S 531 .03 Copy 1 THE "ECONOMY" LOOSE LEAF NOTE BOOK COVER FILLERS No. 80 Ruled 2 sides, red marginal lines " 80-A Ruled two sides, no marginal lines " 81 Ruled 1 side, red marginal lines 40 " 82 Blank, not ruled on either side 40 " 83 Drawing Paper 30 " 84 Linen Ledger, for fine drawing 25 " 85 Metrically ruled, for Physics 25 " 86 Extra heavy, ruled 2 sides, red marginal lines, 36 " 87 Science, ruled in centimeter squares 36 40 sheets to pkg. 40 SCHOOL AND HOME EXERCISES IN ELEMENTARY AGRICULTURE B. M. DAVIS, Ph. D. PROFESSOR OF AGRICULTURAL EDUCATION AND DIRECTOR OF EDUCATIONAL EXTENSION, OHIO STATE NORMAL COLLEGE, MIAMI UNIVERSITY, OXFORD, OHIO; AUTHOR OF "AGRICULTURAL EDUCA- TION IN THE PUBLIC SCHOOLS" The Dobson-Evans Co., Columbus, Ohio, Publishers S531 ■D5 Copyright 1914 BY B. M. Davis ^ ©CI.A376473 JUN26I9I4 h^, PREFACE This manual of "School and Home Exercises in Elementary Agriculture" is an extension and revision of a series of exercises published by Miami University as a bulletin under the title, "Soil and its Relation to Plants." It is intended to supplement a good text-book on agriculture by giving more detailed and spe- cific directions for various types of laboratory, field, and home work. Each exercise presents a problem or project to be worked out by the pupil. The nature of the prob- lem or project is suggested by the title, and is further amplified by a brief note of explanation. This is fol- lowed by directions for performing the experiment or carrying out the project. Both explanations and direc- tions should be carefully read by the pupil before he begins the work called for by the exercise. Under application, which concludes most of the exercises, are mentioned familiar facts or practices which the ob- served results help to explain. Each exercise should be carefully written up by the pupil. The following order is suggested: 1 . Purpose or aim. 2. Material or apparatus. 3. Procedure. — Description of each step taken, and statement of all observations. 4. Results. — Summary of everything found out in the exercise. When possible, make summary in neat tabulation. 5. Conclusion. — Statement of conclusion reached. In some cases this will be a brief statement of results. 6. Sources of error. — If the exercise is an experiment a statement should be made of anything likely to cause error in results. 7. Remarl(s. — A record should be made of anything of interest noticed in the course of the work and not recorded under above headings. Whenever possible each pupil should do his work independently. Sometimes it may be convenient to have two or more pupils do the work of an exercise jointly, but each should make his own observations, take his own notes and make his own record. REFERENCES The general references at the end of each exercise are designated by numbers corresponding to num- bers in the following list. Special references are given by title. The first ten of this list are recent text-books of agriculture in common use. Nos. II, V, and VII are high school texts, the others are elementary texts, but are sometimes used in beginning high-school courses where pupils have had little or no agri- culture in the grades. The remainder of the references are books on special phases of agriculture and should also be supplied with the special references cited in various exercises. Most of these are Gov- ernment or State Publications which may be obtained free of cost or at slight expense. I. Agriculture for Beginners, Burkett, Stevens and Hill. Boston: Ginn and Co. II. Productive Farming, Kary C. Davis. Philadelphia: J. B. Lippincott Co. III. Agriculture for Common Schools, Fisher and Cotton. New York: Charles Scribner's Sons. IV. Beginnings in Agriculture, Albert Mann. New York: MacMillan Co. V. High School Agriculture, Mayne and Hatch. New York: American Book Co. VI. An Introduction to Agriculture, A. A. Upham. New York: D. Appleton and Co. VII. Elements of Agriculture, G. E. Warren. New York: MacMillan Co. VIII. Practical Agriculture, J. W. Wilkinson. New York: A^merican Book Co. IX. Agriculture for Young Folks, A. D. and E. W. Wilson. St. Paul: Webb Publishing Co. X. School Agriculture, M. N. Wood. New York: Orange Judd Co. XI. Insects Itjjurious to Vegetables, F. H. Chittenden. New York: Orange Judd Co. XII. Beginnings in Animal Husbandry, C. S. Plumb. St. Paul: Webb Publishing Co. XIII. First Principles of Soil Fertility, Alfred Vivian. New York: Orange Judd Co. XIV. Field Crops, Wilson and Warburton. St. Paul: Webb Publishing Co. APPARATUS AND MATERIALS Balances, Harvard Trip Scales _ $6.00 Weights (iron, I kilo to 5 grams) _ _ 1.08 Spring balances for milk record _ 2.50 Funnel, small, glass _ 15 Graduate, 50 ccm „ - .50 Glass Tubing, assorted sizes, ]/2 lb _ 25 Rubber tubing, V- root, and by the sweet potato, which is a modified fibrous root. Find and study good examples of each kind. DIRECTIONS: (a) Dig up a clover plant and remove the soil from it. Observe that it has a strong central root which joins the stem. Note arrangement and extent of smaller roots which are connected with this main root. Make diagram showing arrangement of root-system. (b) Dig up a single grass plant (wheat will do) with as many of its roots as possible, and remove the soil from them. Observe that the root system is composed of many roots about the same size. They project from the conical portion of the stem of the plant just below, or at the surface of the ground. Make diagram showing arrangement of root-system. (c) Dig up a number of common plants. Determine which have tap-roots, and which have fibrous roots. Make a list of common plants. Arrange in two columns, writing the names of tap- rooted plants in one, and the names of fibrous-rooted plants in the other. REFERENCES: I, pp. 27-28, 42: II. p. 8; IV. p. 107; V. pp. 127-128; VIII. p. 63; IX, p. 7; X, pp. 80-82. FIG. I Root system of a plant showing distribution of roots with reference to surface of the soil and soil moisture, and also effect of deep and shallow cultivation. EXERCISE 2 EXTENT OF THE ROOT-SYSTEM OF A PLANT EXPLANATION: In the preceding exercise the root-systems of a number of different kinds of plants were examined. The main fact common to both types of root systems is the provision made for root surface. The importance of root surface cannot be too strongly emphasized. The amount of food material brought to the plant by the roots is in proportion to the extent of these roots; the greater the total root surface the greater the absorbing capacity. The amount of root surface of a plant may be roughly determined by measuring the roots and finding their total length. DIRECTIONS: Select some plant (a corn plant will do) which is growing by itself. Carefully dig a trench around the plant to a depth of twelve or fifteen inches. The central ball or cylinder of earth will contain most of the roots. Remove, by digging, as much of the soil from the roots as possible, and remove the rest by washing. Before removing the plant, note direction of growth, whether branched or not, in what part of soil most numerous, and how near the surface the roots come. All these observations should be put together in a sort of diagram. (See Fig. 1 ) Remove the plant, saving all the roots. Measure each one, and find total length of ail the roots. With the best of care it will be impossible to remove all the roots. The real extent will be much larger than the calculated amount. The total length of all the roots of a well developed corn plant has been estimated to be over 1,000 feet; the total length of all the roots of a mature squash vine has been found to be about fifteen miles. APPLICATION: Methods of cultivation should take into account the fact that many of the roots, especially late in the growing season, are near the surface. Deep cultivation will destroy all such roots, and to that extent cut off the food supply of the plant, thereby lessening the yield of the crop. (Fig. 1) REFERENCES: I, pp. 29-30; II, p. 143; IV, pp. 57, 107; V, p. 129. The Roots of Plants, Kansas State Agricultural College, Bulletin 1 29. EXERCISE 3 ROOT-HAIRS EXPLANATION: The root hairs are the absorbing organs of a plant, i. e., they transfer the water and the substance dissolved in it from the soil to the rootlet. (Fig. 5) The size, appearance and arrangement of root-hairs may be easily seen on the roots of a young plant. DIRECTIONS: Put some seeds (radish or wheat seed) that have been soaking in water for about twenty-four hours, between two layers of cotton or cotton cloth (news-paper or blotting paper will do). Keep the covering moist. In two or three days roots will develop and will be covered with a thick fuzz of root-hairs. Observe the part of the root covered by root— hairs. The part of the root covered by root-hairs is called root-hair zone. Note also the length of root-hairs near the tip of the rootlet compared with the length of those at the opposite end of the root- hair zone. Select a seed plant having a straight root and put it on a piece of moist blotting paper. Mark with pencil the two extremes of the root-hair zone. Put away for several days, being careful to preserve the moisture (cover with inverted tumbler), and also being careful not to disturb the position of the root with reference to the marks. At the end of three to five days (a longer time if temperature is low) the root will have increased in length and with it the extent of the zone of root-hairs. The long hairs at the mark nearest the plant, will show signs of collapse. In a few more days they will begin to shrivel up. Thus new root-hairs are formed at the tip of the root while the old ones shrivel up and disappear. The root-hair zone is always about the same length. New hairs are formed about as fast as the old ones shrivel up, so that the tip of the root is always followed by the zone of root-hairs. In this way new feeding areas are constantly supplied to the root. APPLICATION: Since all the water and dissolved plant food must enter the root through the root-hairs, the condition of the soil should be such as will enable the tender rootlets to push their way easily through the soil in order to occupy as large a feeding area as possible. REFERENCES: I, pp. 27-28: II, pp. 8-9; IV, p. 108; V. pp. 122-123; VI, pp. 5-6; VII, p. 64; VIII, p. 64; IX. p. 8;X. pp. 80-81. EXERCISE 4 HOW THE SOIL HOLDS WATER (Capillary attraction or Capillarity.) EXPLANATIO When a pencil is dipped in water a film of water adheres to it. TTiis attraction of a solid for a liquid is called capillary attraction, or capillarity. A few simple experiments will make this action clear. DIRECTIONS: Set two square or rectangular pieces of glass in a pan of water, putting the two vertical edges together so that the pieces of glass will form an angle of two to five degrees. Note that the water in the narrow portion of the angle rises some distance above the level of the water in the pan. Here the capillary attraction is greater than gravity, for it is sufficient to draw the water upward for a short distance. The same may be shown by means of glass tubes of different diameters. The water in the tubes having the least diameter will rise to the greatest height. A lamp-wick carrying the oil upward to the flame is another and more familiar example. APPLICATION: Root-hairs are adapted for taking up water that adheres to soil particles. (Fig. 5) This fact is very important. It must be kept constantly in mind in putting the soil in condition for plant growth. The soil may be perfect as to food content and in other particulars, but if the water does not exist as capillary water, i. e., as films adhering to soil particles, the root-hairs are unable to do their work. REFERENCES: I, pp. 10-12; II. pp. 58-59; III. p. 19; V. p. 72; VI. p. 25; VII, p. 79; VIII. p. 44; IX, p. 8; X. p. 16. r^ FIG. 2 — To show osmosis. e:xercise 5 HOW WATER GETS INTO A ROOT-HAIR EXPLANATION: The root-hair may be considered as an elongated bag, filled with a liquid denser than water. When two liquids of different density are separated by a membrane, the less dense liquid tends to pass through the membrane more rapidly than