stem is not necessary. The allowed cut for the I period is estimated for each working figure according to the ripeness for cutting. Where the selection forest is a distinct unit of sufficient size (e.g., & block) the average annual increment of the whole is determined and taken directly as the allowed annual cut in so far as there is not a marked excess or deficiency in the growing stock or the condition of the forest or other cogent reasons demand a heavier cutting or vice versa. Where the selection forest has been under regulated management for some time past, experience will dictate the approximately correct annual cut. Control and revision of the working plan are provided for * The field-work is done by younger members of the Service (forest assessors, etc.), sent out by the Office of Forest Organization in Berlin (where also the maps are made and the necessary clerical and computing work done), but working under the direction of the supervisor. It is preceded by a working- plan conference between the district officer, the supervisor, and the forest assessor. This body is called the Taxations Commission. This conference discusses ways and means, is digested and incorporated in the working-plan document (called the " Abschatzungswerk," a bound volume of some 125 pages, manuscript or typewritten, with ample margins for additional notes). The working plan must be submitted first to the Commission and then, through regular channels, to the Minister of Agriculture, whose letter putting the working plan into effect is incorporated in the bound volume. THE THEORY AND PRACTICE OF WORKING PLANS 143 by means of the control book, the chief note-book (Hauptmerk- buch), and the area register. The control book serves the double purpose of checking the estimate and the allowed annual cut. For the allowed cut must be adjusted according as the estimates are shown to be just right, or too high, or too low. If too high, there will be a deficit at the end of the period; if too low, there will be a sur- plus. The allowed annual cut is not strictly maintained; silvi- cultural or market conditions may necessitate a higher or lower cut.* Of course this must be offset by reducing or increasing the cut in the years following. Each cutting is entered in the control book, Part A, where for each Jagen, or District (compartment), there is a page whereon to show the time and kind of cutting, the species, and the amount obtained by classes of material. When the cutting of a stand is finished the result is compared with the estimate and the difference entered in control book, Part Ai, which is arranged as follows: Column i. Block. " 2. Compartment. " 3. Subcompartment. " 4. Year in which cutting is completed. " 5. Estimate in cubic metres by species. " 6. Actual cut in cubic metres by species — from con- trol book, Part A. " 7. Plus difference in cubic metres between columns 5 and 6. " 8. Minus difference in cubic metres between columns 5 and 6. At the end of each yearf a balance is struck, and the result of this comparison between the estimate and the actual cut is * An Oberforster (supervisor) may not exceed the allowed annual cut by more than five per cent without the consent of the district office; over ten per cent requires the consent of the central office in Berlin. f Formerly every three years. 144 THE THEORY AND PEACTICE OF WORKING PLANS applied to the allowed cut as entered in control book, Part C,* which is arranged as follows: Year Cut by Species, in Cubic Metres Allowed Actual Balance ± This balance, be it a plus or a minus sum, is carried forward and used as the basis of the cutting plan for the year following, taking into account the plus or minus divergence of the estimate. At the same time Part C serves as a current record of the annual cuts. It is customary to add brief marginal explanations of the cuts larger or smaller in amount than the calculated yield. The chief note-book (Hauptmerkbuch) is a running history of the forest showing the occurrences, management, measures taken, observations made, etc., to form the basis for a new organization of the forestf and as a guide to new administrative officers just taking charge of the forest. It is divided in two parts — the first, a general part, divided into various headings for the recording of events connected with the history of the forest, observations, and also recommendations, under the following headings : * Part B has long since been abandoned. f This is sometimes supplemented by a " Taxatorische Notizbuch," i.e., a note-book containing data especially concerning the field-work and operation of the working plans. THE THEORY AND PRACTICE OF WORKING PLANS 145 i. Surveying and estimating. 2. Methods and results of cuttings and plantings. 3. Forest protection. 4. Status and servitudes. 5. Miscellaneous: markets, utilization, by-products, the chase, money returns, personnel, etc. The second part of the chief note-book is specific, and con- tains a page for each compartment whereon to record the events and changes affecting it. It is in tabular form, as follows: Column 1 Compartment. it 2 Area. 3 4 1 h Cuttings, * Year. Area. (i 5 Year. tt 6 Method of planting or sowing. ec 7 Species. (C cc 8 9 ■ Plantings. < ~ , . , . ( Amount of seed. Plant material used. 1 x _ . , ( Num. of plants. (c 10 Area restocked. cc 11 Cost aside from cost of the seed. cc 12 Remarks. As a supplement to this, all changes in boundaries, soil utiliza- tion, in the character of the stands through cutting or planting, new constructions such as roads, etc., are entered on a map of the forest. The register of area consists of four parts: (A) The index to all extant maps, estimates, and working plans for the forest. (B) A record of all changes in area. (C) A record of all changes in ownership, servitudes, etc. (D) A record of the changes in the area devoted to the growth of timber. Since the year 1852 there have been detailed instructions for the revision of working plans. Until recently this included not only the regulation of the yield, but also the actual admin- 10 146 THE THEORY AND PRACTICE OF WORKING PLANS istration of the forest. With the advent of frequent statistical reports and inspection trips, this last fell into abeyance. The work of revision is similar to that of a new working plan; the degree of revision necessary depends on the changes which have occurred. Preparatory to the revision, each portion of the forest is carefully gone over to determine its present condition as compared with the condition at the time the estimate was made, in order to form an adequate basis for judging the effective- ness of the measures of the working plan, their further use- fulness, and extent to which they require revision. The results of this examination are presented in brief — oftentimes tabular — form, especially as concerns cuttings, plantings, financial results r changes in area, servitudes, and the like. Simple revisions are made by the Oberforster (supervisor) himself, more complicated ones by men especially detailed, as in the case of the original estimates. All revisions are based on a conference between the officials concerned, following the precedent of the working-plan conference; this conference decides upon the further usefulness of the working plan as it stands, just what revisions are to be undertaken, and along what lines. The following are given as the chief considerations in the revision of a working plan: (i) The correction of the surveys and estimates. The area register and the second part of the chief note-book together with the forest maps posted to date are aids in this. (2) Review of the accomplished cutting and regeneration. The bases of this are the control-book and the chief note-book. As an index to the results of management, the cut is totalled for the period ; in addition there is compiled from Part A 1 of the control-book a comparison of the estimated cut with the actual cut; the areas planted or sown during the period are also sum- marized. (3) Review of the silvicultural method of treatment, the rotation, division of area, etc. (4) Review of the regulation of the yield both in determina- THE THEORY AND PRACTICE OF WORKING PLANS 147 tion and distribution. This may involve a partial or even complete revision of the estimates. (5) The drawing up of new general cutting and planting plans according to the revised regulation. (6) The correction or even redrafting of the forest map. II. Bavaria Bavaria is the second largest of the German States. Of its 18,739,890 acres, 32.51 per cent (6,072,386 acres) are in forest. Bavaria presents widely varying topographic and forest conditions, from the rugged spruce and fir-clad northern ranges of the Alps along the southern boundary, through the varied spruce, fir, and Scotch pine stands mixed more or less with hard- woods, of the central and northern portions, to the extensive stands of pure spruce on the east — the famous "Bohemian woods," low ranges not exceeding 5,000 feet elevation, which form the boundary with Austria — and the magnificent oaks of the Spessart in the north-west corner. The market for timber in Bavaria is very variable. In the more remote localities, such as the Alps on the south or the " Bohemian woods'' on the east, utilization is still, necessarily, incomplete. In the northern and central portions of the kingdom intensive agriculture has brought with it the profitable possi- bility of complete utilization. Systematic forest organization in Bavaria dates from 1830, when the combined period method (see Part One, Chapter II, Section 1, Method No. 17) was adopted by a governmental order.* The period was taken as 24 years instead of the cus- tomary 20 years. The yield was regulated for three periods — 72 years — in advance. The end of the nineteenth and beginning of the twentieth century witnessed a revolution in the forest policy of Bavaria, away from the often excessive conservatism of the early days, towards a more liberal interpretation of the State's economic * "Instruktion fur Forstwirtschaftseinrichtung," June 30, 1830. 148 THE THEORY AND PRACTICE OF WORKING PLANS duty, especially in regard to the increasing tendency to manage the State forests for profit as well as for a future timber supply. This change in general policy has manifested itself in the new instructions for forest adjustment.* These are the most recent of the working-plan instructions for any of the major States, and because of their absolute modernity deserve some- what detailed mention. The objects of forest organization are given as: (i) To give a clear conception of existing conditions in the forest. (2) To deduce from these conditions and the purposes which the forest is to serve the object and methods of management and the determination of the yield. (3) To regulate the yield in detail for the ensuing working period. (4) To control the execution of the plan and to secure statistical data thereon. The working-plan unit (working figure) usually coincides with the administrative unit (forest), but this is not essential; if conditions on two or more adjacent forests are sufficiently similar one working plan may suffice. The working-plan unit (working figure, "Betriebsverband") is divided into districts, and these into compartments. This division is primarily for the purpose of orderly arrangement and easier orientation. The basis of division into districts (blocks) is usually topo- graphic; sometimes, however, matters of status and of servi- tudes cause the segregation of a district. The basis of division into compartments is chiefly silvi- cultural, i.e., differences in elevation, exposure, opening of logging means, formation of a forest mantle against windfall, etc. The actual boundaries are usually topographic — ravines, ridges, etc. — with artificial boundaries — roads, trails, cut-out lanes, etc. — as * "Anweisung fur die Forsteinrichtung in den Koniglich Bayrischen Staatswaldungen," Munich, 1910, Verlagsbuchhandlung Oskar Beck. THE THEORY AND PRACTICE OF WORKING PLANS 149 needed. For mere division of area a width of 3 metres (9.84 feet)* suffices ; where protection from fire or wind also comes into play (formation of windmantles) , the width must be increased accordingly. The determination of existing conditions (the first task of forest organization) begins with the division of each compart- ment into forest and non-forest soil; the latter includes not only those areas unsuited for forest, but also those suited for forest but used otherwise. Where accurate measurements are impossible, as in the Alpine zone, estimates of the relative area suffice. Of the forest areas, those are to be distinguished whose yield is naturally very slight (Alpine type) or, for reasons of protection, cost of logging, etc., do not permit of complete, regular utilization. The compartment is divided into subcompartments. The basis of this division is the individual stand. On the stand as the ultimate unit is built up the entire management. The stand, or subcompartment, must be a unit as regards site, soil quality, species, age, and character (growth, density, health, etc.). A stand must differ in at least one of these features in order to be made into a subcompartment. However, all minor differences are to be disregarded. The minimum size of a sub- compartment is usually 1 hectare (2.47 acres). In coppice and in selection forest the segregation of stands (subcompartments) is often impossible, and the compartments must suffice. Wherever possible the subcompartment boundaries are to be topographic features or roads, trails, etc. Where these do not suffice, lines are cleared to a width of 1-2 metres (3.28 to 6.56 feet) and rings of white paint put on the border trees. In uneven-aged stands the average age as well as the age limits is to be given. Throughout the greatest attention is given * In Saxony the main compartment lines running north and south (AVirt- schaftsstreifen) average 9 metres (29.52 feet); the secondary compartment lines running east and west (Schneisen) average 4^ metres (14.76 feet). 150 THE THEORY AND PRACTICE OF WORKING PLANS to the presentation of the age classes in their relation to area by i, species, singly and in mixture; 2, site qualities; and 3, density of stocking. These are shown graphically by means of diagrams. The reason of this attention to the age- class relation is that in even-aged high forest it is made, in conjunction with data on the thriftiness of stands and their suitability to the chosen site, the basis of regulating the yield and of judging the progress towards a normal forest. In coppice with preponderating stand- ards ("Oberholzreichen Mittelwald") and in selection forest a presentation of the age classes is seldom practicable; the most that could be done would be a summary of the area occupied by each age class within, the same (uneven-aged) stand, and this gives no adequate basis for judgment. Detailed estimates are confined usually to those stands intended for cutting during the ensuing working period of ten years. Ocular estimates suffice if conditions are regular and there are available data on cuttings of, or yield tables for, similar stands. In all other cases caliper measurements either of sample plots or of every tree, as the irregularity of the stand may neces- sitate, are required. The increment is to be determined for the next twenty years, because it is a fundamental principle that, at the end of twenty years at the latest, the working plan is to be completely revised, growing stock, increment, and yield redetermined. However, only half the increment for the twenty years is to be added to the present volume of the stands to be cut, since at the end of the first decade half of the stands so designated will have been cut and be without further increment (see diagram, Part One, Chapter II, Section 1). The increment is taken either from suitable normal yiexd tables or as the current annual. The former is simple ; the latter, in irregular and overmature stands, more reliable. The mean annual increment can be used if, by investigation, it has been determined what relation with increasing age and on different site qualities the current annual increment bears to the mean annual. THE THEORY AND PRACTICE OF WORKING PLANS 151 A peculiarity of Bavarian forest organization is the "Char- N acter Index" (" Charakterzahl ") of the stand; -j or the number of stems per hectare divided by the average diameter. This index figure is determined separately for each stand. In the description of existing conditions, special attention is paid to the methods of getting out the timber and suggestions for the development of roads, and other logging methods. Forests only partially accessible demand a plan of logging which includes portions now inaccessible as well as those already opened to management. This plan is usually indicated on a contour map. The real and the normal growing stock are determined (the latter from yield tables), since they show whether there is an excess or a deficit. The relation of normal increment to normal growing stock gives the normal yield by which the actual yield can be judged (see Hundeshagen's formula, Part One, Chapter II, Section i, Method No. 7). On the basis of conditions as they exist, the general rules of management are then formulated according to the objects which the forest is to serve. A decision must therefore be reached as to species, form of stands desired, silvicultural systems, working figures ("Betriebsklassen"), and the rotation to be adopted. Finally the cutting area for the next working period must be fixed. A working figure ("Betriebsklasse") is that portion of one or more administrative units ("Betriebsverbande," forests) varying sufficiently from conditions on the rest of the area to warrant a separate age-class table and calculation of the yield. These variations can be in silvicultural system; in different age of maturity in the species (i.e., different rotations); in marked difference of increment, especially in widely varying elevations; and in important servitudes which influence the course of man- agement. It is to be remembered, however, that too many working figures make the plan unwieldy and difficult of execution, hence 152 THE THEORY AND PRACTICE OF WORKING PLANS only considerable differences are to be taken into account in forming working figures. The instructions for determining the rotation age are a declaration of principles for the new Bavarian forest policy. The rotation age is to be governed by the objects of manage- ment: "Without violating the sustained yield and with due regard to rights of user, to secure the highest possible production of those classes of timber best suited to the needs of the com- munity and of the country as a whole. In addition, the admin- istration is bound to manage the State property entrusted to it in an economic manner, and from the management to secure the highest possible money revenue. "According, therefore, as a forest is not exclusively or pre- ponderatingly intended to satisfy servitudes or to be a protection or a recreation forest, the management must aim at the largest possible production of most demanded timber and at the economic securing of a maximum money revenue." The rotation age must be determined from this standpoint. This determination is not to be confined to the older stands^ but must extend to the younger classes whose origin and growth are often different from that of the older timbers;* for in fixing the rotation age, the period of years required for these younger stands to reach maturity is the most important. The possible rotation period is bounded on the lower side by the merchantability of the sizes secured, on the upper side by the age at which the forest rent ceases to increase. The time of maximum forest rent is therefore the extreme rotation age. As a rule the rotation is to be fixed at that age which produces the maximum amount of timber of medium size, provided the site quality