the more dense liquid. This produces a greater pressure on the side of the membrane which is in contact with the liquid of greater density. The pressure thus exerted is known as osmotic pressure. This pressure may be shown in several ways. One method is as follows: DIRECTIONS: Material. A wide-mouthed bottle, an egg, a quarter-inch glass tube six inches or more in length, a piece of candle one-half inch long, a wire somewhat longer than the glass tube. Procedure. Crack the large end of the egg and remove part of the shell, being careful not to break the shell membrane. The shell should be removed from an area about one-half inch in diameter. Remove the shell from the small end over an area equal to diameter of glass tube. Bore a hole through the piece of candle just big enough to receive the glass tube. The position of the hole should correspond to the position of the wick in the candle. Heat the end of the candle and stick it over the small end of the egg so that the hole in the candle lies just over the hole in the shell. With a hot wire melt the edges of the candle so as to fix it firmly to the egg. Place the glass tube in the opening of the candle and with the hot wire make the joint water-tight. Break the egg membrane of the small end of the egg by passing the wire into the egg through the glass tube. Now fill the bottle with water, and place the egg on the bottle so that the exposed egg membrane of th^; large end remains below the surface of the water. In about an hour the white of the egg will be seen rising in the glass tube. The water from the bottle passes through the egg membrane and pushes the egg contents into the tube. APPLICATION: Sometimes the water current may be reversed in a plant. TTiis happens if the roots are surrounded by a solution denser than the root-hair contents. For example, salt or brine coming in contact with the root-system of a plant withdraws the water, causing the plant to wilt and sometimes die. Salt is sometimes said to poison plants; it does so through osmotic action, withdrawing the water from the plant. REFERENCES: I, pp. 31-32: II. pp. 14-15: IV, pp. 108-109; V, pp. 124-125; VI. pp. 43-44; VII, p. 65; VIII. p. 65; X. p. 81. Fig. 3. Apparatus for demonstrating various phases of erosion. EXERCISE 6 ACTION OF WATER IN SOIL FORMATION EXPLANATION: The chief factor in soil formation is water. The erosive action of water during and immediately after a shower is familiar to everyone. On a large scale the same action is involved in wearing away the mountains and in carrying the material to lower levels, where it is deposited in the form of soil. The whole series of erosive processes may be shown at work by means of an easily constructed apparatus (suggested by Osterhout in Experiments With Plants, p. 110). DIRECTIONS: Three boxes, each about three and one-half feel long, one foot wide and six inches deep, are needed. These should be hinged together in a series. Strips of leather the width of the box will answer very well for hinges. Setting up apparatus. The next step is to arrange the sections so that they will stand at different levels. The first one should be level; the second inclined about fifteen degrees; the third inclined about thirty degrees. Strong props must be used to hold the second and third sections in place. The apparatus as set up is shown in Fig. 3. The sections must now be made water tight. If they are set up out of doors they may be made sufficiently free from leaks by stopping the openings with wet clay. Some provision must be made to carry the water from the upper section to the middle section, and from the middle to the lower. Short strips of oil cloth or tin extending over the joints will answer this purpose. If the apparatus is to be set up in the schoolhouse more care must be taken to prevent leakage. The best way will be to line the entire length of the trough with a strip of oil cloth thirteen feet long and two feet wide. At the lower end gather up the oil cloth so as to form an outlet to carry away the surplus water. After the apparatus has been set up according to either of the above methods, the middle section should be filled with sand, and the upper section with clay. A small piece of sod may be placed in the upper section near the middle, having its surface level with the clay. The clay of the latter may be made to vary in hardness in different places by mixing it with sand. The lower section should be empty. A bucket 0? water placed above the highest point of the upper section, and a siphon made of small rubber hose completes the apparatus. Action. Start a small stream of water from the siphon and allow it to trickle down the entire length of the trough. "The clay mixture in the upper section will behave in the same way as rock (only the action will be more rapid), and will show clearly how rock is sculptured by running water, how masses of it become detached and fall off, and how as these are carried down stream they lose their sharp edges." "In the middle section we will see landslides, terraces, meanders, oxbows, bubbling springs (where an obstacle occurs) and all other features of stream action. In the lower section we shall see alluvial fans and cones, deltas, beaches, the deposit of coarse materials near shore, and finer materials, further, all the features of lake and ocean formations." (Osterhout.) APPLICATION: This experiment should be followed by a study of erosion on farms near the school. The hill sides should receive special attention. Compare the loss of soil due to erosion on bare hill sides with the loss on those covered with trees and shrubs. Much difference may usually be seen. This suggests a means of preventing soil loss which will at the same time make otherwise bare hill sides productive. Hill sides too steep to cultivate may be covered with trees like the yellow locust. In a few years the trees will not only check the loss of soil by erosion, but will yield valuable returns in fence-post timber. REFERENCES: I, pp. 3-5: II. pp. 45-56; III. pp. 3-4; IV. pp. 54-55; V, pp. 67-71 ; VI. p. 13; VIII. pp. 25- 27: X. pp. 2-3; XIII, pp. 47-60. EXERCISE 7 SOIL AND SUBSOIL EXPLANATION: In a climate such as we have in the Ohio Valley, the surface of the earth to a depth of from six to twelve inches is called soil. Below the soil is the subsoil. According to King, this distinction "grows out of the fact that oftentimes when the deeper soil is brought to the surface, it is found unproductive for a time, and, besides, there is a sharp line of demarcation of color of the two portions." The difference between soil and subsoil should be studied by actual observation. DIRECTIONS: The sides of a trench or steep bank of a road will furnish a good illustration of soil and subsoil. It will be necessary to scrape off an inch or more of the surface so as to expose the soil and subsoil. The soil may be easily recognized by its dark color. All below is the subsoil. Where no such situations are available the same facts may be shown by digging a hole or trench to a depth of eighteen inches and examining its sides as above indicated. Collect a sample of the soil (a large handful) for use in the next exercise. REFERENCES: I. p. 1 ; II. pp. 56-57; V, pp. 68; VI. p. 10; VIII. p. 24. EXERCISE 8 WHAT SOIL IS MADE OF EXPLANATION: Soil is a mixture of sand (rock fragments), fragments of organic matter (animal and plant refuse), and finer particles known as silt or clay. The amounts of these vary with different soils. DIRECTIONS (a) Examine a small amount of the sample taken in previous exercise. Note different sizes, shapes, and general appearance of particles. (b) Put enough of the soil in a six- or eight-ounce bottle to fill to a depth of one and one-half inches. Fill the bottle with water, cork and shake vigorously for one minute. Allow the mixture to settle, and watch the process. Note the kinds of particles that reach the bottom first, what next, and so on. Set away until the next day. There will then be seen several layers of material as follows: coarse sand on bottom, fine sand next, silt above this, and clay on top. Floating on top of the water and perhaps lying on top of the clay may be seen some dark particles. These are organic materials or humus. APPLICATION: AH soils are composed of a mixture of sand, clay, and humus. These three materials occur in various proportions. Soils are named according to the relative amounts of these materials: In a sandy soil, sand predominates; in a clay soil, clay predominates; in a muck soil, humus or organic matter predominates. Sandy loam is a sandy soil mixed with humus; a clay loam is a clay soil mixed with humus. A careful study of the different kinds of soil on the farms near the schoolhouse should be made and their distribution shown on a map drawn of these farms. REFERENCES: I, pp. 1-6; II, pp. 42. 50: III, pp. 9-10; IV, pp. 59-61 ; V, p. 68; VI, pp. 10-11; VII, pp. 75- 76; Vin, pp. 30-31; IX, pp. 18-19; X, pp. 10-13; XIII, pp. 31-46. EXERCISE 9 KINDS OR TYPES OF SOIL EXPLANATION: In the previous exercise it was seen that the sample of soil was made up of materials of different kinds: sand, clay, and humus. It is important to know the chief properties of each kind. DIRECTIONS: Material. For this and some of the subsequent exercises, a supply of each type of soil will be necessary About one gallon of each will be enough. Each kind of soil should be as pure as possible. Sand may be obtained from the sand bars of any brook or creek. It should be washed thoroughly to remove the clay and other impurities. The washing is done by stirring the sand in a bucket of water and then pour- ing off the muddy water. Repeat until the water comes off clear. Clay may be found almost pure in the subsoil in many places. The steep bank of a "cut" in a road often has a streak of nearly pure clay in it. The clay should be dried and then pulverized. Humus or decaying organic matter may be found at the base of a rotten stump or under a rotten log. Avoid large pieces. The fine black material is most desirable. Each kind of soil should be thoroughly dried and kept in a dry place. General Characters. Examine a small quantity of each type and compare with observations in previous exercise. Behavior Torvard Water. (a) Take about one cubic inch of each kind of soil and add enough water to make a plastic mass. Note any changes in appearances or behavior while the water is being added. Compare the effect of water on the three kinds, especially as to changes of color and resistance to handling (i. e. rel- ative tendency to become sticky). (b) Mould each kind into a ball and put away to dry. When dry note the effort necessary to crush or break up the balls of each kind. (c) Fill three shallow boxes level full (baking powder can-lids will do), one with humus, an- other with sand, and the third with clay. Add enough water to saturate each thoroughly. Set aside until the water evaporates, leaving the soils dry. Note how long it takes for each to become dry and also the amount of shrinkage in each. APPLICATION: This exercise shows that clay is responsible for many of the difficulties of handling soil, e. g., ten- acity, retention of water, baking, cracking, etc. Many of the problems of soil management are really questions of how to deal with clay. When a soil is made easier to work its texture is said to be improved. Good soil texture is quite as important as its content of plant food. REFERENCES: I, pp. 1-6; II, pp. 50-55; III, pp. 9-10; IV, pp. 59-61; V, pp. 68-69; VI, pp. 11-12; VII, pp. 77-78; VIII, pp. 30-31, 33-37; IX, pp. 18-19; X, pp. 10-13. EXERCISE 10 HOW CLAY MAY BE MODIFIED EXPLANATION: The tenacity of clay and some other of its objectionable features are due mainly to the small size of its particles. Any improvement of clay must take this into consideration. The purpose of this exercise is to show some ways of modifying clay, thereby improving its texture. DIRECTIONS: Effect of mixing coarse organic material on the texture of cla^. Take four samples of clay (equal quantities); mix (I) with one-fourth its volume of coarse hu- mus, (2) with one-third its