permits. On poorer sites the growth is slower, and * This difference is well illustrated by the Western yellow pine. Measure- ments made by the author near Flagstaff, Arizona, in 1907, show that the mature yellow pine, when in the "blackjack" form, grew much slower than the present "blackjack" of the same size; e.g., at 100 years of age the present "yellow pine" were 13.2 inches diameter breast high; the present "blackjack" 17.95 inches diameter breast high. See Forest Service Bulletin 101, "Western Yellow Pine in Arizona and New Mexico," tables 9 and 10. THE THEORY AND PRACTICE OF WORKING PLANS 153 there the management must be satisfied with the production of smaller sized timber if the rotation is not to be unduly prolonged. Some sacrifices, however, of mere income to the production of larger timbers is proper, since it is the duty of the state to provide for these. But where this can be secured only at the sacrifice of a satisfactory income per cent the prolongation of the rotation is unwarranted. Besides the mathematical calculations of timber and money yield certain other factors come into play, e.g., the influence of the rotation age on the condition of the soil and on the capacity of the stand for natural regeneration, the increased danger of windfall, the decreased vigor with increasing years, the possi- bility of intensive thinnings, and other partly economic, partly silvicultural, partly administrative considerations. Where there are several species with considerable variance in their rotation age, but working figures are not segregated, the rotation age is taken as the geometric mean of the respective areas and rotations. In selection forest a rotation age is difficult of determination because of the widely varying conditions of growth. Diameter is a better guide, i.e., the diameter of greatest productivity determined by measurements of sample trees. Trees which have reached the diameter so determined are merchantable. For every working figure the area must be determined which is to be cut over in the ensuing twenty-year working period. The fundamental consideration is to gauge the cutting areas so that overmature stands and cutting of immature stands are both avoided, but at the same time so that undue vacillations of area cut over do not occur with their bad effect on local market for and needs of timber, employment for men in the woods, and also delayed normality in the distribution of the age classes. If the cutting areas are gauged properly and if, in addition, by means of prompt regeneration, care of soil and growth, the increment in volume and in value is furthered, then the demands of a sustained yield are fully met. 154 THE THEORY AND PRACTICE OF WORKING PLANS In the normal forest the periodic cutting area is constantly Total area TTT1 . , ...... equal to ^ . — X 20. Where the age-class distribution is abnormal this figure can serve only as a means of comparison. In such a case the periodic cutting area is the sum of the stands requiring cutting for silvicultural reasons ("hiebsbediirftig"), stands now mature ("hiebsreif ") or becoming mature in the next twenty years. Where the distribution of the age classes shows a marked departure from the normal, the progress of the cuttings must be gauged for several decades in advance, so as to foretell the progress which the cutting of the present working period will make towards a normal distribution of the age classes. This is to be done schematically according to the following form: Premise. — Rotation = 100 years. Area = 982.2 acres. 1 . ,. • 082.2 Normal periodic cutting area = X 20= 190.4 acres; for silvicultural reasons (overmaturity and poor growth) this has to be increased to 258 acres. This overcutting is then equalized in ensuing periods. (See table next page.) The distribution of cutting areas for the ensuing working period is not confined to assigning half the periodic area to the ten years elapsing before the intermediate revision. The admin- istrative officer in charge of the forest requires leeway in the choice of where to cut; for he must vary his points of attack, use to the full each seed year, secure a mixture of species by advance regeneration of certain ones (e.g., of fir in spruce-fir type; of beech in pine-beech type), take thought of the fluctuations in the demand for timber, aim to secure each year an approx- imately equal revenue, etc. This is possible only if the field of operations is larger than the mere ten-year cutting area. This is secured by allowing the administrative officer in charge of the forest to pick from the periodic (twenty-year) cutting area those areas for the cutting in the ensuing decade which he deems most expedient for reasons of silviculture, cutting sequence (cutting series), administration, and maturity. THE THEORY AND PRACTICE OF WORKING PLANS 155 u If) « N O vd O CM VO O vO 1- *J M > 3^- O i- ^ ■* vO Ov -1 O - •*■ Ov 10 - a> Ov On to cm c<3 O CM vO £ ^ .5 « w h * q CI 10 q q q 00 CM Cfs (j\ Ov to rj\ rt 30 -t ~' ON v£ m C\ *-> >-> CM cv) CM 00 00 CM 00 < M „( C7\ y-i « Ov rt -S Si, 1/5 1/; r-- r-* O CM to O to u >> to 23< f^ to vO OS M f~» to vq ■* f ! 10 q q q q CM Area in 1951 acres -4 vd Cv Ov °0 vd Ov Ov CM to vO Ov CO , ^" ffi N N N N 00 Ov 0> bO C > 1/5 >o tn u «- s a u 00 CM C 10 i-i O «^- O r^ z*< C * On r-» t^» 00 -3- 00 m Ov C 4 10 •* VO 00 r^ m . 00 vq ■?!■ VO ON q c; up q q Ov 00 vO Ov On CM CM . <-" f" Ov vO ON CO ■* Ov CM CV) 00 ON .. — , u5 10 Ih Dm tf) c 5 to 1 n c 3 O O O "■ O >» verag uttini Age X14 O y 5 A c 3 cm w 00 c ) IC to 00 ■+ rr- N C 3 >o 10 CM C-l IO O W •-< O >-" N < <5 N N tO 'J tN. fj\ « M 0 f > ^ + II + ^•ooS < 3 ^•00 CM ^ w q q Less t Perio Area 258 ac jv jl 4- 06 vd vd « CM l/> <3 CI to cs s c " a < 3 *» q >o H lip co r>. vO ^- O CM up CM j\ ~s 4- 06 tj- w 1- DO t^. 06 vd Ov Ov 00 vO CM a»<93 -0 10 ^- vo 'd ^o to Ov vo on to ^h ov 00 ON « .- < 3 3 O O O O O O 00000 a) « 1 O tt" ■O N m O O V 00 t^ VO IO ■* to CM <- Gfl 05 cd » 0^ 1 1 1, « M M J. 1 1 1 1 1 1 1 1 * -0 N 1-1 O C\ X t^ vO lO * tOO M ^ •* -H » H 156 THE THEORY AND PRACTICE OF WORKING PLANS If the sum of the stands so chosen greatly exceeds the allowed ten-year cutting area, those stands are to be excluded and saved for a future decade whose growth is the most thrifty and valuable. By dividing the entire periodic cutting area into the mer- chantable volume thereon, the cut per hectare is obtained. This multiplied by the annual cutting area gives the allowed annual cut in volume. In coppice with preponderating standards and in selection forest regulation by area is not desirable, since it does not do justice to the complicated and varying needs of the tree in such uneven-aged stands.* In such stands the cut for the ensuing working period consists of all trees above a fixed diameter (determined as stated above), in addition the volume of those trees which during the next ten years will reach this diameter and such as have to be removed for silvicultural reasons ("wolf- trees," "snobs," etc.). In the case of coppice with standards there is, also, of course, the volume of the coppice. A tenth of the total amount for the next decade is the annual yield; this is checked by the current increment per cent — the sum of the increment per cents of each diameter class, and by the result of past cuttings. Order and progress of the cuttings are insured by the observance of a cutting cycle. The provisions for renewal of the working plan are as fol- lows: Each plan is drawn up for a period of twenty years, but at the end of the first decade an intermediate revision — or review — is had; at the end of the twenty years a complete revision is had resulting in a new plan. Exceptional circum- stances may necessitate a complete revision before that time, as when unforeseen changes have occurred in the very founda- tions of the plan. Often, however, it suffices in such cases to make provisional changes for the remainder of the working period. Natural calamities — wind, fire, etc. — always require some time, as things are, before the measure of the catastrophe can be properly judged. * Where the undergrowth is too dense to permit calipering, it may be necessary to regulate the yield, even of coppice with standards, by area. THE THEORY AND PRACTICE OF WORKING PLANS 157 The intermediate revisions are to cover the following points: a. Necessary corrections of the methods of determining the yield (checking of estimates, etc.). b. Determination of the cutting areas for the past decade, comparison with the allowed area, and determination of the area for the ensuing decade which again is really that for a period of twenty years. c. Emendation of the plan of management. d. Determination of the volume yield of the next working period (based on a, b, and c). e. The making of a new map of the forest. In the main revisions the task is a similar one, but more exhaustive. The results of the management during the past period — 20 years — are to be compiled and the whole structure of the working plan renewed as may be necessary. Bavaria, in common with many of the German States, has a separate section of working plans in the central office at Munich. This section is charged with the field-work and the office preparation of the plans. The supervisor of the forest concerned is consulted in every feature of the plan; he and his subordinates are charged to assist in the preparation thereof. The bases of the plan as well as the completed plan require the approval of the royal ministry of finance, forest section. The procedure in working plans is as follows: During the working period the supervisor is supposed to keep careful record of such results of management as aid in judging of the volume and value yield. The underlying field data can often be supplemented by him during slack periods of the year. In the last year of the twenty-year working period the super- visor has to report about the execution of the working plan, the experiences gained thereby, and about the essential results of the management, the changes in the condition of the forest, to express himself about the fundamentals of the working plan and to base suggested changes on detailed data. The district inspection officer has to express himself as to 158 THE THEORY AND PRACTICE OF WORKING PLANS this report and these recommendations of the supervisor. The working-plans officer assigned for the task has then, in company with the district officer and the officers of the forest, to go over the forest in detail. On the basis of this trip over the forest, and after due consideration of the proposals made by the dis- trict officer and the supervisor,* the working-plans officer draws up the fundamentals of the new working plan, and the scheme of field-work. Often, of course, some of these fundamentals must await, at least in part, certain investigations in the field; for such points a supplement is to be prepared. The fundamentals as agreed upon at the working-plan con- ference and any supplement thereto, must be approved by the State ministry of finance. In the last year of each decade, also, the supervisor must anticipate the intermediate revision or review by a report on the correctness and applicability of the methods of yield deter- mination and of the rules of management. A working-plan conference and consequent drawing up of the fundamentals of the proposed plan are not necessary in the intermediate revisions. The field-work is done by assistants of the working-plans officer in so far as the forest force cannot be used therefor. The party may be divided into sections, each under the direction of a section chief versed in working-plans procedure. These section chiefs and their workmen are instructed (if necessary in writing) by the working-plans officer acting in conjunction with the administrative officers of the forest. The supervisor has to keep in touch with the progress of the work and the manner of execution. The section chief, on demand, must report thereon to the supervisor. The working up of the field data and the preparation of the working-plan document is the task of the section of working plans in the central office at Munich. As soon as the essentials of the plan are ready in rough draft, they are to be submitted * If their advice is refused the reason for such refusal must be stated by the working-plans officer. THE THEORY AND PRACTICE OF WORKING PLANS 159 to the supervisor of the forest for his review and written rec- ommendations and memoranda. These last are to be incor- porated in the working-plan document. Then the draft of the plan is submitted to the officers of the district and central offices, who must also record any divergent opinions in writing. Finally, all new working plans or main revisions have to be laid before the ministry of finance for its approval, which puts the plan in force. In intermediate revisions it suffices to notify the ministry of departures necessitated from the original plan, before submitting the revised plan to the supervisor for execution. A map of the forest forms an indispensable part of every working plan. No special document is necessary for the intermediate revi- sions; the existing plan is merely amended in the text, if neces- sary by the insertion of extra pages. A part of every revision is a resume of the management dur- ing the working period just concluded. III. Saxony Although small in size— 3,703,271 acres— Saxony is, because of its dense population and great industrial development, the state of third importance in Germany. Despite its dense pop- ulation, 949,813 acres, or 25.65 per cent of the total area, is forested. Saxony is a compact unit, roughly triangular in shape, the low mountains of the Erz Gebirge forming the base and the city of Leipzig the apex. The stands in Saxony are, overwhelm- ingly, pure spruce with Scotch pine stands in the northern, plains portion. The Saxon markets are pluperfect, which explains the suc- cess of the Saxon spruce management with such a low rotation and resulting small diameter.* Forest organization in Saxony is under the control of a cen- * See " Management of Spruce in Saxony," Article V in the series. "Amer- ican Aspects of European Forestry" in "Forestry Quarterly," Volume XI. 160 THE THEORY AND PRACTICE OF WORKING PLANS tral bureau of forest organization (Forsteinrichtungsanstalt) in Dresden. This has worked well, since it has secured uniformity of methods and results and an experienced, well-drilled per- sonnel. It also established for forest organization a definite and correct interrelation with the other branches of forestry — administration, experimentation, etc. As in most of the German states, the regulation of yield was first by the period method. Heinrich Cotta, who system- atized the working plans for the Saxon state forests in the years 1811 to 1 83 1, endorsed both the area period and the combined period methods. Frequent, regular revisions soon obviated the necessity of determining the yield several periods of twenty years each in advance. The period method was therefore aban- doned and the determination of yield confined to the next decade by means of the stand method ("Bestandswirtschaft") (Method No. 16, Part One, Chapter II, Section 1).* The division of area is as far as possible rectilinear, the boundaries being used as roads. Because of the imminent danger of windfall in spruce, the lines are run parallel with and at right angles to the prevailing wind direction. Stands (subcompartments) are segregated down to a mini- mum area of half an acre. The prevalent uniformity of con- ditions permits of tabulated forest descriptions. Site quality is gauged both according to the intrinsic quality of the soil (Stand- ortsbonitat) and according to the quality of the stand growing thereon (Bestandsbonitat) . The two by no means always coin- cide; for the stand growing on a certain site is not necessarily the one best suited to it. The age classes are in twenty-year gradations — each age class is again divided in half so that the age-class distribution is recorded by decades. Owing to the great regularity of the stands, calipering is not ordinarily necessary. Stands less than half of the usual rota- tion of eighty years are estimated from yield tables; stands * For outline of Saxon working plan, see Part One, Chapter III, Section 2. THE THEORY AND PRACTICE OF WORKING PLANS 161 over forty years old are estimated ocularly and reestimated at each ten-year revision. Where clear cutting preponderates, the normal annual cut is taken roughly as the total area divided by the rotation. The proper rotation age is determined by applying the index per cent (Weiserprozent) to the individual stand, i.e., determining the maximum value increment (see Part One, Chapter I, Sec- tion 3). Tables of value increment have been prepared for the whole kingdom of Saxony, based on the prices secured in the open market for the various classes of timber. Saxon forestry foots on the soil-rent basis. In order to show the profits of management on this basis, the net income for the whole forest is compared with the total cost of production. This is done for purposes of forest organization, by determining the timber and soil capital which the forest represents and then showing in tabular form the rate of interest returned thereon for each year by the forest management (Reinertrags- iibersicht) . The normal annual cutting area is maintained as nearly as may be. Under irregular conditions, departures therefrom are necessary. The table of age-class distribution serves as an index to the degree of departure necessary. If the higher age classes are in excess, the annual cutting area is increased; conversely, it is diminished. Hence, a careful exposition of the age-class distribution is of vital importance. The Saxon system, of maximum money returns on the invest- ment, demands that those stands whose index per cent is lowest be cut first. The next most important consideration is the cut- ting series; for the preponderance of spruce, the danger from windfall demands that the cutting areas progress towards the prevailing wind direction. Since the cutting strips are narrow and an interval elapses before the adjacent strip is cut, it fol- lows, as a general rule, that the cutting series are short. How- ever, in order to accomplish this and to avoid the joining to- gether of large areas of practically equal age, it is necessary to liave many points of attack. To secure these, the edge of a 11 162 THE THEORY AND PRACTICE OF WORKING PLANS stand exposed by the removal of the sheltering stand to wind- ward, must betimes be accustomed to the exposure by the for- mation of deep crowns — the so-called forest mantle or wind mantle (see Part One, Chapter II, Section 2). The most important task of the forest organization, as re- gards arrangement of area, is the selection of these points of attack for the cutting series. The further development of the cutting series can, however, be only sketched, since it depends on circumstances which the organizer at the time of drawing up the plan cannot know. The volume of the cut for the working period of ten years is found by ocular determination of the stand on the area to be cut over. The yield to be expected from thinnings is gauged according to the results of the decade past, aided by yield tables, and, of course, with special regard to the needs of the stands. Stress is laid on the continuity of statistical records re age- class distribution, volume of growing stock, yearly cuts in amount and classes of material, the gross income, the expenses, the net income (Reinertrag) , the forest capital, etc. These records have been kept in Saxony since 18 17 and are invaluable aids for purposes of forest organization. In addition to the revisions at the end of the ten-year work- ing period, there are, in Saxony, intermediate revisions in the middle of the working period. The most important features of revision are the entry of cuttings and plantings on the map of the forest; the comparison of the actual cut with the estimate; the necessitated departures from the prescriptions of the work- ing plan, etc. For purposes of forest organization the usual stand map (scale of 1 : 20,000 or 1 : 15,000) showing species, age, classes, and cutting series is used as a base whereon to show the intended cutting areas of the next decade, special planting areas, the cutting series, etc. THE THEORY AND PRACTICE OF WORKING PLANS 163 IV. WtJRTTEMBERG Wurttemberg and Baden between them contain the Black Forest, that long line of lesser ranges flanking the Rhine on the east. Wurttemberg has an area of 4,819,958 acres, of which 30.77 per cent or 1,483,025 acres are forested. Wurttemberg is traversed by various lesser ranges which give to the whole kingdom a rolling topography. The species corresponding thereto are preponderatingly spruce and fir. The splendid development of the timber market in Wurt- temberg and of the road system necessary to get the timber on the market puts Wurttemberg on a par with Saxony as regards financially, profitable management. Wiirttemberg's systematic forest organization dates from the year 1878. The experience gained during the years follow- ing led to a sweeping revision'in 1898. The period method was dropped, with its impractical endowment of areas in advance for each twenty-year period of the rotation. Attention was centred on the segregation of stand units, i.e., subcompartments and the regulation of yield based thereon rather than on the area of arbitrary divisions (compartments). The condition of the individual stand was made the criterion of regulation; the yield is no longer determined in advance for the whole rotation, but usually for only the first period of 20 years, exceptionally for the second period also. A . Area Normally, the cutting area of the I Period = p . — X 20. Exceptions are necessitated under abnormal conditions such as an excess or deficit of merchantable timber, etc. With thrifty stands and a proper distribution of the age classes (in ten- year gradations) the sum of the merchantable stands will auto- matically aggregate the periodic cutting area. In the choice of stands for regeneration, great attention is paid to the formation of proper cutting series, just as in Saxony (see above).