volume, (3) with one-half its volume, and keep (4) as a control. Add enough water to each to form a stiff plastic mass. Note the effect of the humus on the tenacity of clay. Mould each into a ball. When it has hardened and become dry, test hardness and resistance by breaking. Effect of lime on the texture of clay. Take three equal quantities of clay (say 100 grams) and number them (I), (2) and (3). To (1) add 5 per cent of its weight of slacked lime, to (2) 10 per cent of its weight of slacked lime. Use (3) as control. Mix each thoroughly so that the lime may be evenly distributed, and add just enough water to make a plastic mass. Mould each into a ball and allow to dry thoroughly. Test the resistance of each by dropping upon a brick or other hard surface. Beginning with (2), drop from a height of 2, then 4 inches, and so on, noting the distance through which it must fall in order to break. Try (1) and (3) in the same way. The distance through which the balls must fall in order to break will indicate their relative tenacity. Further tests may be made by noting the ease or difficulty in breaking or crushing the fragments of each kind. The lime has changed the texture of the clay and made it less tenacious. Action of lime on clay. The action of lime in producing the above modification of clay is probably due, at least in part, to flocculation, i. e. bringing the smaller particles together to form compound particles or granules. This may be shown as follows: Mix a small amount of slacked lime in a tumbler of water (better use rain water). Put the same amount of water in another tumbler for control. Now add to both tumblers of water five times this amount of powdered clay. Stir the contents of both and allow to settle. In the one to which the lime has been added flakes or masses of material will be seen. The effect of the lime has been to flocculate the clay. After 24 to 48 hours, when the particles in both tumblers have settled, examine the sediment. The sediment in the tumbler to which the lime has been added will be granular while the sedim.ent in the other will be finely divided. Effect of burning on cla\). Put a piece of clay in a hot fire and burn it for several hours. When cool, if it has been heated enough, it will break easily and show very different properties from unburnt clay. APPLICATION: The experiments performed in this exercise give meaning to some common farm practices. The use of coarse barn yard refuse on soils where clay predominates not only adds fertility (making plant food available), but also improves the texture of the soil by separating the fine particles, thus making a clay soil more easily worked. Lime not only tends to make a clay soil granular but it also serves to neutralize in some instances the acid in the soil. Lime is applied at the rate of about twenty bushels to the acre once every four or five years. When wood was plentiful it was the practice in some places to improve clay soil by burning. It must be understood that these methods are effective only when the soil is well drained. REFERENCES: I. pp. 20, 26; II, pp. 54, 75, 77; VII, pp. 83-84; X. pp. 11-12. n n n n FIG 4 — Apparatus for demonstrating percolation and capillary action of different soils. EXERCISE 11 FLOW OF WATER THROUGH DIFFERENT KINDS OF SOIL EXPLANATION: There is a great difference in soils shown by their behavior toward the water that falls on their surfaces. In some soils the water is taken up so readily that shortly after a shower very little evidence of rain is noticed. In others, after the rain, water stands in puddles and it is some time before the water disappears from the surface; even then, the soil is soggy or muddy. How the character of the soil affects its power to take in water that falls on its surface may be shown by a simple experiment. DIRECTIONS: Apparatus. Four student lamp chimneys, a rack to hold them, and a pan or four tumblers to catch the water that drains from the tubes will be needed. (Instead of student lamp-chimneys, ordinary lamp chimneys may be used.) Arrangement of Apparatus. Tie pieces of cheese cloth over the small ends of the chimneys. Fill them nearly full, respectively, of dry sand, dry clay, dry humus, and dry garden soil (loam). Place tubes in rack. The apparatus as set up is shown in Fig. 4. Procedure. Pour water into the upper end of each tube and note how long it takes for the water to begin to drip from the lower end of the tube. It will be seen that the humus and sand take in water and allow it to flow through quite readily, the garden soil less readily, and the clay quite slowly. Repeat the experiment, using dry garden soil and two tubes. Pack the soil tightly in one and leave it loose in the other. APPLICATION: These two experiments show that the power of soil to take up water depends upon two things: the size of the soil particles, and the compactness of the soil. Clay and compact soils take in water so slow- ly that most of it runs off and is lost. And as it runs off, it carries away some surface soil leaving the surface irregular. The texture of such soils may be improved by keeping them open by plowing (fall plowing) and tillage, thus increasing their water-holding capacity. The texture may be further improved by methods in- dicated in the last exercise (coarse barnyard material, lime), REFERENCES: I. pp. 12-13; II. pp. 60-61 ; III. p. 21 ; IV. p. 69; V. p. 73; VI. p. 21 ; VII. p. 85; VIII. p. 46;X. pp. 19-20. EXERCISE 12 HOW WATER MOVES UPWARD THROUGH DIFFERENT SOILS EXPLANATION: Attention has already been called to the phenomenon of capillarity, or capillary attraction. (Ex. 4.) Water exists in the soil chiefly (a) in the form of capillar'^ xvaler, i. e., water around soil particles and at the points of contact between the particles; and also (b) as free water, i. e., water that completely fills all the spaces between the soil particles. In the upper layers of the soil, the water exists as capillary water; in the deeper layers, it exists as free water. The level of the free water is known as the water table. If a hole be made in the ground, as, for example, a well, the water will rise to a certain level; this level is the water table. (Fig. 1). The position of the water table varies with the season, being influenced by rainfall, atmospheric pressure, etc. In heavy, undrained soils, especially in low places, the water table is very near the surface of the ground. Hence the importance of drainage. The feeding area of the roots is in the region of the capillary water. If the water table is near the surface, the feeding area will be shallow and the plants will be shallow-rooted. As the plant removes the water from the feeding area, this water must be restored by capillary action from the area of free water below. It thus will be seen what an important role capillarity plays in plant nutrition. Capillary action varies in different soils both as to rate of water movement and also as to the height to which the water may be raised. This difference may be shown by means of apparatus used in previous exercise. DIRECTIONS: Arrange apparatus as in Exercise 1 I, using the same soils (dry). In the experiment, the lower ends of the tubes should extend about one-half inch below the surface of water held either in a pan, or in a tumbler for each tube. Note the rate at which the water rises in each tube, and also the height of water at the end of four or five days. In the tube of sand the water rises rapidly but soon stops, while in clay it rises slowly but finally reaches the top. The sand is composed of large particles, while the clay is composed of very fine particles. The results of this experiment would indicate that the power of soils to lift water depmnds upon the size of their particles; in other words, upon their texture. APPLICATION: This exercise shows the disadvantage of sandy soils, for they have little power to take up moisture from below. As has been suggested, this is because of the large soil particles and soil spaces. Such soils may be improved by the addition of fine stable manure, or of other barnyard refuse, so as to fill up the soil spaces and furnish finer particles. Temporary improvement may be made by compacting the soil, e. g., by means of a roller. This exercise also shows the value of clay soils or soils made up of fine particles. The property of clay which enables it to raise water through considerable distance makes up, in a measure, for some of the undesirable properties which have already been pointed out (Ex. 9). We have seen that water passes through clay soil slowly, and that the water of a rain is apt to run off rather than to sink into the ground. The value of drainage should be emphasized in this connection. During wet weather the free water area is near the surface of the ground, thereby restricting the feed- ing area of the plants to the first few inches of the soil, and in low places coming so near the surface as to shut off this area entirely. The latter result is well illustrated in nearly every locality where clay soils predominate. In low places in fields in such localities, the grain is frequently "drowned out," or if not "drowned out," the stalks of grain are slender and unfruitful. On the other hand, during hot dry weather the water table sinks so low that the capillary connec- t!cn wi h ihe 'hallow soil area where the roots are distributed is broken. Plants then suffer from insuffi- cient supply of water. The remedy for these two undesirable extremes is drainage. Good drainage means the control of the level of the water table. If, during the early wet season, the water table is some distance below the surface of the ground, the depth of the feeding area of the roots will be increased. When the dry season comes, the roots will be deep enough to be always supplied with capillary water. (Fig. 1). Drainage is also important in its influence upon soil ventilation, soil temperature and the increase of available plant food. With good drainage and the improvement of texture by means of manures or lime, clay lands are very valuable. REFERENCES: I. pp. 14-15: II. pp. 61-62: III, p. 20; IV. p. 69; V. p. 73; VI, p. 21 ; VII. p. 85; VIII, > 44; X, pp. 16-17: XIII, pp. 79-81. EXERCISE 13 EFFECT OF INTERRUPTING THE CAPILLARY CURRENT EXPLANATION: The effect of breaking the capillary connection between the free water below and the feeding area above has already been noticed. The effect may be shown by a simple experiment. DIRECTIONS: Fill a lamp chimney, such as used in Exercises I I and 12, with dry garden soil to a depth of about two inches; fill the next one and one-half inches of space with dry straw or weeds; fill the remainder of the tube with dry garden soil. Fill another chimney with garden soil without straw or weeds. Place the tubes with their ends below the surface of the water as in Exercise 12. Note the rise of water in the first tube, and compare with rise of water in second tube, APPLICATION: Often in farm practice (bad practice) a field is covered after harvest with a heavy growth of grass and weeds. In the spring these are plowed under. Later, if the season is dry, the crop suffers from drought; the water cannot get above the layer of weeds into the feeding area of most of the roots, just as illustrated in the foregoing experiment. By fall plowing this condition may, in part, be avoided, REFERENCES: V. p. 82. EXERCISE 14 AMOUNT OF WATER HELD BY DIFFERENT SOILS EXPLANATION: In Exercise 1 I a variation may have been noticed in the amount of water necessary to be added to the different tubes before it began to drip from the bottom of the tubes. Some required more water than others. This was due to the difference in capacity of different soils for holding water. The amount of water that each kind of soil is capable of holding may be easily determined. DIRECTIONS: In addition to tubes and rack, as in Exercise I i , balance and weights will be needed. After tying cloth over the bottoms of four tubes, weigh each tube and keep a record of the weight. The tubes should be numbered in order to avoid confusion. Now fill each tube about half full, tube (I) with dry clay, (2) with dry humus, (3) with dry sand, (4) with garden soil. Weigh each one and re- cord the weight opposite the weight of the tube. Add water to each tube until the entire soil is wet. Cover the tops and allow excess water to drain off. Weigh each tube and record the weight with the entry made of the previous weights of that tube. With these data calculate the percentage of water held by each kind of soil as follows: Find the actual weight of dry soil by subtracting the weight of the tube (first weight) from the weight of the tube plus dry soil ; next find the weight of water by subtracting weight of tube plus dry soil from weight of tube plus wet soil. Determine what percentage the weight of the water is of the weight of dry soil. It will then be found that the humus will hold a much larger percentage of water than any of the other soils, while the sand will hold the smallest percentage. The clay and the garden soil will hold more than the sand. APPLICATION: The value of adding organic matter to soils, especially to sandy soils, is here emphasized. It not only helps to increase the capillary power of the sandy soils, and adds plant food, but makes them hold water more effectually. We have another point here in favor of clay soils. But this point is sometimes a disadvantage, e. g., in the early spring. Clay soils are cold because ihey contain so much water. Deep fall plowing, and shallow plowing or discing early in the spring may, in part, remove this difficulty. Fall plowing keeps the water at a lower level, and early shallow spring plowing hastens the evaporation of the water. Drain- age will remove the water from the upper part of the soil and thus prevent the loss of heat through evapo- ration of water. Sandy soils may generally be planted to crops much earlier in the spring than clay soils. REFERENCES: I, pp. 10-12: II. p. 61 ; III, pp. 21-22; IV. p. 68; V, p. 73; VII. pp. 79-80; VIII, p. 47; IX, p. 20; X, p. 16. a EXERCISE 15 EVAPORATION OF MOISTURE FROM SURFACE OF SOILS— DEW EXPLANATION: The notion that dew "falls" still obtains in the minds of many. A simple experiment will show where part of the moisture which we call dew comes from. Part of the moisture, of course, comes from plants, for they are constantly giving off moisture (transpiration) but a good deal of it comes from the ground. DIRECTIONS: Invert a tumbler on the surface of moist soil and leave it over night. Drops of moisture (dew) will be seen the next morning clinging to the inside surface of the glass. APPLICATION: A great deal of moisture is constantly being evaporated from the soil. At night it is condensed on cold objects in the form of dew. In the care of growing crops, it is important to reduce the loss of water through evaporation to a minimum. REFERENCES: II, pp. 62-63; V, p. 74; VII. p. 85; VIII, p. 46; IX. p. 20; X, p. 20. i Fig. 5. Diagram of a plant showing its most Important relations: sunlight, moisture, oxygen, and soil. EXERCISE 16 HOW TO KEEP MOISTURE IN THE SOIL. SOIL MULCH EXPLANATION: The problem of having a large supply of moisture in the soil and keeping it there, except when used by the plant, is an exceedingly important one. How to keep moisture in the soil may be readily shown. DIRECTIONS: Two one-quart tin cans, balances, and weights will be needed. Fill one can nearly full of damp garden soil; fill the other to within one and one-half inches of the lop with the same kind of soil and fill the rest of the space with dry garden soil. Weigh each can thus prepared and keep record of the weights. At the end of five or six days weigh again. The difference between the two weights of each can represents the loss of water through evaporation. Calculate the percentage of loss of water in each. The loss of water in the second can will be very slight compared with the loss in the first. The layer of dry soil on the second can acts as a blanket, keeping the moisture from evaporating. This covering is known as a mulch. (Fig. 5.) APPLICATION: In farm practice, stirring the soil forms a dry top layer and prevents the loss of water. It also pre- vents the soil from baking. Stirring the soil is especially important in times of drought. REFERENCES: I. pp. 12-13; II. pp. 62-63; III, pp. 44-45; IV, pp. 89-93; V. pp. 74. 83; VI. pp. 32-33; VII. pp. 85-86; VIII. p. 47; IX, pp. 20. 26; X. pp. 20. 46; XIII. pp. 70-71. EXERCISE 1 7 AIR IN SOILS A NECESSITY FOR PLANT GROWTH EXPLANATION: Plants as well as animals must have oxygen. Part of the oxygen supply of the plant must come by way of the roots, besides, the roots themselves need oxygen. A simple experiment will illustrate the necessity of roots being supplied with oxygen. DIRECTIONS: Cuttings of Wandering Jew (tradescantia) or some other plant that roots easily from cuttings and two tumblers must be provided. Put one cutting in a tumbler of wet sand and another in a tumbler of puddled clay (clay that has been wet and stirred until it forms a pasty mass). Keep the contents of both tumblers moist, being espe- cially careful not to allow the clay to get dry enough to crack. In a short time the cutting placed in the sand will take root and in a few weeks it will show a decided growth. The cutting placed in the clay will probabbly die in a few weeks. The chief difference in the two instances is in the amount of oxygen. The same thing may be shown in another way. Put one cut- ting in fresh well-water and another in water that has been boiled for some time and then cooled. Boiling the water drives off the oxygen. After a few weeks the same variation will be shown as in the experiment above. APPLICATION: We have here an explanation of why in low, poorly drained places plants are "drowned out." "Smothered out" would more nearly express the truth. Plowing and draining the soil, and, to a certain extent, cultivation, help to give the roots oxygen. When the texture of clay is improved by making the soil spaces larger, not only is a larger feeding area secured (an area containing capillary water), but also a breathing area (soil spaces filled with air for the roots). REFERENCES: I. p. 18; II, p. 17; IV, p. 76: V, p. 76; VII, pp. 81, 94-95; VIII. pp. 52-53; IX, p. 20. i EXERCISE 18 FERTILITY OF THE SOIL. PLANT FOOD EXPLANATION: The plant must have certain substances that are dissolved in the water of the soil. These substances that are taken into the plant from the soil are known as available plant food. DIRECTIONS: Fill two cans having holes punched in bottoms for drainage, or flower pots, with clean sand (sand that has been washed as directed in Ex. 9). Plant the same number (six) of grains of wheat in each. Keep one wet or moist with rain water. Keep the other in the same condition as to moisture with rain water to which has been added plant food at the rate of two compressed tablets to each pint of water.* For a while there will be no difference in the growth of the plants in the two cans. In the course of two or three weeks, when the food stored up in the grains is exhausted, the plants in the first can will cease to grow or grow very little, while those in the second can will continue to grow vigorously. The substances added to the rain water used in the second can are necessary to the plant's growth. Such substances when applied to soils are known as fertilizers. REFERENCES: I, pp. 22-26; II. 15, 81 ; III, pp. 10-11; IV, p. 99; V, pp. 9-66, 98-100; VI, pp. 40-42; VII. pp. 60-64, 113; VIII, pp. 1 28- 1 30 ; IX, pp. 10-11; X, p. 49 ; XIII, pp. 1 2-47. Renovation of Wornoui Soils, U. S. Department of Agriculture, Farmers' Bulletin 245. *N0TE: Each tablet is composed of: Common table salt [sodium chloride) 2H eraina (.162 erams); plaster of Paris — gypsum (calcium sulphate]. 2H stains (.162 £ramss); Epsom salts (maenesium sulphate, 2^ grains, (.162 grams); phosphate of I'me, neatly the same as burned bones (calcium phosphate). 2H grains (.162 grams); East India sall-petre — nitre (potaisium nitrate) 5 grains (.325 grams); compound of iron and chlorine (ferric chloride), nearly 1-10 grains. These tablets may be obtained at the rate of ten cents a box from Edward F, Bigelow, Sound Beach, Conn. i EXERCISE 19 COMMERCIAL FERTILIZERS EXPLANATION: The tablets used in the previous exercise contain nearly all the substances that the plant derives from the soil. All but three of these (nitrogen, phosphorus, and potassium) are generally found in the soil in sufficient quantities for the needs of the plant. The "essential ingredients" of a fertilizer are sub- stances containing- these elements: i. e., substances which supply (a) nitrogen, as nitrate of soda, dried blood, hoofmeal, etc., (b) phosphorus in form of phosphoric acid as bone meal (raw or steamed), min- eral phosphates, etc., (c) potassium in form of potash as wood ashes, kainite, muriate or sulphate of pot- ash, etc. A complete fertilizer is one that contains nitrogen, phosphoric acid, and potash in proportions supposed to be suited to the needs of certain crops. Such a fertilizer is made by mixmg substances con- taining the basic ingredients in such a way as to give the desired proportion of nitrogen, phosphoric acid, and potash. It is often the practice to use substances rich in these "essential ingredients" and dilute the mass to the desired strength by means of some inert material such as dry earth. Materials used in this way are called FILLERS. A 2-8-4 fertilizer means one that contains 2 per cent nitrogen, 8 per cent phos- phoric acid, and 4 per cent potash. If the percentages of available basic ingredients are known it is an easy matter to calculate the value of a fertilizer. DIRECTIONS: The percentages of ingredients are indicated on the fertilizer tag or label if sold in a state where fertilizers must be guaranteed. The list of ingredients on a fertilizer tag or label is often misleadmg or, at least, confusing. Only the lowest staled amount of available nitrogen, phosphoric acid, and potash should be considered. The following example of list printed on fertilizer tag will illustrate this point: Nitrogen L64 to Nitrogen as ammonia 2.00 Soluble phosphoric acid 5.00 Reverted phosphoric acid - 3.00 Insoluble phosphoric acid _ _ I -00 Total phosphoric acid 10.00 Phosphate of lime 22.00 Available phosphoric acid - 8.00 Potash 3.00 ^' Sulfate of potash '-64 In this fertilizer the lowest stated amount of nitrogen is 1.64 per cent; of available phosphoric acid, 8; of potash, 3. In other words this is a 1.64-8-3 fertilizer. Sometimes nitrogen is expressed in terms of ammonia. Ammonia contains 82 per cent of nitrogen. Two per cent ammonia would therefore con- tain .82 of 2, or 1.64 per cent, nitrogen. In order to determine the value of the plant food in a fertilizer three easy calculations are necessary: (1) Determine in pounds from the percentages given in the guaranteed analysis the amounts of nitro- gen, phosphoric acid, and potash in one ton (2,000 pounds). For example, the above fertilizer contains 1.64 per cent nitrogen, 8 per cent phosphoric acid, and 3 per cent potash. 2000X.0I 64=32.8, or 32.8 pounds of nitrogen. 2000X-08=i60, or 160 pounds of phosphoric acid. 2000X-03=60, or 60 pounds of potash. (2) Calculate the value of each ingredient at average market value per pound for nitrogen, phos- phoric acid and potash. These values change somewhat from year to year, but are published annually 2.46 per cent 3.00 " 6.00 " 4.00 " 2.00 " 12.00 " 24.00 " 10.00 " 4.00 " 2.46 " in state fertilizer-inspection circulars. For 1913, the values quoted are nitrogen 19 cents, phosphoric acid 6 cents, and potash 6 cents. On this basis the value of 32.8 pounds of nitrogen at 19 cents is $6.23; of 160 pounds of phosphoric acid at 6 cents is $9.60; of 60 pounds of potash at 6 cents is $3.60. (3) Add the values thus obtained in (2) : $6.23+$9.60+$3.60=$ 19.43. The selling price of such a fertilizer may be from $27 to $30 a ton, or at a profit of $7.57 to $10.57. This profit covers cost of mixing, freight, storage, agent's commission, loss from credit and bad debts. In buying a complete commercial fertilizer the total value of plant food should be calculated, and this amount subtracted from the dealer's price. The difference should not exceed a reasonable allowance for profit, — for example, if the total value of plant food is $19.43 per ton and the dealer's price is $30.00 a ton, the difference or profit of $10.57 is probably too great. Problems : 1. Find the value of plant food in a ton of a 1-10-4 fertilizer. 