* * See also Article VI of the Series "American Aspects of European For- estry," "Forestry Quarterly," Volume XI. 164 THE THEORY AND PRACTICE OF WORKING PLANS The process of forest organization is summarized as follows: After rotation, silvicultural system, and species have been set- tled upon and the actual condition of each stand (subcompart- ment) accurately determined, the first period of twenty years is endowed with the proper area of subcompartments according to the principles outlined above. Then for the next decade the stands on half the period area are accurately estimated (cali- pered). Since there are always unlooked-for contingencies re- quiring cutting of areas aside from those provided for in the plan, an amount based on past experience is allowed for such emergencies. A separate area plan is drawn up for thinnings. Forest organization in Wurttemberg is in a state of transi- tion from the period method to that by stands; it is not quite "off with the old" as yet nor "on with the new." i V. Baden The Grand Duchy of Baden is the neighbor state of Wurt- temberg. It.has a total area of 3,725,007 acres, of which 1,402,- 454 acres, or 37.65 per cent, are forested, the highest percentage of any of the German states, only excepting the petty princi- palities ct Waldeck and of Reuss.* The Biack Forest range traverses Baden from north to south like a backbone. The preponderating species are therefore spruce and fir (whence the name "Black Forest") except in the norther plains and along the Rhine, where there are stands of hardwoods (mostly coppice) and of Scotch pine. As in Wurttemberg, a magnificent road system makes acces- sible every portion of the forests; a ready market exists for almost every class of products. In Baden, too, forest organization developed from the vol- ume period method (Massenf achwerk) . But under the pre- vailing forest conditions of the Grand Duchy, which is charac- * These have 38.18 and 37.74 per cent, respectively. The average for the whole German Empire is 25.88 per cent. THE THEORY AND PRACTICE OF WORKING PLANS 165 terized by splendid natural regeneration,* especially of fir, the method did not prove feasible; for the process of natural re- generation requires a much longer time than the twenty-year period (usually from 30 to 50 years). Since i860 thoroughgoing revisions of the working plan are undertaken every ten years. They are based on the results of the past decade; the actual cut, as compared with the estimates; the effect thereof on the condition of the forest, etc. The present working-plan procedure dates from 1869; its characteristic features are as follows: Foundations. — Before the working-plan data are secured, the forest is carefully gone over by the officials who are con- cerned in the organization of the forest. This also involves the critical scrutiny of the existing working plan in all its parts. This examination lays stress on the division of area, the de- scriptions of site and of stands, the estimates of growing stock and of increment, the results of the previous management, and the basic provisions of the future proposed management. The general forest description and other "Foundations" must set forth clearly the site conditions, the existing species, the silvicultural system, the rotation, the rules of management, etc. The special forest description gives briefly, for each com- partment and subcompartment, the area, volume by species, the character and condition of the timber, and the increment. The estimates of volume are most carefully executed by- special measurements in those compartments undergoing re- generation, i.e., in the oldest stands; in the remainder the volume is usually determined roughly by means of yield tables, past experiences, and sample areas. For the determination of the increment yield tables and past experiences are used; also increment borings on suitably chosen representative trees of the stand (see Part One, Chapter I, Section 1). Regulation of Yield. — The yield is determined according * See " Natural Regeneration in the Black Forest," Article VI of the Series "American Aspects of European Forestry," "Forestry Quarterly," Volume XI. 166 THE THEORY AND PRACTICE OF WORKING PLANS to Heyer's formula (see Method No. 9, Part One, Chapter II, Section 1). The basis and gauge of the yield is the acutal in- crement. The regulations of 1869 prescribe this as the current increment "as it will probably be in the next decade." Recog- nizing the difficulty of an exact computation, and the restric- tion of application to the merchantable yield, it seemed ex- pedient to substitute for the current increment the mean annual increment. The normal growing stock is calculated by the formula r nv = m X - . Similarly the actual growing stock of uncut stands is taken as the product of mean annual increment, age, and density of stocking (in decimals). More than the increment is to be cut if the growing stock is in excess of the normal, and the cutting thereof is silviculturally and economically advisable. Less than the increment is to be cut if the growing stock is less than the normal. The more rapidly in the latter case the growing stock can be raised to normal by a saving of the increment, the better it is, provided that no substantial economic losses or silvicultural errors are caused thereby; in no case is the period of equalization to be longer than the rotation. With due regard to these principles the annual cut is to be fixed according to the local economic and silvicultural necessi- ties (emphatically including the wishes of the owner), not for- getting the desirability, especially in forests owned corporately or communally, of a steady annual yield: violent fluctuations In the yield react adversely on the owner's opinion of the working plan. A gradual augmenting of the yield will suit the owner far better than a sudden increase followed by a slump. Furthermore, it must be remembered that in almost every decade there are unforeseen contingencies and demands for timber which necessitate additional cuttings, in excess of the annual cut as fixed; wherefore, in case of doubt, the allowed annual cut should be set somewhat lower than is mathe- matically necessary. THE THEORY AND PRACTICE OF WORKING PLANS 167 The allowed annual cut in coppice and coppice with stand- ards is solely by area and not by volume. Statistical Record has, since 1869, been in intimate conjunc- tion with forest organization so as to have systematic data on conditions and results, to simplify the working-plan documents and to be applied as precedents, good or bad. The vital statistical records are: The history of the particu- lar administrative unit (origin, composition, status, etc.); the description of the forest according to the subheads: forested area, topography, management, forest utilization, logging methods, forest protection, the chase, money returns, etc. These data are compiled for the first time by the adminis- trative officers of a forest, but the continuation and supplement- ing thereof is done by the forest organizer at revision of the working plan. VI. Alsace-Lorraine These provinces conquered from the French in 1870-71 con- tain the major part of the Vosges Mountains, a long line of lesser ranges flanking the Rhine on the west. Together they have an area of 3,584,711 acres, of which 1,086,385 acres, or 30.31 per cent, are forested. The topography is rolling, becoming mountainous in the southern portion of the Vosges. The species correspond closely to the topography: coppice hardwoods and Scotch pine in the more level portions; fir and beech and some spruce in the mountains, with oak on the foothills. The road development and the timber markets of these provinces are rapidly approaching the same degree of perfection as already exists in the neighboring state of Baden. When Germany gained control of these provinces in 187 1 it became necessary at once to have provisional working plans for each administrative unit. These were made by the adminis- trative officer in charge of the forest, passed upon by the in- specting (district) officer, and finally approved by the minister. 168 THE THEORY AND PRACTICE OF WORKING PLANS The essentials of these provisional plans are the division of area,, plan for roads and trails, determination of the method of man- agement and of the silvicultural system, fixation of the rotation, etc. As soon as possible following thereupon, regular working plans were constructed, based on these provisional plans. Re- vised plans are also prescribed at the expiration of each twenty- year period, after substantial changes in area or growing stock, and in cases of transition as from high forest to coppice and vice versa. The regulations of 1904 lay stress on the following features of forest organization.* Division of Area. — The segregation of compartments is done in conjunction with the laying out of the logging and wagon roads and the trails. The area in coniferous stands is not to exceed 24.70 to 37.05 acres, in hardwood stands from 37.05 to 49.40 acres. For coppice and coppice with standards the forest is divided into annual cutting areas; for there the regulation is by area alone. In communal forests one-quarter of the area is set aside as reserve, dating from the ordinances of Colbert in 1669, which provide that in forests owned by the church, or alienated in mortmain, or owned by communities or by parishes, one-fourth of the area is to be reserved from cutting; the balance to be divided into regular cuts ("coupes regulees"). There are no binding prescriptions for the division into subcompartments. In larger forests with various species the minimum size is to be 2.47 acres (one hectare). For segrega- tion on the basis of age differences or differences in density of stocking, a minimum of 4.94 acres suffices. Subcompartments are segregated only if the area requires distinctive treatment. Stands in process of regeneration are to be segregated down to a minimum size of 2.47 acres. The subcompartments are indicated on the ground by * "Vorschriften fur die Aufstellung und Revision der Forstbetriebsein- richtungswerke," Strassburg, 1904. THE THEORY AND PRACTICE OF WORKING PLANS 169 means of stakes and ditches at the corners and are entered in the maps. Maps: Field surveys are usually confined to interior lines, since reliable geodetic maps are available for both provinces. The forest map is usually on a scale of i : 25,000 and shows the species by different colors. The cutting areas are indicated on the map for the I and II period — i.e., for the next forty years — by means of cross hatching, unbroken lines for the I period, broken lines and dots for the II period. Forest Description is to be short and confined to the charac- teristic features such as status, boundaries, surveys, etc.; stand and site conditions; the occurrence and interrelation of the chief species; past management and results; future, intended management, especially species, silvicultural systems, rotations, formation of cutting series, regenerative methods, roads, mar- kets, by-products, the chase, etc. Regulation of Yield. — The criterion of yield is the normal periodic cutting area. If the same rotation applies throughout the forest this area = the total area of the forest X 20 -r the rotation. Where there are several rotations, the normal peri- odic cutting area is determined for each species according to the ratio of the period to the rotation. The total cutting area is then secured by adding together those of each species. Stands of the I period in which regeneration cuttings have begun are entered with reduced areas in proportion to the per- centage of the stand removed. A distribution of cutting areas for the III, IV, V, and VI periods is obsolete; these stands and their areas are merely entered in the column headed "later periods." In deciding on stands for the I and II period especial regard is paid to age and thriftiness, and, in coniferous stands, on the formation of small cutting series. The period method, strictly speaking, is therefore no longer used in Alsace-Lorraine. The long period of regeneration — often 30 to 50 years — re- quires th Q assignment of stands for two periods — 40 years— in advance. The stands inte ided for cutting in the I and II 170 THE THEORY AND PRACTICE OF WORKING PLANS period are usually calipered; those of the II period, if suffi- ciently uniform, may be estimated by means of sample areas; thereto must be added the increment calculated to the middle of each period. The volume of the allowed annual cut is 1/20 of the period volume calculated separately by species. In communal forests one-fourth of the allowed cut is to be subtracted (see above) . In selection stands the yield is determined from the actual increment and the relation of the actual to the normal growing stock according to Heyer's formula (Method No. 9, Part One, Chapter II, Section 1). In order to determine the actual grow- ing stock, all the trees above 3^ inches (8 centimetres) in di- ameter are calipered. The actual increment is determined by increment borings of trees of various diameter classes; the ri normal increment according to the formula—, where i = the mean annual increment. The number of years in which the excess or deficit of the growing stock is to be taken up is determined for each individual case according to the particular circum- stances. The cutting cycle (period between cuts) is not to be placed too high: usually 7 to 9 years. Planting and Road Plans are to form a part of every working plan. The planting plan embraces not only the methods of artificial planting, of nursery practice, and the source of plant material, but also the care of cutting areas and of young plan- tations. Revisions of the Working Plan are to take place in the middle of the 20-year period. The kind and degree of the revision to be undertaken follows from the demands made of the plans and the changes which, through the methods of management pur- sued or through outside influences, have occurred during the first half of the working period (10 years). At the end of the working period (20 years) an entirely new working plan is drawn up (see above). The essential points to be considered in revision are: Changes THE THEORY AND PRACTICE OF WORKING PLANS 171 in area, the actual annual cut as compared with the allowed annual cut as regulated, the comparison of the volume yield of stands cut over with the estimated volume thereof, the unfore- seen cuttings not provided for in the plan, the yield from thin- nings, the execution and cost of plantings and sowings, the changes in servitudes, the relation of by-products to the scheme of management, the completion of road and trail building, etc. SECTION TWO FRANCE The total area of France is 132,492,776 acres, of which * 18.17 per cent are covered with forests: 5,187,000 acres, or 77 per cent, hardwoods; 1,583,270 acres, or 23 per cent, coni- fers. Of these 6,770,270 acres the State forests comprise only 12 per cent; the communal forests under State management, 20.2 per cent. The forests of France proper may be divided roughly into (1) plain and (2) mountain forests. Under (1) may be included the Parisienne zone, the Gironde, the Provencale; under (2) the Vosges, Jura, Alpes, Plateau Central, and the Pyrenees.f Cor- responding to the topography the chief species are either oak, beech, birch, elm, chestnut, and pine, or, in the mountains, fir, spruce, pine, larch, and beech. La Savoie is the only region of France where the spruce dominates in the forests. In the Pyrenees and along the Mediterranean coast species are found distinctive of the region, such as hook pine, d'Alep pine, mari- time pine, cork oak, live oak, etc. The timber markets of France, while not so intensely de- veloped as those of Germany, are still almost as omnivorous as * From Hiiffel: "Economie Forestiere." t For further details see Article: "European Study for Foresters" by A. B. Recknagel and Theodore S. Woolsey, Jr.; "Forestry Quarterly," Vol- ume X., No. 3. 172 THE THEORY AND PRACTICE OF WORKING PLANS those of the neighbor State on the east because of the relatively- smaller per cent of forest land.