2. If a 4-8-4 fertilizer sells at $32 a ton, and a 1-7-5 fertilizer at $26 a ton, which fertilizer al- lows the dealer the greater profit? 3. A fertilizer tag shows the following guaranteed analysis: Water 1 2.0 to I 4.0 per cent Ammonia 2.0 " 3.0 Available phosphoric acid 8.0 " 1 0.0 Phosphate of lime 21 .0 " 25.0 Insoluble phosphoric acid 2.5 " 3.0 Potash 8.0 " 9.0 Sulfate of potash - 1 2.0 " 1 4.0 What is the percentage each of nitrogen, phosphoric acid, and potash that should be considered in estimating the value of this fertilizer? 4. Secure from dealers lists of fertilizers containing guaranteed analyses and prices per ton. Cal- culate value of plant food in each and compare with selling price. Sometimes prices are quoted at so much per unit. A unit is 20 pounds. To find price of a ton multiply price of one unit by 100. APPLICATION: These problems illustrate a practical application of arithmetic in estimating the value of a commer- cial fertilizer. One should always remember that the lorvest slated amount of available nitrogen, phos- phoric acid, and potash are the only materials to be considered in a guaranteed analysis, although other statements frequently occur in the printed analysis of a fertilizer. State Experiment Stations or State Departments of Agriculture furnish bulletins giving analyses of various commercial fertilizers on the market. By means of these bulletins the actual value of any fer- tilizer may be readily estimated if the market price of the "essential ingredients" is known. REFERENCES: I, pp. 22-26; II, pp. 81-85; III, pp. 55-63; IV. pp. 99-104; V, pp. 110-112; VI, pp. 48-49; VII, pp. 129-131; VIII, pp. 131-137; X, pp. 51-53; XIII, 184-242. A Phosphate Problem for Illinois Larxdowners, University of Ills., Agricultural Experiment Station, Circular I 30. Shall We Use Complete Fertilizer in the Corn Belt? University of Ills., Agricultural Experiment Station, Circular 1 65. EXERCISE 20 HOME MIXING OF FERTILIZERS EXPLANATION: In the previous study of commercial fertilizers a difference was found between the dealer's price and the actual value of plant foods contained in the mixture. When this difference seems to be too great the ingredients may be bought separately and mixed at home. When several farmers club together and buy the separate ingredients in quantity a considerable saving may be made. Nitrogen, phosphoric acid, and potash should be bought in concentrated form. For example, phosphoric acid in an acid phosphate having 1 2 per cent phosphoric acid, costs about 7 cents a pound, while in acid phosphate having I 6 per cent phosphoric acid it costs a fraction over 5 cents a pound. The amount of each ingredient desired should be accurately calculated before mixing. DIRECTIONS: All calculations are based upon the percentages of nitrogen, phosphoric acid, and potash in the ma- terials purchased. The following are the percentages of the most common forms of fertilizing materia!^: nitrate of soda, 16 per cent nitrogen; sulfate of ammonia, 20 per cent nitrogen; dried blood, 10 per cent nitrogen; acid phosphate 1 4 to 16 per cent phosphoric acid (the guaranteed analysis will give the exact percentage) ; muriate of potash, 50 per cent potash (the guaranteed analysis will give the percentage of potash in other forms of potash). The amount of nitrogen in a ton (2000 pounds) of nitrate of soda is found by taking 16 per cent of 2000. (2000X- 1 6^320). A ton of nitrate of soda will therefore contain 320 pounds of nitrogen. If a ton of a mixture containing 2 per cent of nitrogen is wanted the quantity of nitrate of soda needed to furnish this amount of nitrogen (2 per cent) may be found as follows: A ton (2000 pounds) containing 2 per cent of nitrogen will have 2 per cent of 2000 (2000X-02=40), or 40 pounds of nitrogen. Since nitrate of soda contains 1 6 per cent nitrogen, one pound of nitrate of soda will contain .16 of a pound of nitrogen (lX-16^.16). Therefore as many pounds of nitrate of soda will be re- quired to furnish 40 pounds of nitrogen as .16 is contained in 40 (40-^.16=250), or 250 pounds. Similar calculations can be made of phosphoric acid and of potash by substituting 14 per cent for phosphoric acid and 50 per cent for potash. Suppose a ton of a 4-8-3 fertilizer is to be made, how much nitrate of soda, acid phosphate, and muriate of potash will be needed? First find the number of pwunds of nitrogen, phosphoric acid, and pot- ash in a ton of a 4-8-3 fertilizer: 2000X.04=80, or 80 pounds of nitrogen. 2000X-08=1 60, or 160 pounds of phosphoric acid. 2000X.03=60, or 60 pounds of potash. Next find the amounts of nitrate of soda, acid phosphate, and muriate of potash necessary to fur- nish the required number of pounds of nitrogen, phosphoric acid, and potash: 80-!-. 1 6^500, or 500 pounds of nitrate of soda needed to furnish 80 praunds of nitrogen. 160-h.l4=l 142.8, or 1 142.8 pounds of acid phosphate needed to furnish 160 pounds of phos- phoric acid. 60h-.50^I20, or 120 pounds of muriate of potash needed to furnish 60 pounds of potash. The cost of such a mixture may be easily found by using the following (average market price for 1913): Nitrate of soda $57.50 per ton; phosphoric acid ( 1 4 per cent phosphoric acid) $1 6.00 per ton; muriate of potash $42.00 per ton. Find value of each material per pound and multiply by total number of pounds desired: At $57.50 per ton, one pound of nitrate of soda will cost 2.875 cents (57.50x100-^2000= 2.875). 500 pounds will cost $14,375 (500x.02875=I4.375). At $16.00 per ton, one pound of acid phosphate will cost .8 cent ( I 6X 100-^2000=. 8) 1 142.8 pounds will cost $9.14 (1142.5X.008=9.I4). At $42.00 per ton one pound of muriate of potash will cost 2.1 cents (42x100-^2000=2.1). 120 pounds will cost $2.52 (120X.02 1=2.52). The total cost of materials to prepare one ton of a 4-8-3 fertilizer will be $26,035 (14.375-|- 9. 1 4_|_2.52=:26.035). The total number of pounds of material needed to make a ton of a 4-8-3 fertilizer will be 1762.8. Therefore 237.2 pounds of filler must be added to bring the mixture up to 2000 pounds (2000 — 1 762.8:=237.2). In farm practice, however, the fertilizer may be applied at a correspondingly lower rate per acre. In this case about % of the desired rate should be applied thus sav- ing the trouble of adding a filler. Problems. 1. How many pounds of nitrogen are in one-half ton of nitrate of soda? In one-half ton of dried blood? Of sulfate of ammonia? 2. How many pounds of phosphoric acid in one and one-half tons of acid phosphate containing 14 per cent phosphoric acid? Containing 16 per cent phosphoric acid? 3. How many pounds of potash in three-quarters of a ton of muriate of potash? In the same amount of kainit containing 12 per cent potash? 4. How much each of nitrate of soda, acid phosphate (containing 14 per cent phosphoric acid), and muriate of potash will be required to make a ton of a 1-9-4 fertilizer? How much filler will be needed? Estimate total cost based upon $57.50 per ton for nitrate of soda, $16.00 per ton for acid phos- phate, and $42.00 per ton for muriate of potash. 5. Wheat straw contains .6 per cent of nitrogen. What would be the loss in pounds of nitrogen in burning 50 tons of wheat straw? Calculate the loss in dollars and cents if nitrogen is worth 19 cents per pound. 6. Manure on the average contains .5 per cent of nitrogen. Calculate the value of the nitrogen in 140 tons of manure. 7. The average loss of nitrogen by leaching when manure is in unprotected piles for two months or more is 50 per cent. What would be the value of nitrogen lost in 140 tons of manure kept under such conditions? 8. Phosphoric acid in rock phosphate is not immediately available for plant growth, but may be made gradually available by mixing with manure. Rock phosphate containing 1 2 per cent phosphoric acid may be purchased (including freight) for $8.00 per ton. How much can be saved in cost per pound of phosphoric acid in applying phosphate in this way compared with use of acid phosphate (14 per cent phosphoric acid) at $16.00 per ton? APPLICATION: The foregoing problems illustrate the application of simple arithmetic in calculating amounts of fertilizer ingredients and in estimating comparative values of fertilizers. Home mixing may be easily done with a scoop shovel on a tight barn floor. The calculated amount, by weight, of each ingredient is piled on the floor and uniformly mixed with the others. The waste of nitrogen by improper treatment of straw and manures is shown in problems 5, 6 and 7. These materials also have much value in improving soil texture by adding humus to the soil, and by furnishing organic material for action of soil bacteria. Problem 8 suggests a further saving by making use of rock phosphate, a much cheaper means of supplying phosphoric acid than by use of acid phos- phate. In most soils, except very sandy soils, there is a sufficient store of potash for most crops. A reasonable farm practice in keeping up soil fertility would be to provide nitrogen, the most ex- pensive plant food (costing about 19 cents a pound when bought), by use of manures and straw, and by rotation of crops with legumes (clover and the like) ; to liberate phosphoric acid by mixing ground phosphate rock or bone meal with manures ; and to add potash for special crops only. Sometimes a complete fertilizer may be needed. In such cases home mixing is often more economical than the pur- chase of materials already mixed. REFERENCES: II. pp. 357-359; V. p. 112; VII, p. 131 ; XIII. pp. 209-219. EXERCISE 21 A STUDY OF WEEDS EXPLANATION: Everyone is more or less familiar with plants called weeds. These plants get in the way of culti- vated crops; they rob the soil of moisture and plant food; they are often unsightly; altogether they are very undesirable. But they are successful plants for they grow everywhere, and often in places where cultivated plants would not thrive or grow at all. The weed's success in growing almost any place, in crowding out and otherwise interfering with the growth of cultivated plants, makes it worthy of careful study. First of all, the common weeds should be known at sight. How many weeds are to be found in the yard, on the roadside, or in the garden, and what are their names? Which ones are the most trouble- some? Why are some weeds greater pests than others? How are they able to spread so rapidly? How do they scatter their seeds? These are some of the questions that should be answered in a study of weeds. DIRECTIONS: Idenl'ification of Weeds and Seed Collection. In order to know the common weeds by their right names it is necessary to consult some xeeed manual. Collect a few weeds and look for their descriptions in the manual. If the common name is known look for this name in the index and turn to the description to verify it. If the common name is not known it will be necessary to hunt a description that will fit the plant. This is made easier by the illustrations accompanying the descriptions of many of the weeds. The name may be further verified by comparing the seed of the weed with the seed picture in the manual. When the weed is properly identified some of its seeds should be put in an envelope or folded in a piece of paper, and the name of the seed written on the outside. After all the common weeds have been identified, their seeds collected and properly labeled, the seeds may be placed in small vials and labeled. A good collection of weed seeds will give valuable assistance in detecting weed-seed adulteration of commercial seeds like wheat, clover and alfalfa. Rale of Increase. One reason for a weed's success is its rapid rate of increase. If any common, troublesome weed be studied when its seeds are ripe a great many seeds will be found. Select a weed and estimate the number of seeds it bears. This may be done by finding the number of seeds in one branch, then the number of branches and multiplying them together. Measure the space occupied by a weed, taking the diameter of the space shaded at noon as a basis. Find the space which would be occupied by plants the second year if each seed should produce a plant the size of the parent plant. At this rate how many seeds will be produced the second year? If each of these seeds produces plants the third year how much space will the plants occupy? How many seeds will be produced the third year? For example, a willow lettuce produced 2435 seeds one year and the plant occupied 105 square inches of space. The space occupied the second year would be 6'/2 square rods, and the third year 99 acres. Seed Dispersal. Not only do weeds produce large numbers of seeds, but provision is made for scattering the seeds. Seeds are scattered by means of the wind or animals. Some seeds, like dandelion, milk weed, and white top, are light and provided with hairs or wings to catch the wind. Others which are scattered by animals, are either provided with hooks or barbs which adhere to the animal's body, or with food, such as nuts or fruits, which attracts the animal. Spanish needle and cockle burr are examples of the former and poison ivy of the latter. Seeds are also scattered by wagons, trains and impure commercial seeds. Make lists of seeds scattered by each method and study the various means or devices for transportation. APPLICATION: Two valuable lessons are suggested in the study of weeds: (1) that the common weeds should be known by sight even when young, so that the most troublesome kinds may be recognized and destroyed early in the growing season; (2) that great numbers of seeds are produced and in many instances with special provision for scattering them. Hence the importance of destroying the weed before the seed ripens. REFERENCES: I. pp. 73-76; II, pp. 29-32; IV, pp. 201-207; VI. pp. 7 1-77; VII, pp. 70, 244-247; VII, pp. 173-178; IX, pp. 43-45, 49-75; X, pp. 118-120. 312-318; XIV, pp. 523-539. Second Ohio Weed Manual, Ohio State Experiment Station. Bulletin 1 75. Seeds of Michigan Weeds, Michigan State Agricultural College. Bulletin 260. Michigan Weeds, Michigan State Agricultural College, Bulletin 267. Weeds of the Miama Valley, Miami University, Bulletin, Series 9, No. 2. SEED ANALYSIS EXERCISE 22 EXPLANATION: Often commercial seeds, especially clover and alfalfa seed, contain weed seed and other impurities. A seed analysis is an examination of a sample of seed to determine the amount and character of the im- purities that may be present. DIRECTIONS: Weigh out an ounce of the seed to be analyzed. Next, thoroughly mix the sample so as to distribute the impurities uniformly; separate into four equal piles. Place the seed of one pile on a piece of white paper and with pencil or finely pointed stick separate the seed into four parts as follows: (1) pure seed, (2) poor seed, (3) dirt, (4) weed seed. After this separation has been made weigh each part and find what per cent this weight is of the pile examined ('/4 ounce). The results may be checked or verified by repeating the separation with one of the remaining piles. If the results do not agree take an average of the two. Arrange the final results in form of a tabulation, for example: Sample Pure Seed Poor Seed Dirt Weed Seed No. 1 91 per cent 6 per cent 1 per cent 2 per cent No. 2 85 per cent 1 per cent 2 per cent 3 per cent No. 3 94 per cent 5 per cent per cent 1 per cent Finally, identify and make list of the kinds of weed seed found. The work of identification will be made easier by referring to seed collection made in the previous exercise. APPLICATION: Commercial seeds are graded according to the impurities they contain. Low grade seeds are really more expensive than high grade. For example: If one kind of seed containing 95 per cent, pure seed sells for $15.00 per bushel, and another containing 70 per cent, pure seed sells for $12.00, which is the cheaper? In this case the $15.00 seed sells at the rate of $15.78 (15x100^95=15.78) per bushel of pure seed; while the $12.00 seed sells at the rate of $17.14 (12x100^70=17.14) per bushel for pure seed. Not only are low grade seeds usually more expensive because of the lower percentage of good seed which they contain, but also on account of the weed seed which may develop into troublesome pests in the field. Freedom from weed seed is especially important in alfalfa seed, for nothing interferes so much as weeds in getting a stand of alfalfa. Examine a number of samples of commercial seeds in the local market and determine the cost of pure seed in each sample at the rate of the dealer's selling price. REFERENCES: I, pp. 77-80; II, pp. 24-28; V, p. 152; VII, pp. 51-53; IX, pp. 46-47; X. p. 69. Second Ohio Weed Manual, Ohio State Agricultural Experiment Station, Bulletin 1 75. Seeds of Michigan Weeds, Michigan State Agricultural College, Bulletin 260. EXERCISE 23 LIFE-HISTORY OF INSECTS EXPLANATION: Insects are either injurious or beneficial according to whether they hinder or help man in his work. It is important to know all we can about insects in order, if they are injurious, to reduce their numbers or to assist their natural enemies (other insects, birds, toads, etc.) ; or, if they are useful, to help and en- courage them. The chief facts to be observed in the study of insects are: Where they live, habitat; how they live, habits; how they develop and grow, life-history. By life-history is meant the various stages through which an insect passes during its entire life. Most insects pass through four stages: egg, larva (caterpillar of the butterfly and moth, maggot of the fly, grub of the beetle, etc.), pupa (resting or inactive stage, called cocoon if pupa is encased in covering of silk), and adult. Some insects, like the grasshopper, pass from the egg directly into a stage called nymph. The nymph is like the adult except in size and proportion of parts and in absence of wings. Life-history studies of insects should begin with some very common and familiar insect, for example, the cabbage butterfly, and after the method of study is learned it may be applied to any kind. DIRECTIONS: In general, a life-history study should begin with the most familiar stage. This is usually the larva. The following directions for study of the life-history of the cabbage butterfly may be followed in the study of other insects: Collection of specimens of ihe larvae. TTie dark green worms nearly always found on cabbage plants are the larvae of the cabbage butterfly. A few leaves of the cabbage should be brought in with the worms. Care of the larvae (caterpillars) . Insect larvae should always be provided with fresh food of the same kind which they are found upon. Some kind of a cage must be provided to keep the insects from crawling away. A large mason jar covered with mosquito netting or cheese cloth held in place with a string or rubber band will do. Change from larva to pupa. The caterpillars should be observed from time to time. Among the points to observe are manner of eating; how much is eaten in a given time — say ten minutes; time of eating, whether continuously or not; manner of crawling; moulting or shedding skin. When the larva grows to about an inch in length it will cease eating and perhaps crawl up the side of the cage where it will fasten itself by means of a band of silk thread. This is the beginning of the change from the larva into the pupa. The shape of the body will then be changed, and finally the outer covering will be transformed from a soft, smooth to a rough, hard coat. This stage is the pupa. The insect remains in this stage for a few weeks. Eggs. While the larvae are being kept in confinement, a search should be made for eggs of the butterfly. They are found singly or in clusters on the under side of the cabbage leaf. They are just large enough to be seen, oblong in shape, and pale yellow in color. When found, each egg and the piece of leaf to which it is attached should be placed in a glass tumbler. In a few days, sometimes in a few hours, the egg will hatch into a tiny worm which will soon begin to eat the leaf. The rate of develop- ment from the beginning to end of the larval period depends upon food and warmth — rapid, if well supplied vnlh fresh food and kept warm — slow under contrary conditions. Adult — the butterfly. While the pupa remains suspended and apparently lifeless great changes are going on inside its case. When these changes are complete the pupa case breaks and the butterfly appears. If the butterflies which have emerged from several pupae are observed they will be found to be of two kinds — male and female — the male with one black spot on each fore \v'..^.z, t'.ie female with two. OutJoor ohservaiions. All four stages should be observed in the garden. With some practice it will be easy to find eggs and pupae. Butterflies of both sexes may be seen flying about. Look for natural enemies. Are the larvae and butterflies caught by birds? Look for parasitised caterpillars. Some cater- pillars are killed by the larvae of a little fly. Collect a number of dead caterpillars and keep them in a covered glass tumbler. Usually the larvae of the fly will break through the skin of the caterpillar and pass into the pupa stage; later each pupa will produce a little fly. A fly of this kind lays its eggs in the egg of the cabbage butterfly. The eggs of both insects hatch, but the larvae of the fly in some way gets into the body of the caterpillar where they use its blood for food and finally cause its death. One insect living ofl^ another is called a parasite. Insects which are parasites on injurious insects are good illustrations of beneficial insects. APPLICATION: Other insects may be studied in a way similar to that described for study of the life-history of the cabbage butterfly. It is not always possible to obtain all stages, but usually two or three stages may be found and studied. In Exercise 24, several insects are suggested for further study. REFERENCES: L pp, 118-125; II, pp. 204-207; III, p. 189; IV, pp. 208-214; V. p. 294; VI, pp. 78-79; VII, pp. 256-257; VIII. p. 179; X. pp. 112-113; XI, pp. 136-139. The Imported Cabbage Worm, U. S. Departnrient of Agriculture, Bureau of Entomology, Circular 60. EXERCISE 24 SOME COMMON INSECTS FOR LIFE-HISTORY STUDY EXPLANATION: In order to secure a wider acquaintance with life-histories of insects, and especially to learn to apply methods of study, some or all of the insects suggested in this exercise should be studied. DIRECTIONS: Brief suggestions are given for the study of each insect. Accounts of each insect studied should be looked up in the references at end of exercise. Careful notes should be taken of everything found in the study of each insect, for example, where and when found, how taken care of while under observation, manner of eating, date of formation of pupa, date of appearance of adult, etc. Tomato Worm. Tomato worms are the larvae of the large moth called sphynx moth. Collect several large worms and put in a box half full of moist earth. Keep the worms supplied with fresh tomato leaves. Observe manner of eating and amount of food consumed. In a short time, perhaps within a week, the worms will burrow into the earth and change into pupae. After examining the pupae bury them again, and remove the box where the earth will be kept cool and moist. In the early spring bring the box into a warm room. After several days of warmth the moths will appear. In order to prevent moths from flying away the box should have a covering of glass or mosquito netting. Corn Worm. The caterpillars are quite common in the fall under the husks of ears of corn, es- pecially of sweet corn. To get the pupae prepare a box by filling half full of field soil, and then lay on top of the soil a few ears of corn infected with corn worms. The box should be covered to prevent escape of worms. Later the worms will leave the corn and burrow into the earth where they will transform into pupae. After examining the pupae bury them again and proceed as directed for the