* The methods of forest organization in France are in striking contrast to those in Germany. The conditions of forest owner- ship have strongly influenced French forest organization or "Amenagement," as it is called. Hitherto it has been gener- ally assumed that privately owned forests are not suited to a sustained yield management. It was thought that the difficulty of foretelling future needs and the uncertainty of predicting yields were in contravention to the basic principles of forest management for private ends and that, furthermore, the grow- ing of timber, especially of the larger sizes, is primarily the duty of the state and of* the communities. These views coincided with the actual conditions of forest ownership: in the forests owned by the state high forest is the rule with a high rotation;! the forests owned communally are usually coppice with stand- ards; and tr-3 forests privately owned, straight coppice. But of late conditions have changed substantially: the increased prices of forest products and the decreased interest rate have made the growing of the larger sizes of timber profitable also for the private owner. The chief features of French forest organization are the division of area, the methods of determining the yield, the dis- tribution of the periodic cutting areas, and the determination of the allowed annual cut. Division of Area. — The state forests and the forests under state control are divided into series. These series are adjacent forest areas with uniform market conditions and a sustained yield; they often coincide with the ranger district (triages). "By a series is understood a portion of the forest, intended to be covered by a special plan of utilization and consequently to furnish a series of annual cutting areas." $ The series are subdivided into sections. "By a section is * In France 18.17; 25.88 per cent in Germany. f 140, 160, 200, and even 240 years. {Tassy: "Etudes sur l'amenagement des forSts." THE THEORY AND PRACTICE OF WORKING PLANS 173 understood a portion of the forest distinct from the rest by the method of management" (coppice, regular high forest, selection high forest, etc.). Accordingly, the segregation into sections is based, preferably, on the method of management (regime) and on the silvicultural system (mode de traitement). The series are further divided into periodic cutting areas called ' ' affectations . ' ' The division by silvical units, i.e., stands, is called the par- celle. These parcelles are the basis of the whole forest organiza- tion and of the course of the management. In each forest dis- trict (canton) those portions are to be segregated which differ in species or in age, or in site, exposure, growth or density of stand, in such a way that each portion or parcelle can be handled identically throughout. In the records the parcelles are classed as divisions if they are permanent, as subdivisions if only temporary. The parcelles are marked by stones at the intersections of the boundary lines; the boundaries themselves by narrow cleared lines or by signs. The forest description of the individual parcelles is accord- ing to the following form.* Column i. Cantons, i.e., forest district, or block. " 2. Divisions and subdivisions. " 3 / Volume \ subdivisions. " 4 ) Contents of the ( divisions. " 5. Site and elevation. " 6. Exposure. " 7. Slope. " 8. Soil. " 9. Percentage of each species in the mixture. " 10. Age. " n. Character of the stand. " 12. Growth. " 13. Remarks. Method of Determining the Yield.— The yield is determined * Called "Etat descriptif des divisions et subdivisions." (1 12 IC 13 it 14 CI IS (I 16 (C 17 a 18 174 THE THEORY AND PRACTICE OF WORKING PLANS by the area period method as appears from the following tab- ulated form for working plans.* Column 1. Number of the affectation. " 2. Names of the cantons. " 3. Divisions and subdivisions. " 4. ) . . . , ^ ( subdivisions. V Area in hectares 01 the I .. . . 5. ) ( divisions. " 6. Site, exposure, soil. " 7. Percentage of each species. " 8. Density and growth of the stand. 9} A (present. " 10 J I at the time of cutting. 11 I ( final cuttings ( ordinary. ^ ( in hectares ( extraordinary. Thinnings, in hectares. jj . 1 j final cuttings { ordinary. / in hectares ( extraordinary. Thinnings, in hectares. TTT . , . . , ( final. Ill period cuttings, m hectares - ^ , . . " ioL 7 . , . • , (final. (( y hlV period cuttings, in hectares - ^ . . " 21 ?. T . . . . , i final. u , S period cuttings, in hectares! ,. . 2^L_ . , . . , (final. tc r VI period cuttings, in hectares^ ,. . " 25. Remarks. The number and length of the periods vary with the species and the locality. For oak in central France eight periods of 25 years each are formed; for beech usually six periods of 20 years each; for fir four or five or more periods of 30 years each. The * Reglement general des exploitations par periode pendant la premiere revolution (revolution equals rotation). See also Methode de Masson and Methode de 1883 (French Mvthod), Nos. 3 and 10, respectively, Part One, Chapter II, Section 1. THE THEORY AND PRACTICE OF WORKING PLANS 175 approval of the period number and length requires the approval of the minister.* The rotation age is only fixed tentatively "without attempt- ing to fix it definitely by applying experiences whose value is often only specious." f For the state forests a rotation age is chosen which corre- sponds to the maximum possible yield of the most useful classes of materials. This has resulted in a conservative tendency showing itself in the present conditions of the forests of France and of Alsace-Lorraine. In general the adopted rotations are distributed as follows: Reg. high forest . Select, high forest Rotation Age Under 100 years 100-150 years 35.7% of total area 9.8% of total area 150-200 years 43.1% of total area 43.7% of total area 21.2% of total area 46.5% of total area Distribution of the Periodic Cutting Areas. — This is the most characteristic feature of French forest organization. The periodic cutting areas are to be so arranged that they comprise the area of each period without a break or interrupting area of another period. This is in direct contradiction to the aim of the German forest organization, particularly of the Saxon. The reasons given for this distribution are simplicity in regeneration cuttings; of regularity of formation of the periodic cutting areas with their narrow side toward the prevailing storm direction and bounded wherever possible by roads. Tassy in his " Etudes sur i'amenagement des forets" lays especial stress on the un- desirability of breaking up the periodic cutting areas into cut- ting series 4 This principle has been followed in the working plans for the * Formerly of the Emperor himself by a decree, t From a French working plan. t Tassy, troisieme etude, Chapter IV, Section 3, "formation des affec- tations conformement aux regies d'assiette." 176 THE THEORY AND PRACTICE OF WORKING PLANS state and communal forests. The periodic cutting areas are systematically grouped in the maps and on the ground. The immediate consequence is that many stands are cut not at the time of their maturity, but too soon or too late; furthermore, the reproduction cuttings become very large and thus, in the future, there will be extensive stands of even age. Both con- sequences are attended with drawbacks of management (in- creased danger of windfall, fire, insects, fungi, etc.), even though these are less in France by reason of the prevalence of the nat- ural regeneration and the predominance of hardwoods than they would be, for example, under German conditions. Determination of the Allowed Annual Cut is both by volumes and by values. For the cuttings of the first period a special cutting plan or felling budget is drawn up (Reglement special des exploitations pour la premiere periode), in which the cutting areas and volumes are entered, arranged according to the di- visions and subdivisions and according to final cuttings (Coupes principales) further divided into Coupes ordinaires and Coupes extra ordinaires, and thinnings (Coupes intermediaires). The volume of the Coupes principales is determined first by caliper measurements entered separately by species; the volumes are then computed from volume tables based on the contents of sample trees of the various diameter classes. The increment for the years elapsing between the estimate and the cutting is disregarded in the computation. Thinnings are regulated by area; their volume is taken from the experience of the preceding decade. To the determination of the allowed annual cut by volume is added one by values (Evaluation en argent de la possibilite) . This is based on the estimate of the classes of timber which is made for each species and for each class on the value according to the prevailing prices (prix sur pied par nature de marchandises). Adding the values of each class gives the total value of the felling budget. The regulation of yield in coppice and in coppice with stand- ards is by area. Coppice systems have reached a point of de- THE THEORY AND PRACTICE OF WORKING PLANS 177 velopment in France far in advance of that in other European countries. The regulation of coppice dates from the ordinances of Colbert in 1669. The division of area depends on the rota- tion age of the coppice under the standards. In the state for- ests 50 per cent have a coppice rotation of 20 to 30 years; 46 per cent have a rotation of over 30 years; in the communal forests 77 per cent have a rotation of 20 to 30 years, 20 per cent a rotation of over 30 years.* The standards are arranged by age classes and distributed equally on the area. These standards are either two, three, or four times the rotation age (baliveaux de Page, modernes, and anciens, respectively). The yield of standards is determined by the number of stems of each class and is usually accomplished with the utmost regularity. SECTION THREE AUSTRIA Austria, exclusive of Hungary,! contains 74,101,976 acres, of which 24,125,888 acres or 32.6 per cent are forested.^ This puts Austria fourth in the rank of timbered countries of Europe, preceded only by Sweden with 49 per cent forest area, Fin- land with 46 per cent, and Russia with 39 per cent. The ownership of Austrian forests, which has profoundly influenced the development of forestry there, is as follows: State forests n per cent of the total area, communal forests 14 per cent, church forests 17 per cent, private forests 59 per cent.§ Austria can be conveniently divided into five great districts; * For straight coppice 56 per cent of the state forests and 76 per cent of the communal forests have a rotation age of 20 to 30 years. t The differences of race and language have resulted in all but the po- litical separation of the two countries. t In Hungary It is 27.8 per cent; in Germany 25.88 per cent; in France 18.17 per cent. § Data from "Die Holzproduktion Oesterreichs," K. K. Ackerbauminis- terium, 1907. 12 178 THE THEORY AND PRACTICE OF WORKING PLANS these, with their percentage of forested area and the per cent of timber tracts over 2,500 acres in size, are as follows: w nf % of tracts District and included Provinces - /0 " 1 2,500 acres torest area and oyer Danube (Niederosterreich, Oberosterreich) 34-2 44-6 Alps (Salzburg, Tirol, Steiermark, Karnten, and Krain) 41 . 8 41 . 1 Coast (Kustenland, Dalmatia) 29 . 6 37-7 Northwest (Bohemia, Mahren, Schlesien) 29 . 1 65 . 7 Northeast (Galicia, Bukowina) 27.7 69 . 6 Totals 32.6 54.3 of which nearly one-half are tracts of 7,500 acres in size or more; nearly one-quarter, or half, of the half are tracts of 25,000 acres or more. This division corresponds fairly well with the general topog- raphy and the forest conditions. The Alps and the northeast districts (Carpathians) comprise tremendous mountain ranges; the Alps continue in diminished form through the coast district to the southeast and break down northward into the rolling plains and foothills of the Danube district, this foothill charac- ter is preserved through most of the northwest district adjoin- ing thereon, grading gradually into the main ranges of the Car- pathians, the divide of which forms the boundary between the Northern Districts of Austria and Hungary. The coniferous species in Austria cover over 60 per cent of the total forest area; 21 per cent are hardwoods; the balance of 19 per cent are mixed stands. Spruce predominates with 44 per cent of the total forest area, it occurs at almost all eleva- tions from the plains up to timber line, only in Dalmatia is it lacking. Scotch pine is next, with 7 per cent of the total for- est area, chiefly occurring on the plains. The remainder of the 60 per cent of coniferous stands are mixtures of various species — fir, Austrian and other pines, and larch. Of the hardwood stands which cover 21 per cent of the total forest area, beech leads the list with 10 per cent, the remaining 11 per cent are stands of oak with beech, or hornbeam with beech, or of aspen, alder, birch, etc. THE THEORY AND PRACTICE OF WORKING PLANS 179 The 19 per cent of mixed stands are admixtures of larch, Pinus Cembra ("Zirbe"), ash, elm, maple, chestnut, etc Austria shows within its boundaries the greatest variety of forest conditions.* All phases of vegetation are encountered from the semi-tropical shores of the Adriatic grading through the sandy and often rocky coastal plains, through the mount- ing foothills to the dolomitic or archaic fastnesses of the Alps and Carpathians, where all tree growth is dwarfed and even the lower stands are constantly threatened with rock slides and avalanches. The forest products vary accordingly from the finest timbers with high rotations down to mere fuel woods with the shortest of coppice rotations. Similarly, some forests are in immediate proximity to dense centres of population — as, e.g., the Wienerwald just outside the gates of Vienna — permitting almost perfect utilization because of a voracious market; some forests, on the other hand, are still virgin and as yet out of profitable reach of the lumberman's axe. Gradually, though, the increasing prices of timber' are making accessible at a profit even the stands most remote from centres of population, and soon there will be no virgin forests in Austria.f Again, the task of forest management is, sometimes, as in Salzburg, burdened by servitudes; elsewhere no such restric- tions exist. As a result the market varies greatly, but in gen- eral it is developing rapidly, especially in the export trade to Germany and Italy and other European or Oriental coun- tries. Eighty-five per cent of the Austrian timberlands are managed as high forest, of which one-third is selection forest * See "Methods of Natural Regeneration in Austria" and "Methods of Artificial Regeneration in Austria," Articles VIII and IX, respectively, in the series: " American Aspects of European Forestry," "F. Q.," Volume XI. f The Austrian government now constructs its own logging devices, saw- mills, railroads, chutes, flumes, etc.; these are used by the purchaser of the stumpage for which use he pays a proportionately higher stumpage price. Formerly stumpage was sold as in America, and the purchaser put in his own improvements; as rapidly as possible these improvements were then bought up by the government and paid in cash or in timber. 180 THE THEORY AND PRACTICE OF WORKING PLANS mostly in the "high" protection zone of the Alps; 12 per cent are managed as coppice ; 3 per cent as coppice with standards. Forest organization in Austria has reached a remarkable state of perfection despite the exceedingly irregular conditions as portrayed. The Austrian Kameraltaxe (Austrian formula — see Method No. 5, Part One, Chapter II, Section 1) dates from 1788; in the Tirol a volume period method was in use in the sixteenth century. From these early beginnings a systematic forest organization has been built up and extended even to. the most remote regions,* comprising not only the State forests but also the large tracts privately owned. Practically half of the forested area of Austria is under working plans. The salient features of Austrian working plans as contained in the government code of 1901 f are as follows: Division of Area begins with the setting aside of protection forest wherever necessary; it is usually divided from the lower * For example, the remote Bukowina, lying between Russia and Rou- mania on the extreme eastern border of Austria, shows 73 per cent of its 1,113,970 acres of forest covered by detailed working plans in perfect opera- tion. When this province was acquired by Austria in 1775 from Turkey it was largely — nearly 50 per cent of the total area — in trackless virgin forest. The first work of forest organization, that of making provisional working plans, was completed in 1818. About 1850 the preparation of final working plans was begun on the basis of period area method; failing of systematic revisions these soon became mere waste paper, the more so since it was impossible, for lack of markets and of logging facilities, to carry out the cuttings as planned. In 1875 a thorough reorganization of the forest administration in the Buko- wina was begun looking to the opening up of the hitherto inaccessible timber resources. A section of forest organization (Einrichtungsabteilung) was created in the Bukowina district similar to that already existing in all the other district offices of the empire. A thorough reconnaissance (Durch- forschung) was made and on this basis new provisional working plans prepared, beginning, of course, with the more accessible forests. As the data and utilization warranted it, these were transformed into regular plans with frequent revisions, on the model of those prescribed for the rest of Austria, with emphasis on regulation by area rather than by volume, as befits the more extensive conditions. t "Instruktion fur die Begrenzung, Vermessung und Betriebseinrichtung der Oesterreichischen Staats und Fondsforste," 3d edition, 1901. THE THEORY AND PRACTICE OF WORKING PLANS 181 slopes by a trail following the appropriate contour. This pro- tection belt is always managed as strctest selection forest The management for the rest of the area is then decided upon and the area divided according to working figures (Betriebsklassen), cutting series, compartments, and subcompartments. An area with a uniform, silvicultural system and rotation, uniform market and constituting a single logging unit is called a Betriebsklasse; it is further divided into cutting series, whose formation depends on the topography, the species, and the method of regeneration. A single cutting series does not usually comprise more than three compartments. The boundaries of the cutting series are topographic or artificial — roads, compart- ment lines, etc. These boundaries are to be cleared of timber to a width of from 16 to 26 feet, in order that a wind resisting forest mantle may form along the edges of the stands. Cutting series are shown on the maps by arrows. The compartments (Abteilungen) are units of convenience; their shape is quadrangular, 2,600 to 3,300 feet long and about two-thirds as wide. The boundary lines are topographic, cul- tural (roads, railroads, etc.), or else artificial. The last are either "Schneisen" and are usually made 6^ feet wide (2 metres), or are "Wirtschafts Streifen," with the regular width of 16 to 26 feet (5-8 metres). (See Part One, Chapter I, Section 2, "Di- vision of Area.") The division into subcompartments (Unterabteilungen) is based (1) on differences in required treatment of which the fol- lowing are distinguished: High forest with clear cutting; high forest with shelterwood cutting; high forest with selection cut- ting; straight coppice; coppice with standards; forest burdened with servitudes; protection forest, voluntary or enforced by law: or (2) on differences in species if the stands are pure: or (3) on substantial differences in percentage of mixture if the stands are mixed: or (4) on differences in average age exceeding 10 years in young, 20 years in old high forest, 5 years in coppice forest: or (5) on marked differences in site quality or yield quality as shown by substantial differences in the height growth 182 THE THEORY AND PRACTICE OF WORKING PLANS of equal-aged stands : or (6) on marked differences in the density of stand: or (7) on need of artificial regeneration. The minimum size of a subcompartment is 1^2 acres. The boundaries are marked with stencilled numbers painted in oil paint on the corner trees or else by means of symbols made with a bark scratcher; in young stands narrow alleys are cleared. Estimates and Forest Description. — As a general rule yield tables are constructed for the various silvicultural systems of management, species, and site classes, based on sample areas measured during the progress of the field-work. The following form is used: Column 1. Age. " 2. Number of stems per hectare. " 3. Basal area at 1.3 M. above ground, in square metres. " 4. Average diameter at 1.3 M. above ground, in centimetres. " 5. Average height in metres. " 6. Average annual height increment in metres. " 7. Volume by timber classes, in cubic metres. " 8. Increment — current annual, in cubic metres. " 9. Increment — mean annual, in cubic metres. " 10. Increment per cent — mean annual. These yield tables are compared with the published yield tables of the International Association of Forest Experiment Stations. The description of the individual stand covers the following phases: (1) Soil and site. (2) Species, percentage of mixture and general form of the stand. The percentage of mixture is expressed in tenths accord- ing to the area occupied by each species. Shelterwood cuttings are considered as preparatory if .8 of the original volume re- mains; as seed cuttings if .5 to .8 remains; as removal cuttings if less than .5 remains. THE THEORY AND PRACTICE OF WORKING PLANS 183 (3) Both the average age and the age limits are given. The table of age-class distribution takes the following form: Column 1. Compartment number. " 2. Subcompartment letter. " 3. Site and stand quality. " 4. Barrens and blanks. " 5.^1 stands 1-20 { partly stocked 6. ) years old ( fully stocked " 7. II stands 21-40 years old " 8. Ill stands 41-60 years old " 9. IV stands 61-80 years old ^ in hectares. " 10. V stands 81-100 years old " 11. VI stands 101-120 years old " 12. VII stands over 120 years old " 13. Total area " 4. ( Area in \ of the areas under regeneration. " 15. \ hectares ( of the areas under selection system. " 16. Remarks. A separate age-class table is prepared for each working figure ("Betriebsklasse," see above). Areas in process of regeneration are entered in full in Column 14. But, if the cutting is shelterwood the proper proportions of the areas appear also in the age class (Columns 4-12) so as to show the existing proportion of old timber, young growth, and blanks. Below the actual area of each age class, the normal area thereof is entered for purposes of comparison. (4) As index to the yield the following factors are entered: (a) The average height of the stand. (b) The sum of the basal areas. (c) The site quality and species occupying it. (d) The present density in tenths of 1 .0 = fully stocked. Stands are to be considered fully stocked if the actual volume per hectare corresponds to the volume given in the yield table for the same age, site quality, species, and silvicultural system. 184 THE THEORY AND PRACTICE OF WORKING PLANS (5) The volume of those stands which are to be cut in the next two decades. (6) The mean annual increment prorated to the end of the rotation. The data on volume and increment of the younger stands is taken from yield tables; in stands approaching maturity exact measurements in the field are required. Stands of varying den- sity, and all under 5 acres in size are to be calipered completely. In very irregular stands (e.g., mixed species, all-aged, etc.) sample plots are measured to cover from 5 to 10 per cent of the total area. The volume is calculated from the calipered diameters by measuring average trees, so chosen that in height and diame- ter they represent the stand in miniature. These data are combined in a tabular forest description which takes the following form (stand table) : Column 1. Locality (corresponds to "Block," Part One,. Chapter I, Section 2). " 2. Compartment — number. " 3. Subcompartment — letter. " 4. Soil and slope. " 5. Species, per cent of mixture and general form of stand. " 6. Age of stand — years. 7. Average height of stand — metres. " 8. Total basal area — square metres. " 9. Site quality. " 10. Density of stand in decimals of 1.0. " 11. Area in hectares. " 12) TT , . . . (per hectare. ( Volume in cubic metres ) . L , " 13 ) ffor total area. " 14 I Mean annual increment prorated ( per hectare. " 15 ) to rotation age, in cubic metres \ for total area. " 16. Volume increment per cent. " 17. Quality increment per cent. " 18. Index per cent. " 19. Remarks. THE THEORY AND PRACTICE OF WORKING PLANS 185 This is supplemented by a general forest description for the entire area, covering all of the forest conditions — natural, legal, political, economic, commercial, financial, and administrative, including personnel. Determination of the Yield is for a decade in advance. The allowed cut is divided into final cuttings, thinnings, and acci- dental cuttings. The basis of regulation is the normal periodic cutting area. If the conditions are regular this is adhered to as strictly as possible. Often there are large amounts of over- mature timber, as, e.g., in the virgin forests of the Bukowina mentioned in foot-note preceding, where with a 1 20-year rotation the stands over 100 years old aggregated 116,592 hectares in- stead of the normal (based on age-class relation) of 33,221 hec- tares; an excess of 83,371 hectares.* In these overmature stands the increment merely offsets the decay and their interest yield on the investment is nil. To substitute for them young, thriftily growing stands was axiomatic but required cutting in excess of the normally allowed area. The amount of excess permissible was fixed on the following three considerations: (1) Not so great that regeneration, natural or artificial, cannot keep pace with the cutting, and so imperil the continuity of the forest; (2) not so great as to depress prices by glutting the mar- ket and thus losing all the financial advantage gained by stim- ulated increment; (3) not so great as to cause too serious dis- turbances of the sustained yield. These considerations were met by a sliding scale of area gradually approaching the normal as follows: In the I period of 20 years 1.5 the normal area can be cut (sometimes 1.6 in the first decade, 1.4 in the second decade) ; in the II period of 20 years 1 .3 of the normal area can be cut; in the III period of 20 years 1.2 of the normal can be cut, and thenceforth approximately the normal amount only is to be cut. During the decade ending 1910 the average an- nual cutting area in the Bukowina was 3,008 hectares, or approxi- mately 1.5 the normal of 2,031 hectares. *"Die Forstwirtschaft und ihre Industrien . . . im Herzogthume Bukowina," by E. Guzman, Vienna, 1901. 186 THE THEORY AND PRACTICE OF WORKING PLANS The rotation age is determined on the basis of highest net income (Forstreinertrag) unless there are cogent reasons, such as legal constraints, logging or market conditions, for keeping a higher rotation. Stands are therefore considered mature, i.e., of proper cutting age, whose index per cent has sunk below the adopted interest per cent on the investment ani whose cutting will not interfere with the proper development of the cutting series. In addition to the stands thus mature, the cuttings of the ensuing working period are to include all very open stands and stands with unsatisfactory increment whose regeneration is obviously desirable; and also such stands as must be sacrificed to the proper progress of the cutting series. The aim is, obviously, to approach a normal distribution of the age classes. The length of time required in this approach to normal is fixed tentatively. To aid in this and in the fixa- tion of the decade cutting area the results of past cuttings are reviewed, especially in their effect on the development of the proper age-class distribution; this last is shown graphically for decades past. Based on these considerations the decade cutting area is finally fixed and the volume thereon, increased by the current increment to the middle of the decade, constitutes the allowed cut for the decade. In the selection forest of the protective belt, everything is subordinated to the protective function and hence no sustained annual cut is determined, but the allowed cut merely approxi- mated from experience. Control and Revision of the working plan which is docu- mented in bound form and called an "Operat." — The following current records are kept : (i) The memoranda book (" Gedenkbuch ") wherein all changes other than those of changes resulting from the cuttings prescribed in the working plan are entered. Changes in sur- veys; in logging methods; substantial injuries to the forest by man, climate, fire, etc.; the progress of the hunt and of fishing; THE THEORY AND PRACTICE OF WORKING PLANS 187 personnel; statistics of volume yield and money returns; forest experiments, etc. It corresponds closely to the general part of the Prussian " Hauptmerkbuch " (see Section i, above). (2) The management book corresponds to the Prussian I control book, together with the specific part of the Prussian "Hauptmerkbuch." It is divided in two parts: The first gives for each subcompartment (figure of control— " Kontrollfigur ") the yield of cuttings by classes of material and area, the com- pleted sowings and plantings, and the early care of the stands. The second part contains the total annual cut of the whole forest (Wirtschaftsbezirk) compared with the estimate. (3) Index of changes in status, comparison of the total, an- nual, actual with the allowed cut in volume and area; sum- mary of accidental— i.e., unforeseen— cuttings, of plantings, of receipts and expenditures, of income, etc. Regular revisions are made in the last year of the ten-year working period; revisions may be necessary between times if unforeseen contingencies occur, such as large windfall, insect damage, change of area, etc. The most important tasks of the revision are: First, the determination of whether the provisions of the working plan just terminating were observed in every detail; whether and to what extent the departures therefrom were justified; and whether the prescriptions of the working plan proved correct, singly and collectively. Second, the cor- rection of the existing maps and estimates which may necessi- tate the collection of additional field data. Third, the prepara- tion of the working plan for the next ten years. SECTION FOUR RESUME A review of the practice of working plans in Europe shows that forest organization developed very differently in the vari- ous countries. The differences consist in the form of the work- 188 THE THEORY AND PRACTICE OF WORKING PLANS ing-plan document; in the length of the working period; in the methods of estimating, forest description, mapping; in the principles and nomenclature of the divisions of area. These differences arose primarily out of differences in the forest con- ditions to which the methods of forest organization were adapted; in part also because the various practices developed independ- ently of one another. Many of the rules and regulations for working plans remained practically unknown outside of their immediate sphere of application. Despite these differences, the various existing methods of forest organization are very similar in the essentials of working plans. For all, the most important task is recognized to be the designation of the areas which are to be regenerated. For this the character and composition of the individual stands is scru- tinized. The more unfavorable the condition of the stands is in regard to growth, density, etc., the more is their early cutting indicated. At the same time, however, all the existing methods demand that the stands are not to be considered by themselves alone, but in conjunction with the whole area of which they form a part and their treatment decided upon accordingly. In general agreement are, furthermore, the methods of determin- ing the allowed cut. At first, regulation was by volume alone, as fitted the irregular conditions encountered; as management progressed, area came to play a more and more important part in regulation. Area and volume combined are now the basis of yield regulation in all intensively managed forests. In Prussia, Austria, Saxony, and other countries, the criterion of yield is the normal periodic cutting area wherever the conditions are sufficiently regular. This area is increased or diminished ac- cording to the distribution of the age classes. The volume on the periodic cutting area constitutes the allowed periodic cut and affords, by volume regulation, a check on the sustained character of the yield.* The consequent progress of forest organization is also very * However, under fairly regular but rather extensive conditions it is. considered sufficient to regulate the cutting by area alone. THE THEORY AND PRACTICE OF WORKING PLANS 189 a 20 similar. In the formula — or a — , which represents the annual or the periodic cutting area, respectively, r, the rotation, is set as a definite figure, as indeed is necessary for the execution of a working plan during a definite working period. As a matter of fact, however, the rotation age is not a fixed quantity, when considered for a longer period of time, but a varying quantity influenced by the changing conditions of management. To recognize these conditions and to set forth clearly their in- fluence is the common task of all methods of forest organization, a task more important than the form of the working-plan docu- ment and the method of determining the yield. The rotation age, i.e., the age of physical, silvicultural, financial, or other maturity, whichever may be chosen, is dependent on all the conditions of site, silviculture, utilization, and economics, which influence the increment of the stands and the value of the timber. CHAPTER II IN AMERICA SECTION ONE EARLY BEGINNINGS Working plans are almost coincident with the beginnings of American forestry. Before the control of the national forests passed over to the Forest Service of the Department of Agri- culture in 1905, the then Bureau of Forestry, through its offer of cooperation with private owners, prepared many working plans for timber tracts in the Eastern and Southern States. Since these plans were for very irregular, extensive conditions and were generally intended for execution by laymen who had little or no conception of the purposes of forest management, it was inevitable that they exceeded the confines of mere forest organization and often consisted chiefly of elaborate forest de- scriptions and estimates, emphasizing the silvical characteris- tics of the more important species, of logging methods and rules to prevent waste. Actual calculation of the yield was con- fined to a rather crude diameter-limit method which emphasized the possible periods of return for an equal or approximately equal cut. Little or no attempt was made to distribute the cut according to the needs of the individual stands; the regu- lation was by volume alone. As working plans these were, probably, with rare exceptions, failures; for no plan can hope to live that is made from the outside without an adequate understanding of the silvicultural and economic conditions. It was a precocious attempt to make a plan on European models without the basis of exact knowl- edge which is the fruit of decades of European experience. 190 THE THEORY AND PRACTICE OF WORKING PLANS 191 The plans, as such, were valuable chiefly for the estimates, maps, and other field data which they furnished to the owner, and for the volume, growth, and other silvical data which they furnished to the Bureau, together with a splendid field training for the men concerned in the work. It is doubtful if any of the plans were ever maintained; for no adequate provisions were made for their control and revision and, though drawn up for decades in advance, they soon lapsed into desuetude. Some were published as bulletins of the Bureau, and are now chiefly valuable for the volume and growth tables, and other silvical data which they contain, and as landmarks of the progress toward an American forest management. SECTION TWO THE NEW RECONNAISSANCE On February i, 1905, the Forest . Service of the Department of Agriculture took over the charge of the then forest reserves. The tremendous task of organizing the administrative machinery over an area of over 100 million acres absorbed all the energies of the forest service, and although the need of working plans was repeatedly recognized by those in authority and a few sporadic plans were actually made,* nothing systematic was done until the winter of 1907-08, when for the first time rough esti- mates of the timber standing on the various national forests were compiled. The section of reconnaissance in the office of forest manage- ment was reorganized and its activities diverted from a study of the distribution, existing volume, utilization, and management of the more important commercial species (so called "Comraer- * For the details of this development see article "The New Reconnais- sance, Working Plans that Work," in Proceeding Soc. Am. Foresters, Volume IV., No. 1. Reprinted Yale Publishing Association, 1909. 192 THE THEORY AND PRACTICE OF WORKING PLANS cial Tree Studies") to the far more pressing task of systematiz- ing and controlling the estimates, allowed annual cut, marking rules, stumpage rates, and sale policy of the national forests which then aggregated about 175 million acres. The compilation of estimates from the various national forests were so glaringly inadequate that steps were immedi- ately taken to secure reliable estimates of all the forests, begin- ning with those where the cutting was heaviest and threatened to exceed the proper allowance. The method of estimating developed was that described above in Part One, Chapter I, Section 2, "Estimates," and, with minor changes, has continued in use to this day. This method aims to strike the mean be- tween the rough guesses of supervisor and rangers and the accurate but far too slow strip valuation surveys. By the placing of several parties in the field each season good progress has been made * towards securing fairly reliable estimates and forest descriptions and usually excellent maps. Based on these field data, insufficient though they are, sim- ple working plans have been prepared in accordance with stand- ard outlines. The outline now in effect (191 2) is as follows: I. General Description (General data which relates to two or more sections of the plan, or which can be treated more logically here than under other sections. Under most headings the discussion will be a summary of important points treated in detail in other sections of the plan.) Creation. Area, past and present. Totals of alienated lands by classes. • (Tabulated form.) Physical features. (Concise. Include the information which has a distinct bearing upon or forms the basis for the provisions of the plan.) Climate. (Data not of direct application may be placed in the Appendix.) Topography. (For use in the division of the forest into working circles, as well as its bearing upon use, development, and administration of the forest.) Geology. (As it affects soils, etc.) Soils. (In such form that statement made may be applied directly in silvicultural practice, settlement, policy, etc.) Land classification. Forest, agriculture, grazing, barren, etc. (Tabu- lated. Brief discussion, if necessary.) * See "The Progress of Reconnaissance," "Forestry Quarterly," Volume VIII., No. 4. THE THEORY AND PRACTICE OF WORKING PLANS 193 Transportation. (Railroads, water, etc., only as it affects the administra- tion or the development of the forest.) Settlement. Present and probable future. (As it affects the forest and the plan.) Industries. Mining, grazing, ranching, lumbering, etc. (Only as they have a bearing on the plan.) II. Silviculture Timber: Estimates and detailed descriptions of timber. Estimates by species, separately by divisions, blocks, and other natural or artificial sub- divisions. Quality and condition of timber, age classes if stand is even-aged, accessibility, information on logging, etc., as necessary, cut-over areas. (Tabulation.) Forest Types. Composition, occurrence, distribution of age classes, and condition of timber. (Concise general descriptions, and the funda- mental silvicultural requirements and principles which form the basis for the choice and application of silvicultural systems.) Species. (Concise. Treat, from the standpoint of the type and the stand rather than the individual tree, the characteristics and requirements upon which will be based conclusions regard- ing the species to be favored and the relation in the management of each species to the others in the stand or type.) Climatic, soil, moisture, and light requirements. Growth, form, volume, etc. (Tables to be included in the plan if they will be used frequently, otherwise in the Appendix.) Reproduction. Advance reproduction present. Conditions necessary to secure it. Value