tomato worm. Codling Moth or Apple Worm. The larvae of this insect are the worms found in wormy apples. They may also be found under the flakes of bark of an apple tree, where they spend the winter in loose mats of silk. In the spring the larvae change to pupae, and in a few weeks, moths emerge. The moths lay eggs on young apples about the time the petals drop off. The eggs are very small and rather hard to find. They are flat, whitish objects clinging close to surface of the apple, in appearance somewhat like small fish scales. Remove some worms from an apple or from underneath the bark of an apple tree. Put each worm in a small vial and cork lightly. The larva will eat away the cork on one side and form a web of silk where it will remain for the winter. In the spring, or sooner if kept in a warm room, the larva will transform into the pupa, and in a short time the moth will appear. Thus three stages of the codling moth may be seen without removing the cork from the bottle. Plum CurcuUo. The larvae of this insect are about as common as the codling moth larvae. Many green plums that have fallen to the ground contain worms. These worms are the larvae of a beetle called plum curculio. Gather a number of wormy plums and put into a mason jar half full of moist earth. Each larva will burrow into the earth and there pass into the pupa. Later the adult will emerge. It is a rough-winged beetle with a long snout. By means of its long snout or proboscis it makes a hole in the plum in which it deposits an egg. Sometimes the beetles may be obtained by spreading a newspaper under a plum tree and then shaking the tree. Usually several beetles will fall upon the paper. Scale insects. The oyster-shell scale (so called because of its oyster-shell shape) is common on poplar, Cottonwood and ash trees. Collect pieces of bark or twigs covered with these insects. In the fall or winter eggs may be found by lifting a scale with the point of a pin. They are very small and white in color. Count the number of eggs found under one scale. In the spring the eggs hatch. If noticed early enough the young will be found under the parent scale. Later they may be seen as tiny yellowish insects running about among the adult scales. The San Jose scale is smaller than the oyster-shell scale. Its shape is round with the center elevated into a small peak. This scale is found on a great variety of trees and shrubs, but is most common on osage-orange, apple, pear, plum, peach and Japanese plum. The young are produced alive. They are very small, but may easily be seen by use of a lens. Three generations are produced in a season so that young may be found from early summer until early fall. If one San Jose scale produces 200 young, 100 of vi^hich will in turn produce 200 young, there will be 20,000 in the second generation; and if one-half of these reproduce at the same rate there will be 2,000,000 in the third generation. The reproductive capacity of the San Jose scale accounts for the great amount of damage it does to fruit trees. The insect makes up in numbers for what it lacks in size. APPLICATION: These studies furnish a basis for further study and reading. The habit of trying to work out life- histories of insects should be formed. Text-books and other references will give helpful suggestions. The mosquito, house fly, plant lice, Colorado potato beetle, clothes moth, cabbage looper, woolly bear and currant worm are examples of insects whose life-histories are easy to study. A loan collection of common insects may be secured from Miami University, Oxford, Ohio. This collection will be helpful in identifying insects. REFERENCES: I. pp. 126-146; II. pp. 208-222; III. pp. 190-199; V, pp. 295-321; VI. pp. 80-84; VIII. pp. 181-185; X, pp. 113-114; XI. Fall Manual of Economic Zoology, Ohio State Agricultural Experiment Station, Bulletin 164. Winter Manual of Economic Zoology, Ibid., Bulletin 233. Spring Manual of Economic Zoolog}), Ibid., Bulletin 198. Horse Flies, U. S. Department of Agriculture, Farmers' Bulletin 459. Common White Grubs, Ibid.. Farmers' Bulletin 543. The Army Worm, U. S. Department of Agriculture, Bureau of Entomology, Circular 4. Plum Curculio, Ibid., Circular 73. Oyster Shell Scale and Scurvy Scale, Ibid., Circular 124. San Jose Scale and its Control, Ibid., Circular 124. The Colorado Potato Beetle, Ibid., Circular 87. The Codling Moth or Apple Worm, U. S. Department of Agriculture, Year Book, Reprint 1907. EXERCISE 25 RELATION OF BIRDS TO INSECTS EXPLANATION: Insects because of their large number, rapid rate of increase, and great eating capacity are able to do much damage to trees and crops. Every native and cultivated plant has its insect enemies. TTie apple tree is injured by more than 200 kinds, corn by more than 250. Forest trees are not free from injury. The oak feeds more than 500 species, the elm at least 1 00, the poplar 260, the willow nearly 400 and other trees from 1 00 to 300. Insects have two important natural enemies: other insects, chiefly as parasites, and birds. Birds are especially well fitted for destroying insects. They fly easily and swiftly from place to place. They also consume much food. Some birds are able to digest as many as ten full meals per day. Young birds require food that is easily digested. Insects, especially in the larval stage, are the favorite food for young birds. A young robin has been known to eat half its own weight in insects in one day. In view of the great value of birds as insect destroyers, bird-study should receive attention in every school. Such a study should be of birds and not about them. DIRECTIONS: Recognition Study. This should begin in the winter when there are but few kinds of birds. About fifteen species are common in the winter; downy woodpecker, hairy woodpecker, brown creeper, nuthatch, tufted tit-mouse, chick-a-dee, blue jay, cardinal, winter wren, Carolina wren, quail, tree sparrow, English sparrow, crow, and junco, or snow bird. Early in the spring, sometimes in February, migratory birds will begin to return. Gradually all the summer residents will appear, and many migrants on their way north may also be seen. A list should be kept of the birds as they return, giving the date when first seen and when common. TTie "Bird Guide" referred to at end of this exercise should be consulted when the identity of any bird is in doubt. Attracting birds. During the winter birds may be encouraged to come about the home or school by providing them with food. Tie soup-bones or pieces of suet to the limbs of trees, and fasten a feeding board, on which is kept crumbs and other food, to the outside of a south window. Nearly all winter birds will be attracted in this way, and a good chance will be given for observing them. Accounts should be written from time to time in note book of bird-visits to feeding places. In the spring, nesting material, such as cotton or wool, should be put in forks of trees, and bird houses should be made and set up securely in trees. Relay-study. After a nest of young birds convenient for observation is located, a relay-study should be planned. The work of observation should be divided among several persons, so that each two persons will have a regular turn of one hour or of one-half hour observation. The object of this study is to keep the nest under constant observation for several successive hours. Two persons begin the observation, taking notes of visits of the parent birds to the nest, giving the exact time to the minute (visit 1, 8:11; visit 2, 8:16; visit 3, 8:21, etc.) Note should be taken of other things the birds do, such as catching insects, cleaning nest, singing, etc. At the end of the relay period the first two observers are replaced by two others, and so on as long as the relay continues. After the relay has been completed the notes taken by the various observers should be tabulated, showing time of each bird-visit to the nest, intervals in minutes between visits, total number of visits, visits per hour, and average interval between visits. Method of tabulating notes is illustrated from the following relay study of a pair of wrens: Time No. of Male Visits No. of Female Visits M - 9:20 A. M. — 10:20 A 10:20 • — 11:20 ' 1 1 :20 • — 12:20 ' 12:20 P. M. — 1:20 p. 1:20 • • — 2:20 ' 2:20 • — 3:20 ' 3:20 •• ■ — 4:20 ' 4:20 • • — 5:20 ' 5:20 ' — 6:46 ■ M.. 15 10 6 13 9 1 10 1 5 10 5 9 18 1 91 22 Total number of visits, 113; average, 12 per hour; average interval, 5 minutes. Food brought: cutworms, grasshoppers, cabbage worms, and other kinds not identified. Relay-studies should be made of several kinds of birds and results compared. APPLICATION: In this exercise a few ways are suggested for bird-study. The great lesson is to know the common birds by sight and song, to discover their value from actual observation, and to encourage and protect them in every way possible. REFERENCES: I, pp. 234-240; II. p. 222; III. p. 201 ; IV. p. 210; V. pp. 322-328; VI. pp. 90-98; VIII. pp. 185-187. Some Ohio Birds, Ohio State Agricultural Experiment Station, Bulletin 250. Food of Some lVell-}(nown Birds of Forest, Farm and Garden, U. S. Department of Agri- culture, Farmers* Bulletin 506. Fift\) Common Birds of Farm and Orchard, Ibid., Farmers' Bulletin 513. Bird Guide, Garden City, N. Y. : Doubleday, Page and Co. EXERCISE 26 BLACK MOLD: AN EXAMPLE OF A FUNGUS EXPLANATION: Fungi (singular fungus) are very low in the scale of plant life. They have no leaf-green (chlorophyll) and therefore are not able, as green plants are, to make starch and other foods. TTiey live upon the dead remains of plants and animals or upon living plants or animals. When they live on living plants or animals they are called parasitic fungi. In getting their living from other living plants fungi interfere with the health of the plants on which they live, causing disease. The plants attacked by fungi are called hosts. Thus, corn is the host for the smut fungus; wheat, for the rust fungus, etc. Many of the fungi causing plant diseases are very small and are difficult to study without the use of a microscope. But the essential features of all fungi are similar. These features may be understood by a study of the common black mold. DIRECTIONS: CroTvlh and structure of mold. A growth of black mold may usually be secured in a few days by keeping a piece of moist bread in a warm place (75-95 degs.) in a covered dish or a mason jar. The dish or jar is covered to prevent the bread from getting too dry, for a certain amount of moisture is needed for mold growth. After two or three days a network of silvery white threads will appear on the surface of the bread. A little later certain areas of the network will seem dark or black. If a piece of bread supporting one or more of these areas is removed and examined under a lens, numerous small black balls will be seen on the ends of certain erect mold threads. These balls are called sporangia. Each sporangium contains numerous very small black particles called spores. The threads of the mold together make the mycelium. Many of the threads penetrate the substance of the bread, where they dissolve and absorb food for further growth. Food getting is the chief function of the mycelium. Some threads, however, grow away from the main thread mass and produce spores in the sporangia, and the spores in turn produce new plants. Development of mold from spores. The production of mold from spores may be shown by a simple experiment. Cut a piece of bread to fit a wide mouth bottle. Put a few drops of water in the bottle, then the bread, and plug the mouth of the bottle with cotton. TTie bottle should next be heated in boiling water for one-half hour. Care should be taken to prevent breaking the bottle by rapid heating or rapid cooling. The object of heating is to kill any mold spores that may be on the bread or in the bottle. It is generally safer to heat for one-half hour on three successive days, for sometimes the spores will not all be killed by one heating. The process of killing spores by means of heat is called sterilization. The bread in the bottle thus treated is sterile, or free from living