of wood. (Properties. Comparative values.) Causes of injury. Fire, insects, fungi, mistletoe, smeiter fumes, weather, animals, etc. (Control under protection.) Increment. Yield tables or other data, or the method used to deter- mine increment. Effect of thinnings on growth, etc. Timber operations. Markets. Consumption and demand, local and general, past, present, and future. Relation to surrounding forests if any. Cut, by years, sales, and free use. (For use in the determination of working circle boundaries and in regulation.) Prices. (To aid in stumpage appraisals.) Methods and utilization. (Methods in relation to preservation of proper silvicultural conditions, also as a basis for costs. Reasonable possi- bilities in utilization.) Costs. (As a basis for stumpage appraisals.) Objects of Management. Watershed protection, species of timber and classes of material, sustained annual or periodic yield, etc. (State specifically in order of importance the objects which materially affect the provisions of the plan.) Silvicultural Systems and their application. For each type. (Concise de- scriptions of the systems adopted and provisions for their specific appli- cation. Include brush disposal.) Regulation of yield: Rotation, cutting cycles, etc. (Rotation of maximum volume production. Cutting cycles as short as practical considerations will allow.) Division of the forest into necessary divisions (working circles), areas within which sustained yield, annual or periodic, is now or will ulti- mately be desirable, based upon markets, transportation, and to- 13 194 THE THEORY AND PRACTICE OF WORKING PLANS pography. (This may be done elsewhere in cases where such action will simplify treatment.) Blocks and chances only when they are actually needed to assist in regulation. (Blocks — main logging units or groups of logging units. Chances — single logging units or the subdivision of blocks necessary to carry out the management.) Annual or periodic cut. The limitation of cut including sales and free use. Accurately for ten years, and approximately for the periods of the rotation. (Include in the plan only the essential features of the method used, and cover necessary details in the Appendix. Blank table for tabulation of limitation and amounts actually cut. Sales and free use.) Sales. (By divisions, if advisable.) Policy. Restriction and encouragement and location. (The plan of cutting and specific application to actual conditions of the preceding conclusions and of the service policy and regulations. Past man- agement to be treated only as it will help in an understanding of that proposed.) Stumpage appraisals. Maximum and minimum rates. Administration and other features. Special force needed. Costs. (Summary for use in obtaining total forest expenditures in Section VII.) Free Use. (Principles applying specifically the general free use policy, espe- cially where it is more or less vague and general. By divisions, if advisable.) Present and prospective annual demand by classes of users and of forest products. Policy, restriction, or encouragement by districts and classes of products. Administration. Free use areas. Blanket or year long permits. Other measures to promote economy. Special force needed. Costs. (Summary for use in obtaining total forest expenditures in Section VII.) Map or maps showing topography, types, classification of timber, boundaries of divisions, blocks, etc., free use areas, cut-over areas, etc. Fores tation: General relation to ultimate timber management. Areas requiring forestation. By types. (Brief description. Tabulated.) Methods and species. (Concise. Base upon results of past work. In addition to sowing, planting, etc., include seed collection, poisoning rodents, etc.) Detailed plan. (Five years, or if impracticable, omit and provide for annually.) Areas, methods, and costs. (Tabulated.) Administrative features. Special force needed. (Regular and special work such as seed collecting, etc.) Nursery. Ultimate production, species, and numbers. Methods. (Essential features.) Detailed plan. (Five years.) Species, numbers, and costs. (Tabulated form.) Administrative features. Special force needed. Map showing areas to be reforested, classified as above, etc. Investigations: (Which can be conducted inexpensively in connection with the regular administration of the forest and which should result in prac- tical information needed in the administration. Brief.) THE THEORY AND PRACTICE OF WORKING PLANS 195 III. Grazing nange Management: Types. (Concise descriptions of each.) Names of important and characteristic forage plants. Accurate data on seasons of growth. Accurate data on forage value. Acreage. With forage. Waste. (Tabulated.) Carrying capacity. Present. Possible. Brief descriptions. By allotments or divisions. (Tabulated.) Demand and other local conditions in the live-stock industry which affect grazing on the forest. Relation to silviculture. Allotments. Arrangement. (Division of the range between cattle and sheep, grazing districts, and individual allotments to be shown on map. Guiding principles, or necessary comment in the discussion.) To secure Best division between cattle and sheep. Full and equal utilization. Best division of types and early and late ranges. Best division of watering places. Proper silvicultural and watershed protection. Number and kind of stock grazed. By allotments or divisions. Num- ber of permits by classes. Seasons. (To secure full utilization of the forage without seriously in- terfering with the natural requirements of plant growth, each portion of the range should occasionally, every few years, be grazed only during the last half of the natural growing period in order to keep the plant constitutions strong and allow some actual reseeding. So far as is consistent with this principle, the green tender feed should be available for the stock during as much of the season as is prac- ticable. This is essential, especially for sheep. This plan may be considered a variation of seasons or a division of allotment.) Fees. By classes of stock and season. (Tabulated.) Methods of handling stock. Cattle. _ (Salting and necessary riding by permittees to secure equal utilization of range and prevent congregation along streams and water holes, with resulting destruction of plant growth and poor development of stock.) Sheep. Size of bands. Herding. (Develop open quiet herding and avoid driving back to camp.) Salting. (Encourage abundant use of salt, it means easier herding, less danger from poison and disease, and less damage to the range.) Other stock. (When special provisions are required.) Range improvements: (Permanent improvements in the improvement section.) Reseeding either with cultivated plants or by restricting grazing for natural reseeding, posting poisonous areas, changes or improvement in stock driveways, extermination of predatory animals, prevention _ of erosion by proper handling of stock. Policy and administration. General principles of policy not already covered. Protective and maximum limits, new owners, advisory boards, etc. Administration. Extermination of predatory animals, counting stock, or other special phases of the work. Special force re- quired. Costs. (Summary for use in obtaining total of forest expenditures in Section VII.) 196 THE THEORY AND PRACTICE OF WORKING PLANS Investigations: Proper seasons, carrying capacity, poisonous plants, artificial reseeding, demonstration tests of proper utilization, effect of grazing upon reproduction, and most efficient systems of grazing management to eliminate damage. Herbarium with necessary notes. Map or maps, showing types, water, fences, corrals, topography, grazing dis- tricts, allotments, reserved areas, driveways, or other factors or features which influence or illustrate the handling of the stock. IV. Lands Settlement: Soils. (Classification with brief description and a statement of compara- tive agricultural and forest value of each class based upon land values, forest expectation values, etc.) Demand for agricultural lands. Past, present, and future. Policy. (In I, 2, and 3 order, application of policy based upon the pre- ceding classification, results of past policy, service policy, and any other principles as a guide to examiners. Practicability of detailed classification of certain districts in advance of application.) Map, showing soil classification, if data is available. Uses and Easements: Resources. Demand. Past, present, and future. Policy. (Special features which are important by kinds of uses or ease- ments. Include charges compared with value to users.) Water-power: Resources. Streams, sites, power. Cost and market data and stream measurements. (Tabulate.) Demand. Past, present, and future. Policy. (Special features.) A dministrative sites: Sites, rights of way, etc., withdrawn, or still needed and to be withdrawn. Include comprehensive plan of rights of way needed for future sales and other uses as well as sites and rights of way required in admin- istration. (Tabulate or show on map.) A dministration : Special force needed. Other administrative questions. Costs. (Summary for use in obtaining total forest expenditures in Section VII.) Investigation: Map or maps showing status, location of uses, easements, water-power pro- jects, administrative sites, etc. V. Protection Fire: (By divisions or geographical subdivisions, if advisable.) Liability. Statement of value of destructible resources by classes, and for districts or regions. Timber, expectation value of young growth, forage. Arbitrary value per acre of watershed protection. (Possible money damage. Tabulate.) Hazard or risk. Statement by types or regions based upon character of stand, danger of fires starting, and difficulty and cost of suppression. (Should be based in part upon a study of past experience.) Protection required. (Principles which sum up on the basis of liability and hazard the relative amount of protection needed in specified parts of the forest.) THE THEORY AND PRACTICE OF WORKING PLANS 197 Control Improvements available. By districts. (Brief description, tabulate if map is not sufficient.) Communication. Telephone, etc. Transportation. Railroads, roads, trails, pack -trains, etc. Fire lines. Look-out stations. . - Supplies and tools. (Distribution or how they are to be purchased, etc. Tabulate.) Cooperation. ... r- • *.- Adjoining forests, between ranger districts, State associations, cor- porations, individuals, etc. Organization and administration. For look-out stations and patrol. Numbers of men and duties by districts. (Tabulate so far as possible.) For fighting fires. (Tabulate if possible.) Regular and temporary force. Cooperation, labor, including users. Outside labor. . Costs. (Summary for use in obtaining total of forest expenditures in Section VII.) , Specific and detailed instructions to rangers based on the above, and resulting in its direct application should be issued to all forest om- cers engaged in fire protection. Map showing types, topography, improvements, and as much oi above information as is possible and advisable. Copies to accompany letters of instruction. Insects: Extent of infestation and damage. . Control, administrative measures, methods. Special force needed. Costs. (Summary for use in obtaining total of forest expenditures in Section VII.) Other damages: Extent. Amount of damages. Control, administrative measures. (As under Insects.) Game: Policy and administrative measures. Investigations: VI. Improvements Improvements. Comprehensive plan of the improvements needed. Loca- tion, brief description, estimated costs, indicate those which should be undertaken within the next five years. (Tabulated form.) Roads, trails, telephone lines; fire lines, administrative fences, stock fences, including the fencing of poisonous areas and bog holes, bridges, corrals, dwellings, other buildings, water development, steam improvement, dams to prevent erosion, other projects. Maintenance, as above. Policy and administration. Improvement policy of the forest. (Concisely by lines of work such as silviculture, grazing, protection, general administration, etc.) _ Administrative provisions. Special force needed. Costs, exclusive of the costs of individual projects. Map showing all improvements constructed and planned, with a sufficient amount of other data to make intelligible. 198 THE THEORY AND PRACTICE OF WORKING PLANS VII. Administration Administrative districts. Number, area, and relative importance or amount of work. (Tabulate.) Force. Office and field and assignment. Salaries. Also a brief forecast of future requirements. (Tabulate.) . Permanent, statutory. Semi-permanent and temporary. General administrative policy of forest. (General relation of important lines of work. Include also points not already covered; fully and briefly in i, 2, and 3 order.) Receipts and expenditures and results. By lines of work for fiscal years, past and estimated future. Administrative provisions for increasing receipts or reducing expendi- tures. Map, boundaries of administrative, or other districts. Appendix Material which should be preserved in connection with the plan, but which will be used infrequently in actual forest administration. List of species. Details of methods used in the collection of data, costs, and areas covered. (Reconnaissance.) Tables, growth, volume, etc., when it is reasonably certain that they will be used infrequently. Details of method for regulating yield. Detailed silvical discussions upon which conclusions and principles outlined in the plan are based, if preservation seems necessary or advisable. General notes upon which the conclusions in the plan were based. Inventory of existing improvements, if desired. (Tabulate.) The first attempts to determine the allowed annual cut for each national forest, necessarily in advance, often, of any regu- lar working plan, were very crude. Nevertheless, though based on insufficient data, the attempt recognized the fundamental principle of a sustained yield. For each national forest the annual yield has been fixed since 1908. At first this was taken, roughly, as equal to the current annual increment, a crude calculation based on often faulty estimates and insufficient growth data, but giving at least a working basis. The allowed cut so calculated was not distributed on the ground, since this would have been a useless play, but instead a definite sale policy was drawn up for each forest by dividing the forest into areas where ordinary sales, i.e., of large size, are desirable, areas where small sales (for local industries) only are THE THEORY AND PRACTICE OF WORKING PLANS 199 desirable, areas for free use of inhabitants only, and areas re- served as protection forest. This rough division of area, indicated on forest and district maps, was further supplemented by general notes on areas re- quiring cutting because of overmaturity, insect damage, dis- ease, fire, and the like. Minimum stumpage rates for each species and class of ma- terial were also fixed for each national forest so as to prevent the wide variation in prices obtained. It had been the custom to draw up special marking rules for each timber sale of larger size. To avoid constant repetition these began to be combined into a set of marking rules for all the various forest types contained within a certain national forest and these rules made standard for all sales within that forest. These rules by forests were then combined into general marking rules for the various silvical regions of the West. This work was completed in November, 1908, and the mimeographed marking rules as sent out to all forest officers represented the best information then available on the very important question of marking trees -for cutting in timber sales. They have been revised from time to time and have been aptly supplemented by actual examples of properly marked areas as an ocular de- monstration of how to do it. Although the section of reconnaissance had brought to- gether all the data stored in the files of the service and built thereon the first crude beginnings of a systematic forest organ- ization, further progress would have been impossible except for the active cooperation of the men in the field. Realizing the inadequacy of the existing estimates and the time which must elapse before each forest could be covered by detailed recon- naissance, a circular letter was sent to all the supervisors in the spring of 1908 requesting them to make every effort to correct and amend existing estimates during the approaching field season and to segregate the estimates by blocks (i.e., by watersheds), by species, and by classes of material. 200 THE THEORY AND PRACTICE OF WORKING PLANS A similar letter was sent asking the supervisors to draw up, each for his forest, a plan of sale policy, indicating those areas on which cutting should be restricted or encouraged according to economic and silvicultural conditions, etc. The first crude regulations of the yield (allowed annual cut), sale policy, and minimum stumpage rates were also sent to each of the six inspection districts and the chief inspector requested to revise and amplify them according to his local information. In the Southwestern district (No. 3) Acting Chief Inspector Woolsey availed himself of this splendid opportunity to draw up a complete, far-sighted limitation of cut and sale policy for each forest and for the district and also minimum stumpage rates by forests, species, and classes of material. His sale policy was by far the most complete of any prepared, the more so as he proceeded to determine the allowed annual cut for each forest, separately for saw timber and cord-wood, by Von Man- tel's Method (see Part One, Chapter II, Section 1, Method No. 2). Crude as this method is, it was a marked step in advance and the regulation of yield on the national forests has only in the last year or so advanced from Von Mantel's "beautiful sim- plicity" to some of the higher methods, such as the Austrian formula, Heyer's formula, and the like (see Part One, Chapter II, Section 1). When the six Western administrative districts were created in December, 1908, the office of management, and with it the section of reconnaissance, ceased to exist. So enormous had been the undertaken task of systematizing and controlling the estimates, allowed annual cut, marking rules, stumpage rates, and sale policy that only the foundations of a correct forest organization were turned over to the districts whereon to build. The office of silviculture in each of the districts took over the task and the manual of procedure in the district offices provided for annual revisions of the estimates, sale policy, allowed annual cut, minimum (later standard) stumpage rates, and marking rules, to be submitted by the supervisors, combined by the district forester and in the case of the allowed annual THE THEORY AND PRACTICE OF WORKING PLANS 201 cut, forwarded by him to Washington for review by the forester and approval by the secretary. The limitation of annual cut as fixed by the secretary — based, of course, on reasons of sale policy — could not be exceeded without his consent. However, this was seldom required; for inaccessibility and competitio* with private timber restricted the bare possibility of national forest sales to a point far below what the forests would support. Thus in 191 1 the amiual cut which the national forests were estimated to be able to sustain permanently, totalled 3,274,- 000,000 board feet. The actual cut under both timber sales and free use permits was 498,000,000 board feet, but little over 15 per cent of the actual yield of the forests. SECTION THREE PRESENT PROCEDURE The decentralization of working-plans control resulted in a most unequal progress in forest organization. Starting with the same foundations in December, 1908, there were, in matters of working plans, much confusion and wasted effort. This un- fortunate condition was relieved by the issuance, late in 191 1, of the forest plans section of "The National Forest Manual " * which restores system and purpose to the work of forest organiza- tion and is a big step in advance towards unifying the working- plan procedure of the various districts. The essentials of the manual are given below, together with its proposed application in the Southwestern district. It is significant to note that the manual calls for preliminary plans to be prepared immediately, to be followed, as data warrant, by a regular working plan. This continues the work begun by the * "The National Forest Manual: Instructions to forest officers, relating to forest plans, forest extension, forest investigations, libraries, cooperation, and dendrology. Issued by the Secretary of x^griculture to take effect November I, 1911." Washington, Government Printing Office, 1911. 202 THE THEORY AND PRACTICE OF WORKING PLANS former section of reconnaissance and emphasizes the fact that "the completion of any plan is but the beginning of systematic management." There follows, in somewhat condensed form, the Forest plans portion of The National Forest Manual: FOREST PLANS The object of the forest plan is to systematize and control the management of each forest upon a definite basis which shall represent the cumulative experience and information which the service has acquired. Three different kinds of plans, differing only in scope and intensity, will be used in developing the management of the respective forests, namely, preliminary plans, working plans, and annual plans. A preliminary plan is simply a systematic statement, pre- pared from the best information now available, of the resources of the forest, the conditions governing their use and develop- ment, and the administrative measures to be followed in their management. A working plan is a similar statement, more complete and final in character, based upon thorough investigation and accu- rate data, and including a definite scheme of management devised for a period of years. The annual plan is covered by the various periodic estimates and reports. It constitutes a periodic revision of the prelim- inary or working plan, together with the specific application of these plans to the business of the forest for the ensuing year. The subjects to be covered in all forest plans are: i. General administration. 2. Silvicultural management. 3. Grazing management. 4. Permanent improvements. 5. Forest protection. 6. Uses of forest land. THE THEORY AND PRACTICE OF WORKING PLANS 203 Each forest plan will provide for the management of a whole administrative unit or forest. No plan should include more than one forest. Where conditions in adjacent forests are sim- ilar, or the forests supply the same markets, these facts will be considered, particularly in the location of cutting area and limi- tation of the annual cut. Such considerations will also be necessary in grazing and protection. Where necessary, because of important market or topo- graphic considerations, the forest may be divided into areas, each of which will be managed with the idea of sustained yield. If necessary to assist in regulating the cut, a subdivision of the above areas may be made; this should be on the basis of logging units or groups of logging units, the boundaries depending entirely upon topography. Unnecessary divisions will not be made, since they complicate administration. Where possible the lines of administrative subdivisions and those for the technical man- agement of the forest will be coordinated. Final responsibility in the preparation of all forest plans rests with the supervisor. He should, in submitting the plan for approval, transmit any recommendations of the officer in direct charge of its preparation which differ materially from the plan as submitted. Since the completion of any plan is but the beginning of sys- tematic management, every effort should be made to improve plans which have been prepared and to obtain the additional data needed for more efficient administration. PRELIMINARY PLANS A preb'minary plan should be prepared as soon as practicable on each forest from the data now available. The compilation of such data in the form of a definite plan of management will systematize and strengthen the administration of the forest and furnish a basis for further extension and improvement. The following points should be covered: Under "General Administration" should be given: i. The forest force, based upon the men required to transact 204 THE THEORY AND PRACTICE OF WORKING PLANS economically the business of the forest and furnish adequate protection during the fire season. 2. Division of the forest into administrative and patrol dis- tricts to be shown on a map. 3. A record by classes of past receipts and expenditures and an estimate of future receipts and expenditures. Under " SilvicuUural management" should be given: 1. Divisions and subdivisions, if any, with reasons. 2. Approximate estimates of timber by convenient, tech- nical, administrative, or legal subdivisions. 3. The silvicultural systems which should be used, by types, and by divisions if modification of the system on different divi- sions is necessary. Principles to govern marking drawn from the best silvical data available. The object of management for the forest, as far as available information makes it possible, or for divisions, classes of material to be produced, species to be favored, and rotation desirable. 4. A rough classification of the timber on the forest, or parts of the forest, in accordance with its age and condition, showing the bodies of mature timber, of thrifty timber not yet in need of cutting, and of young growth; together with a plan of cutting, showing the order in which the various areas should be logged. Areas of protection forest where no cutting is recommended should be indicated. The approximate periods in which imma- ture stands will reach merchantable size should be shown. 5. Recommended limitations on the annual cut* for the ensuing four or five years. 6. Data on methods of logging, accessibility of merchantable bodies of timber, costs of logging and manufacture, markets and market conditions, demand, prices, etc. 7. The policy for the whole forest, or divisions if advisable, which should be followed as to sales, reservations for local in- dustries, and free use, together with the opportunities for de- sirable sales. * I.e., determination of the yield — see Part One, Chapter II, Section I. THE THEORY AND PRACTICE OF WORKING PLANS 205 8. Tentative stumpage rates for the entire forest, or divisions. 9. Improvements needed to facilitate the sale or protection of timber. (To be incorporated in the permanent improvement plan.) 10. The approximate areas on which artificial reforestation will be necessary in whole or in part, together with the species to be used, and, broadly, the plan to be followed during the ensuing four or five years, plans for nurseries, outline of desir- able experiments, etc. 11. The order in which the various parts of the forest should be covered by complete reconnaissance,* desirable silvical studies leading toward better management, etc. This part of the plan should be accompanied by a map show- ing topography in as much detail as data available will allow, roads, trails, forest types, age classes, if necessary, nursery sites, and areas proposed for artificial regeneration. Much of the other data called for may be shown either on the map or in con- cise tabulations with explanatory notes. Under "Grazing" the essential point is to compile all avail- able information on the range conditions in the forest as a basis for systematic range protection, development, and improve- ment. The following outline is intended only as a guide: 1. Classification of grazing lands and estimates of carrying capacity, including: (1) Determination of characteristic ecological types or groups of forage plants, each of which includes certain combinations of grasses, weeds, and browse. The types should be mapped on a base map of the forest. Groups containing poisonous plants may demand particular attention. (2) Concise descriptions of each group or type including notes on individual species, the seasons when the plants may be used, the relative grazing value of the types, and the class of stock for which they are best suited. (3) A record in tabulated form of the kind and amount * I.e., estimates as described, Part One, Chapter I, Section 2. 206 THE THEORY AND PRACTICE OF WORKING PLANS of stock at present grazed on the land, with an estimate of its present grazing capacity, and if overgrazed or poorly stocked with forage plants the capacity to which it may be brought by proper treatment. 2. Range improvements: Map record of present and needed watering facilities, including wells, streams, springs, natural and artificial ponds and tanks, drift fences, and other improvements necessary for the best use of the range. (To be incorporated in the permanent improvement plan.) 3. The plan of management should include, with necessary maps, notes, and explanatory data, provision for: (1) The control and eradication of poisonous plants. (2) Improvement of overgrazed or poorly stocked areas, including reseeding, the use of a rotation scheme of excluding stock from areas for a part of the year to allow seeding of native plants, etc. (3) Fuller use of the range by the class of stock for which it is best suited, including areas not now used. (4) Exclusion or reduction of stock or the change of grazing seasons when necessary for silvical reasons or the protection of watersheds for irrigation or municipal water-supply. Reduc- tion to prevent overgrazing, or erosion caused by grazing. (5) The better handling of stock, including salting, bedding, the prevention of concentration to the injury of the range, im- proved herding methods, etc. (6) Improvement in range districts, range allotments, etc. (7) The extermination of predatory animals, based upon the kind and amount of damage done. (8) The extermination of prairie dogs, based upon the area occupied and the damage done. A systematic plan for the Permanent Improvements on the forest should be steadily developed, extended, and improved. The improvement plan will take the form of a map, and such additional notes as may be necessary for its proper understand- ing. Rough estimates of cost should be included wherever obtainable. The following kinds of work will be considered: THE THEORY AND PRACTICE OF WORKING PLANS 207 Roads, trails, bridges, telephone lines, signal systems, perma- nent and temporary headquarters, pastures, look-out towers, fire lines, tool boxes, improvements necessary for range develop- ment or making timber accessible, and areas in which the blazing and posting of trails is urgent. Under "Forest protection" provision will be made for pro- tection against fire and insects, and the protection of nurseries and plantations against rodents. A plan for fire protection, as complete as is now practicable, should be formulated and put into effect on each forest. The fire plan will consist of a map showing detailed topog- raphy, forest types, all permanent improvements which will be of any value in fire protection, look-out points, lines of fire patrol, camping sites, places where assistance in fighting fire may be obtained, areas of particular menace and areas in particular need of protection, and detailed directions to rangers con- cerning fire patrol, and cooperation with other districts and forests. Under "Uses of Forest Lands" data should be collected showing: i . Sale prices of agricultural lands within or near the forest, including stump lands, unimproved non-timbered lands, and improved ranches. 2. Cost of clearing and stumping timbered lands 3. Comparative value of timbered land for agricultural and forest purposes. The location of all uses which have been granted should be recorded on a base map of the forest. Any information secured as to tracts desirable for particular uses should be similarly recorded, especially reservoir and dam sites, as part of the in- ventory of the resources of the forest. The water-power possibilities of the forests, including stream measurements and the collection of cost and market data. All administrative sites should be shown on the improve- ment map of the forest. Sufficient additional data will be re- corded to show in concrete form the system of administrative 208 THE THEORY AND PRACTICE OF WORKING PLANS sites devised for the forest, including patrol and look-out sta- tions, nurseries, and sites required for logging facilities, and other uses in connection with the sale of timber. WORKING PLANS A working plan is simply an extension and development of the preliminary plan, based upon more exact data. Such a plan should ultimately be prepared for every forest as the need for a more systematic basis of management becomes urgent. Re- connaissance work should, except in unusual cases, result in working plans. Working plans will be prepared first on forests where the demand for timber is great as compared with the supply, and where large quantities of timber are evidently mature and it is reasonably certain that sales can be made if the proper data are secured. It may be advisable to prepare special working plans for forests on which large areas are in need of reforesta- tion. Special grazing working plans may be prepared for forests where the use of forage resources is of importance. Special problems in any other phase of service work demanding careful study may require the preparation of working plans. Where conditions on a forest differ widely, it may be advisable to cover only the part of a forest to which the special administrative urgency applies. Each working plan will outline the general management of the forest for a long period, usually a rotation in the recommen- dations on timber cuttings, and the management in detail for some such period as 10 or 15 years. The amount of detail in the working plan will depend upon the value of the forest products concerned, the need for inten- sive methods, and the certainty or possibility of large returns within the probable life of the plan. On forests or parts of forests where the demand for timber equals or exceeds the amount which can be cut with safety, the plan for silvicultural management must be in much greater detail than where the demand is comparatively small. The requirements of detail in > THE THEORY AND PRACTICE OF WORKING PLANS 209 'the different parts of the plan and in different working units must be adjusted to the administrative needs of the forest in all lines of work. When it has been decided to make a working plan, its essen- tial features and the field-work necessary should be outlined at a conference between the officer who will have charge of the field-work, the supervisor of the forest, the assistant district foresters concerned, and the district forester at his discretion. It is particularly necessary that the general system or systems of management be determined, and the methods for determin- ing the yield of each unit be decided upon. Plans may then be made to secure the exact data needed and unnecessary work eliminated. The preliminary plan for the forest and working plans already prepared will form the basis for this discussion. Field data will in general be obtained by special* parties, which as far as possible should consist of experienced men. As far as possible, the data for all parts of the plan will be collected at the same time, if necessary by specialists temporarily assigned to the party. The data for planting or grazing features may be collected independently when the need justifies it. The work will be done under the direction of the supervisor. As far as possible all data in the working-plan report will be tabulated with brief notes of necessary explanation. While working plans must be complete, every possible effort will be made to eliminate unnecessary discussion and to put them in concise form. All detailed data relating to climate, geology, soil, growth studies, silvical notes, etc., should be placed in the appendix of the working plan, and everything in the plan sub- ordinated to the actual scheme of management for the forest. Working plans will be approved by the forester. The general ground to be covered by working plans is as follows: Under "General Administration''' the topics listed for pre- liminary plans should be discussed with such further detail as more intensive study makes possible. Under " Sihicultural management" the topics listed for pre- 14 210 THE THEORY AND PRACTICE OF WORKING PLANS liminary plans should be developed with much greater accuracy and in much greater detail. To secure uniform data from the national forests in each district, the district forester will decide upon standard field methods. Standardization will include : i. Methods of making estimates under specified conditions to secure results of uniform accuracy. 2. The unit for recording estimates in both surveyed and unsurveyed ground. 3. The minimum sizes to which timber will be estimated and a method of classifying reproduction and young timber below this minimum. 4. A scale for field and base maps and the conditions under which contour or hachure maps will be made. 5. The form and character of notes on silvicultural ques- tions, forest descriptions, etc. 6. The principles upon which the silvicultural system, the rotation, the period for which management will be planned in detail, etc. In each district, also, to insure reasonable uniformity under similar conditions, a careful study will be made of the methods of determining the limitation of annual cut under each silvi- cultural system which will be used, and standard methods established. In the completed plan the data secured under each topic will be summarized and the conclusions stated. The following points are of special importance : 1. Silvicultural systems based on the most reliable silvical data available, and upon careful observations on the part of the working-plans officer (i.e., the forest organizer). 2. A carefully drawn set of marking principles (marking rules) designed to put into effect the silvicultural systems rec- ommended. 3. The maximum annual cut to be allowed during the ensu- ing 10 or 15 years, and the approximate cuts for each period of the rotation. THE THEORY AND PRACTICE OF WORKING PLANS 211 4. The order in which the important bodies of merchantable timber should be sold. 5. The order in which areas needing artificial restocking should be sowed or planted, and the acreage to be covered dur- ing each year of the period for which detailed recommendations are made. Under "Grazing," technical reconnaissance and special studies should be conducted, following the general ground covered under preliminary plans, but with more detail and greater exactness; it should be directed as far as practicable by grazing experts. The permanent improvement plan, protection plan, and plan for uses of forest land for the forest should be considered and developed as far as may be practicable in connection with the intensive timber estimates and other investigations conducted by working-plan parties. ANNUAL PLANS The annual reports, estimates, and recommendations sub- mitted on the various lines of forest work should be based upon the preliminary or working plan for the forest and should refer specifically to the portions of the plan dealing with the subject in question. They should show how far it is feasible to apply the plan to the work of the forest during the current or ensuing year, the specific action proposed to put its provisions into effect, and the changes which appear advisable. Annual recommendations on maximum and minimum stump- age prices and limitation of yearly cut should be submitted to the district forester. These and the planting and nursery reports should refer to the portion of the plan dealing with sil- vicultural management and indicate any necessary changes in its application. Revisions of the cutting methods advocated in the plan and of other features of its silvicultural management should be submitted whenever they appear advisable, together with any additional data secured on estimates, logging costs, market conditions, etc. 212 THE THEORY AND PRACTICE OF WORKING PLANS The annual grazing report and recommendations constitute a concise restatement of the preliminary or working plan and its application to the business of the ensuing year. Additional data should be reported and necessary changes from the plan noted. In submitting the annual improvement estimates a copy of the improvement map of the forest, showing the plan as revised and extended to date and indicating the work of greatest urgency, should be furnished. In connection with the annual fire report, the fire plan for the forest should be checked over and necessary modifications noted. The annual planting and nursery reports should in- clude a current revision and application of the portions of the protection plan dealing with rodents. Special reports and revi- sions of the forest plan as regards protection from insects and diseases will be submitted from time to time on forests where this work is of importance. In connection with the current business and periodical re- ports relating to uses of forest land, the preliminary or working plan should be steadily revised and extended. The application of the foregoing instructions has been worked out by each of the districts. The proposed outline for the plan of silvicultural management, as worked out in the Southwestern district, follows. This outline is in skeleton form, so as to give an idea of the bulk and character of the plan in its final form. It is to be used in the preparation of both preliminary and final working plans. When all, or the majority, of the chapters have been completed in satisfactory final form, the plan will be submitted to the forester for approval as a forest working plan. The outline follows the instructions of the manual (see above) that a plan should consist just so far as possible of tables and maps. Most of the tables provide for the entry of records in future years. A two-inch margin will be left at the right of all text throughout the plan for the purpose of allowing notes to be made from time to time. Tables will, however, extend the width of the page. THE THEORY AND PRACTICE OF WORKING PLANS 213 The entire plan for each forest is to be bound in a cover and will contain only the strictly necessary information; all sup- plementary or basic data will be filed in a separate file for forest plans. The forest plan thus bound will serve as a hand-book of the forest. Two copies are prepared: one for the super- visor's office; the other for the district forester. It is aimed to keep the plans up to date by penned notes in the blank spaces which may, as a rule, simply refer to correspondence or reports which alter the plan or supplement it. Every few years the plan may be typewritten and all of these changes incorporated in the text or tables. OUTLINE FOR PLAN OF SILVICULTURAL MANAGEMENT TIMBER ESTIMATES BY DIVISIONS Division Sawtimber (M. ft. B. M.) Cordwood (Cords) • Notes. — Explain above divisions. Make reference to township or section sheets if available. Tabulate estimates by natural divisions, technical division (or compartment), Ranger districts, or watersheds, according to data available and with view to homogeneous units of management. 214 THE THEORY AND PRACTICE OF WORKING PLANS TIMBER ESTIMATE IN DETAIL Division * Block f Township Species Total... . ' * Handle subjects under Silvicultural Management for each division in greater or less detail according to data available for each. A division which is a distinct unit and for which a sustained yield is desirable, independent of the remainder of the forest, may be treated separately so as to avoid confusion. t Or watershed, or ranger district. FOREST TYPES Division Type Area Sawtimber M. ft. B. M.) Cordwood (Cords) Total Notes. — Brief comments or descriptions of types where necessary because of unusual features. Refer to type map if there is one. THE THEORY AND PRACTICE OF WORKING PLANS 215 OBJECT OF MANAGEMENT' Timber Types: f Woodland Types: SILVICULTURAL SYSTEM \ Description: Application: Marking Rules. * Separately for each division if desirable. t State objects briefly, also species to be favored and classes of material to be produced. j By types, and by divisions if necessary. 216 THE THEORY AND PRACTICE OF WORKING PLANS REGULATION OF YIELD Rotation: Division of Forest: Annual or Periodic Cut. REGULATION OF CUT* Limitation of annual cut for first period. Cutting plan for period by years, with proper references to cutting map. Tabulate amount to be cut each year. Unless forest or division has been covered by reconnaissance, it will probably be necessary to confine cutting plan to a few ensuing years — 4 to 10. Record of Regulation — Separately for Sawtimber and Cordwood. Year Total Merchant- able Stand Estimtd. Annual Yield Limit'n of Cut (Secre- tary's) Timber Cut Surplus (+)or Deficit (-)in Allowed Annual Cut (t) Accum- ulated Surplus Sale Free Use Total (+)or Deficit (-) * By divisions if desirable. This subject should be handled in greater or less detail according to available data. t Based on Estimated Annual Yield. THE THEORY AND PRACTICE OF WORKING PLANS 217 POLICY Division Protection: Importance of any special areas for protection. Refer to cutting map on which reserved areas should be shown. Free Use: Brief notes on volume of free use business, past, present, and future; character of material used; localities, etc. Any exceptions to general policy, or special points of importance. Refer to cutting map for free use areas. Sales: Any necessary comments on sales policy. Opportunities for desirable sales. STUMPAGE RATES Rates recommended with brief statement of reasons. Provision for future increase. Sawtimber (M. ft. B. M. Cordwood (Cords) Poles (Linear ft.) Lagging (each) 218 THE THEORY AND PRACTICE OF WORKING PLANS UTILIZATION * Cutting Prior to Creation of Forest: Brief notes. Acreage cut over by types, if possible. Amount cut. Refer to map showing cut- over areas. Methods of Logging: * Confine treatment of this subject to brief notes summarizing conditions. References to more detailed data should be listed in Appendix. THE THEORY AND PRACTICE OF WORKING PLANS 219 Accessibility of Timber: Include reference to improvements needed to open up timber stands. Costs of Logging and Manufacture: Markets, Market Conditions. Demand, Prices: 220 THE THEORY AND PRACTICE OF WORKING PLANS Si*. H pq CO i_j £ a CO "1 Pi -fl CO " 2 CO w ►J r o H 4-» o 1 15 CO SB tu > -a CO P a CD eg a & u PS m a 0) 13 > "3 3 O s < 9 o CO a w H CJ 3 > 1 « ! < 1 a o S3 So 3 c« 0>O0*O0iOOOO THE THEORY AND PRACTICE OF WORKING PLANS 221 W -a fc 8 w is ffl o H M « | & Z W & s u a z 3« (i w O hJ P-H < ~C/3 © 53 > a o V O W w w H > T3 a V a H E> <_> a o o "d > a u M o 9 o a o o "d > a 6 "3 u C5 E 3 a S3 ■g-a 1 w o C/3 3 Q a M o 3 oo o- O 6 " Oi Oi Ov D* O* O* ©* C^ 0» 0> 222 THE THEORY AND PRACTICE OF WORKING PLANS u & "3 a* W ug 3 1 cd P a; o H W 1 1 cd 0) P a u u O H P u to W h) o On 3 > cd P a V 1*4 O % a O CO en a o PM u 3 "3 > T3 cd P 3 o 3 u *o d Id 'I 3 U • S 1 a) *■" 1 § w o H C/3 T3 cd 0) a a> h a COftO ► O O M ► oaot 4 Cl <*3^ \THO t*. 4 H M M H M M >0 Ot Ot OiOi Oi THE THEORY AND PRACTICE OF WORKING PLANS 223 H S H z> < •« H w 3 XI w M ?! ■B CO pq a 0> 1 M o H 1 9' CO 3 "c3 en > . H P4 ca Mj3 £* W 6 S Up a 3 o r o 1 H u 3 ■3 > w CO S> w a "3 b i 1 a> 3 "3 H P > u 1 o 3 S < V 3 a I o Cfi § 1 < o a 1 i t ) *c 1 e 1 c > 1 1 1 i h- 5 1 < 5 < > > 4 OGWHMHMMMM 224 THE THEORY AND PRACTICE OF WORKING PLANS PLANTING * Areas Needing Restocking: Character Type Location Area Per cent of Forest Area • Total Notes. — Make reference to proper map showing planting and sowing areas. Location of areas should usually be done by Timber Reconnaissance parties. Summary of Results of Past Planting a;:d Snwijy - Policy: Brief statement of character of work proposed. * Details of tabulated plan for a period of years not necessary. Operations for ensuing year will be covered in annual plan after plan for district is formulated. Policy: THE THEORY AND PRACTICE OP WORKING PLANS 225 ■ Nursery, Equipment. Area in Seed Beds Area in Transplant Beds Total Area NURSERIES Capacity — Seedlings Transplants Proposed Annual Production Species Total 15 226 THE THEORY AND PRACTICE OF WORKING PLANS TIMBER RECONNAISSANCE Portions of Forest Covered: Division Block Area Year Timberland or Woodland Cost Per Acre Portions to be Covered in Order of Importance: Block Area Year Timberland or Woodland Cost Division Proposed Actual Estimated Actual Notes: Silvical Studies: Past. INVESTIGATIONS ' Proposed. Reforestation Experiments t * List studies and experiments approved by investigative committee and also any others which appear desirable for future attention. t If covered under Planting, make suitable reference. INDEX Abnormal forests, regulation of, 104 Administrative divisions, 25 Administrative plan, instructions for, 203, 209 outline for, 126, 198 Age classes, general classification, 5 in selection forest, 5 size of, 4 table of, 29 table of, in Austria, 183, 186 Allison, J. H., 15 Allowed annual cut (see regulation of yield) Amenagement (see working plans, practice of, in France) i'syn. forest organ- ization) Annual plans (see working plans, also cutting plan and planting plan) instructions for, in United States, 211 Area, determination of yield by, 44 Auhagen, 92 Austrian formula, determination of yield by, 52, 180, 200 Base lines (see also timber estimates), 10 Block (see also division of area), 20 Breymann's method, determination of yield by, 61 Brush disposal, place of in working plan (see also marking rules), 120 Bukowina, forest organization in, 180, 185 Bureau of Forestry, 190 Collection of data (see also reconnaissance) in Baden, 165 in Bavaria, 157 in United States, instructions for, 209 preliminary work, 8 survey of area, 9 Compartment (see also division of area), 20, 21 Control and revision (see working plans, control and revision of) Control book, 133 in Austria, 187 in Prussia, 143 Cotta, Heinrich, 92, 160 Coupes (see also determination of yield, in France), 176 Cutting and logging rules, place of in working plan, 121 Cutting and planting record (see control book) 997 228 INDEX Cutting cycle, record of in working plan (see also rotation), 120 Cutting plan, 97, 100 annual, 103, 121 general, 101, 121 in Bavaria, 155 in France, 174 in Prussia, 139 place of in revisions, 136 place of in working plan, 121 Cutting series, 99 in Saxony, 162 Department of Agriculture, 190 Secretary of, 201 Determination of yield, 43 by area, 44 by area and volume by age classes, 81, 82, 84 by area and volume by periods, 89 by area and volume for entire forest, 78 by volume on diameter classes, 66 by volume on growing stock, 47, 49 by volume on growing stock and increment, 52, 55, 59 by volume on increment, 49 in Austria, 185 in France, 66, 172, 176 in United States, 198 record of in working plan, 12 1 review of methods, 94 summary of methods, 43 Diameter-class method, determination of yield by, 75 application to America, 78 Direct method, determination of yield by, 81 Distribution of the age classes, 1, 4 advantages of comparison between actual and normal, 7 graphic comparison of actual with normal, 7 record of in working plan (see also tables), 116, 121, 136 Distribution of yield, 96 in France, 175 District Forester, 200, 213 Division of area, 20 block, 20, 21 boundaries of, 23, 25 coincidence with administrative divisions, 25 compartment, 20, 21 designations of, 23 in Alsace-Lorraine, 168 INDEX Division of area in Austria, 180 in Bavaria, 148, 151 in France, 172 in Prussia, 140 in Saxony, 160 principles of, 20 record of in working plan, 1 19 subcompartment (stand), 20, 21 working figure, 20 Estimates (see timber estimates) Fernow, B. E., see Introduction, p. xii Fire plan (see forest protection plan) Forest adjustment (syn. forest organization) Forest description, 17 essentials of, 17 in Alsace-Lorraine, 169 in Austria, 184 in France, 173 record of in working plan, 119 unit of, 19 Forest organization control of, in Austria, 180 in Bavaria, 157 in Prussia, 142 in Saxony, 159 in United States, 191, 200, 201, 209, 212 definition of, see Introduction, p. xi Forest organizer (see forest organization) Forest plan, see Introduction, p. xi section of National Forest Manual, 201 instructions in, 202 et seq. issued, 201 Forest protection plan, instructions for, 202, 207, 209, 212 outline for, 126, 196 Forest Service, 190 Forest types, record of in working plan, 214 Forsteinrichtung (syn. forest organization, which see) French method, determination of yield by, 66 Graves, Henry S., 2 Grazing management, plan of, instructions tor, 202, 205, 211, 212 outline for, 126, 195 Greeley, W. B., 106 Growing stock, normal, I, 4 229 230 INDEX Growing stock, actual (see reconnaissance and timber estimates) record of, in working plan, 116 Guzman, E., 185 Hartig, G. L., 138 Heyer's method, determination of yield by, 63 application to America, 65 Heyer, Carl, 65 Heyer, Gustav, 65 use in Alsace-Lorraine, 170 use in Baden, 166 use in United States, 200 Hufnagl's methods of determining yield, 2, 49, 75, 81, 82, 83 by age classes, 81, 82 by current annual increment, 49 by diameter classes, 75 formula for determining the yield, 83 application to America, 84 Hundeshagen's method, determination of yield by, 59 Increment, borer, use of, 2 current annual, 3 determination of, 1 determination of yield by, 49 importance of, 43 mean annual, 3 normal, 1 record of in working plan, 116 Indian method, determination of yield by, 72 Investigations, record of, in working plan, 226 Jagen (see working-plans practice, Prussia) Judeich, Friedrich, 53, 58, 59, 64, 84 Kameraltaxe (see Austrian formula) Karl's method, determination of yield by, 55 Limitation of annual cut (see regulation of yield) Logging unit (see also Block), 34 Management, object of, 33, 37 record of in working plan, 120, 215 silvicultural, Introduction, p. xi silvicultural method of, 33, 35 record of in working plan, 120, 215 Manual of procedure, 200 INDEX 231 Maps and tables (see also tables), 28 in working plan, 117 of stands to be cut (see also cutting plan), 98 sample sketch map, 27 Markets, influence of on sustained yield, 34 Market unit (see also working figure), 34 Marking rules, place of in working plan, 120, 210, 215 general, 199 Martin, Heinrich, 43, 53, 58 Masson, Methode de, 2, 49 Methode de 1883 (see French method) Method of treatment, determination of, 33 Moore, Barrington, 52, 66, 72 National forest manual, 201 National forests, 190, 191, 198 New reconnaissance, the, 191 Normal forest, its attributes, I Office of forest management, 191 Office of silviculture, 200 Organization (see forest organization) Paulsen (see also Hundeshagen), 60 Period methods, determination of yield by, 89 area-period method (syn. area framework, "flachenfachwerk"), 89 area-and-volume-period method (syn. combined framework, "kombin- iertes fachwerk"), 91 in Alsace-Lorraine, 169 in Austria, 185 in Baden, 164 in Bavaria, 147 in France, 173, 174 in Prussia, 138 in Saxony, 160 in Wiirttemberg, 163 volume-period method (syn. volume framework, "Massenfachwerk"), 90 Period of regeneration, record of in working plan (see also method of manage- ment, silvicultural), 120 Permanent improvement plan, instructions for, 202, 206, 21 1, 212 outline for, 126, 197 Planting plan, 128 annual, 128, 130, 131 general, 128, 129, 132 place of in revisions, 135 place of in working plan, 121, 224 262 INDEX Preliminary plans, in Austria (Bukowina), 180 in United States, 201, 203 Prussia, practice of working plans in, 137 Reconnaissance (see collection of data and timber estimates) estimates, method of, 14 record of in working plan, 115, 226 section of, 191, 199, 200 Regulation, in selection forest, Alsace-Lorraine, 170 in special cases, 104 of transition forests, 106 of turpentine forests, 108 of wood-lots, 108. of yield, denned, 42 record of in working plan, 121, 216 unit of, 33 Revisions (see working plans, control and revision of) in Alsace-Lorraine, 170 in Austria, 186 in Baden, 165 in Bavaria, 156 in Prussia, 142 in Saxony, 162 in United States, 213 Rotation, 33, 38 choice of, 40 customary rotations in Europe, 41 financial rotation (syn. of highest soil rent), 39 in Austria, 186 in Bavaria, 152 in Prussia, 141 latent rotation, 39 of greatest income (syn. of highest forest rent), 39 of greatest volume (syn. silvicultural rotation, economic rotation), 38 physical rotation, 38 record of in working plan, 120, 216 technical rotation, 38 Russian method, determination of yield by, 78 Sale policy, 198, 200 Schneider's formula, use or, 2 Section of reconnaissance, 191, 199, 200 Silvicultural management, plan of, instructions for, 204, 209, 211 outline for, 193, 212 system (see silvicultural method of management) Stand (see also subcompartment), 20, 21 INDEX 233 Stand, basis of differentiation, 22 selection of stands to be cut (see also cutting plan), 97 Stand method, determination of yield by, 84 application to America, 89 table (see tables) Statistics, record of in working plan, 220, 221, 222, 223 Strip surveys (see also timber estimates), 12, 192 Stumpage rates, minimum, 199, 200 place of in working plan, 121, 217 standard, 200 Subcompartment (see also division of area, and stand), 20, 21 Survey of area (see also collection of data), 9 Sustained yield, application of, 34 relation to increment, 43 total for national forests, 201 Tables (see also maps and tables) age-class table, 29; examples of, 31, 3 2 . alienation table, 29 area tables, 29 general stand table, example of, 29 in Austria, 184 in Prussia, 139 place of in working plan, 117 instructions for tabulations, United States, 209 stand tables, 29 . Timber estimates (see also collection of data and reconnaissance) base lines, 10 cost of, 17 in Austria, 182 in Bavaria, 150 in United States, 191, 192, 213.. 214 ocular estimates (see also reconnaissance), 13 requisites, 10 size of crew, 12 the strips, 12 time of, 16 Transition forest, regulation of, 106 Turpentine forest, regulation of, 108 number of crops operative annually, 112 Use per cent (see Hundeshagen's method) Uses of forest land, instructions for, 202, 207, 211, 212 outline for plan of, 127, 196 Utilization, record of in working plan, 218 234 INDEX Von Grebe, 92 Von Mantel's method, determination of yield by, 2, 47, 200 Von Stockhausen, 92 Wood-lots, regulation of, 108 Woolsey, T. S., Jr., 200 Working block (see working figure) Working circle (see working figure) Working figure (see also division of area), 20, 33 Working period, 121, 133, 208 Working plans conference, 8, 136, 158 record of in plan, 116, 136, 209 control and revision of, 133 documents, 113 contents and form, 113 foundations of, 1 outlines for, 122 American outline, suggested, 124 administrative plan, 126 appendix, contents of, 127 foiest protection plan, 126 foundation, 125 grazing plan, 126 maps, 128 orientation, 124 permanent improvement plan, 126 recommendations, 125 regulation, 126 uses of forest land, 127 Forest service outline, 192 Prussian outline, 122 Saxon outline, 124 ractice of, 137 in Alsace-Lorraine, 167 in America, 190; instructions for, 202, 203, 208, 211 in Austria, 177 in Baden, 164 in Bavaria, 147 in France, 171 in Prussia, 137 in Saxony, 159 in Wiirttemberg, 163 resume of, in Europe, 187 scope of, Introduction, p. xi sphere of, Introduction, p. xii value and need of, Introduction, p. xi index 235 Working plans officer (see forest organizer) Yale forest school, Introduction, p. xii Yield, determination of (see determination of yield) Yield tables, use of in estimating, 17 Zon, Raphael, 78 SHORT-TITLE CATALOGUE OF THE PUBLICATIONS OF JOHN WILEY & SONS NEW YORK London: CHAPMAN & HALL, Limited Montreal, Can.: RENOUF PUB. 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