spores. Sterilize the end of a piece of wire by holding it a moment in ihe lire or in the flame of an alcohol lamp. Touch the end of the sterilized wire to black mass on some moldy bread. Many spores will adhere. Remove the cotton from the bottle and scrape the end of the wire over the side of the piece of sterilized bread. Replace the cotton. Keep in a warm place, and in a few days examine for appearance of mold. APPLICATION: Three important facts are to be noticed in this study of black mold: (1) The main body of the mold consists of mycelium or threads, the purpose of which is to secure food; (2) New colonies of mold are formed by means of spores; (3) Spores may be killed by heat. They may also be killed by certain chemicals, as will be seen in another exercise. Other kinds of molds will doubtless have appeared in the first part of the mold study. Some are green, others are bluish green. The coloration is due to the color of spores. The essential features are the same for all molds, viz., a network of mycelium, and later production of spores. REFERENCES: I, pp. 95-96; IV, pp. 215-216; V, pp. 267-270; VII. p. 251 ; VIII. p. 168. Handbook of Diseases of Cultivated Plants, Ohio State Agricultural Experiment Station, Bul- letin 214. EXERCISE 27 POWDERY MILDEW: AN EXAMPLE OF PAFIASITIC FUNGI OR OF PI ANT DISEASE EXPLANATION: In the study of parasitic fungi it should be kept in mind that these fungi are like the bread mold in general structure — both have mycelium for getting food (one from living matter, the other from non- living matter), and both produce spores for developing new fungi. Parasitic fungi are usually not so easily seen and studied as bread mold. Often the mycelium is concealed in the part of the plant on which the fungus is growing. The effect, however, on the plant infested by the fungus may be quite apparent. Often the disease may cause the death of the whole plant attacked. Powdery mildews are common parasitic fungi growing on the leaves of lilac, rose, peach, peas, and other plants. DIRECTIONS: A powdery mildew may be recognized by the white or dirty white appearance of the leaves infected. Collect a number of infected leaves and examine the while coating with a lens. The coating will be seen to consist of a fine network of very small threads, the mycelium. TTie ends of some of the threads are erect, that is, they extend away from the mycelium. The upper portion of each erect branch, when seen with a compound microscope, looks like short strings of beads. Each bead-like body is a spore. The spores give the dust-like appearance to powdery mildew. Later in the season another kind of spore is formed. On the mycelium on some of the leaves may be seen small black specks. These black bodies contain spore cases or spore sacs. The spore sacs are too small to be readily seen with an ordinary lens. But if some of the black bodies are placed upon a microscope slide in a drop of water, covered with a cover-glass, and the cover-glass is then gently pressed, these bodies will be crushed. Examine under com- pound microscope. In the crushed remains of each black body will be seen a number of spore sacs. It is sometimes possible to see the spores as four or more tiny dots within each spore sac. The spores within the spore sacs may be readily seen by using the high power of a compound microscope. Consult description of powdery mildew in special reference. Notice, especially the pictures and compare them with observation made in this study. iVIake list of all plants whose leaves are found attacked by the powdery mildew. Compare plants attacked with those that are free from the disease, noting difference as to vigor, growth, etc. APPLICATION: In the powdery mildew, as in all fungi, a great many spores are produced. Spores are light and easily carried by the wind to other plants, where they germinate and produce new fungi. Spores accumu- late during the growing season and remain alive during the winter. In the spring, when the leaves of the host plants appear, some of the winter spores are carried by the v/ind or by insects to the fresh leaves of the host plants and infection takes place. By burning all of the infected parts of plants in the fall, the infection of new plants or of new growth in plants in the following spring may be greatly lessened. In the case of annual plants like peas, diseases such as mildev/ may be avoided by growing the crop in a new location. Burning infected plants or infected parts of plants, and rotation of crops will not always prevent recurrence of a plant disease during the following year. The number of spores should be further reduced by spraying with some chemical that will destroy the spores or prevent their germination. The use of sprays will be considered in another exercise. REFERENCES: I, pp. 96-98; V. pp. 264-272; VI. p. 87; X, pp. 115-116. Handbook of Diseases of Cultivaled Plants, Ohio State Agricultural Experiment Station, Bul- letin 214. EXERCISE 28 SOME COMMON PARASITIC FUNGI: PLANT DISEASES EXPLANATION: The study of bread mold and of powdery mildew (Ex. 26-27) gives a good idea of the general features of fungi. Detailed study of most parasitic fungi is difficult and requires special training. It is possible, however, to recognize many common plant diseases by noticing the effects produced on host plants. These effects may be regarded as symptoms of disease. They are classified according to the general appearance of the injury, as follows: rot, blight, wilt, leaf-spot, scab, mildew, smut, rust, and canker. TTie object of this exercise is to give some examlples and brief descriptions of common plant diseases that will help in their recognition. DIRECTIONS: Rot. The name itself suggests the nature of the injury caused by this class of diseases. Fleshy parts of a plant are most often affected, although the injury is found on other parts of some plants. Examples: Bilier Rot of the Apple. It appears, at first, on the fruit as small, round, rotten spots. Later the spot becomes dry and dark colored. The spot increases in diameter gradually, involving the entire fruit. The surface becomes wrinkled, and, toward the center of the rotten area, small elevations (pustules) bearing spxires appear. This disease is most noticeable about the time the fruit begins to ripen. Brown Rot. This is a common injury of the peach, plum and cherry. The fungus attacks the fruit as it approaches maturity, first appearing as a round, dark spot and gradually extending over the entire fruit. As decay advances small bunches of brown threads appear, at first near the center of the original spot, and rapidly extended until the whole fruit is covered. If the infected fruit remains on the tree it shrivels up into what is known as "mummy fruit," and may hang there during the winter. On exam- ination of "mummy fruits" some will be found bearing small mushroom-like bodies. These bodies beatf spores which may start a new infection. Black Rot. This rot attacks grapes. It begins as dark purple spots, which gradually involve the whole grape. Later the grape shrivels up and turns black. Blight: This name is applied to injuries to leaves and other parts of plants where the parts infected become dead. Examples: Fire Blight. TTiis is a disease caused by bacteria. Although bacteria are not true fungi, they are like the fungi in their food requirements, and some cause injuries similar to those made by parasitic fungi. Fire blight attacks the leaves and twigs of apple and pear trees, causing them to shrivel and blacken as if burned. The leaves of the diseased twigs do not fall as do the leaves of healthy twigs. This fact makes it possible to recognize the blight in winter. In the spring the diseased twigs way be recognized by their dead black leaves. A similar bacterial disease is common on the tomato and is sometimes known as tomato wilt. Lettuce and beans may be attacked by blights that are caused by the growth of true fungi. The lettuce blight appears on the outer leaves. Finally the entire plant is affected and dies, especially late in the season. The bean blight appears on the leaves and pods as large watery blotches. Earl^ blight and late blight are two destructive diseases of the potato. Both make their first appearance on the leaves, the former early in the season as brown leaf-spots, the latter late in the season on the margin of the leaves, gradually spreading over the rest of the plant causing its death. Mildew. See Exercise 27. Wilt: The name indicates the character of the injury. The roots or parts of the stem are in- jured, thus cutting off the water supply from the leaves and upper parts of the plant, causing them to wilt. Examples : Sweet Potato Wilt (sometimes called stem rot). Here the stem is injured, causing the wilting and final death of the vine and leaves. Leaf Spots: Many spots on leaves are made by the fungi injuring small areas. Examples: Leaf Spot of apple, bean, beet, cherry, clover, strawberry, pea, pear, and tomato.. Scab: In this class of diseases the surface of the part infected is thickened and roughened. Examples: Apple Scab affects leaves and fruit. On the fruit the scab appears first as an olive green area. Later the fungus breaks through the skin, forming a dark, rough, circular spot. Peach Scab appears first as black spots, which enlarge into rough blotches. These blotches fre- quently extend over half or more of the fruit. Smut: Parasitic fungi producing masses of black powdery spores are called smuts. Examples: Corn, wheat, oats and barley are frequently affected by smuts. The appearance is too well known to require further description. Rust: The rust fungi break the surface of the host plant and form a large number of spores. These spores, in some cases, resemble iron rust in appearance— hence the name. Examples: Rusts of Tvheat. In the early part of the season red or orange rust is common, appearing as streaks on the stems and leaves. Late in the season the spores are black. This stage is known as the black rust. Both red and black rusts of wheat are different stages of the same kind of fungus. The rusts of oats and barley are similar to wheat rust. Canker: When the disease causes splitting or roughening of the bark of tree trunks or limbs, the injury is called canker. Examples: Apple Canker. The fungus causing bitter rot sometimes extends to the twigs or larger branches, forming cankers. Another canker of the apple extends to the twigs and branches from a disease of the leaf known as apple blotch. In the latter case the bark becomes cracked and roughened. APPLICATION: It is impossible in the space of a single exercise to give more than a suggestive outline of plant diseases. As many as possible of the diseases mentioned should be studied. Specimens of infected parts should be collected and examined closely. These observations should be compared with descriptions and illustrations in the special references. Recognition- study of plant diseases should be extended to others not mentioned in this exercise, but which are described in the references. A school collection of all the common plant diseases of the school neighborhood should be made. If there is difficulty in identifying any particular disease send a specimen to the State Experiment Station for identification. REFERENCES: I. pp. 94. 102. 103-11 7; H, pp. 225-233; III, pp. 207-210; V. pp. 272-291 ; VI, pp. 85-88; VII, pp. 252-254; VIII, pp. 170-173. Handbook of Diseases of Cultivated Plants, Ohio State Agricultural Experiment Station, Bul- letin 214. EXERCISE 29 CONTROL OF PLANT DISEASES BY SPRAYING EXPLANATION: Since plant diseases are spread by means of spores it is important that the spores be destroyed, and thus check the spread of the disease. This may be done ( 1 ) by burning, (2) by rotation of crops (spores being prevented in this way from reaching host plants), (3) by use of chemicals. The first and second of these methods have already been considered in previous exercises. The third method is based upon the fact that certain chemicals kill the spores of parasitic fungi. The chemicals are usually applied in the form of a spray and are know^n as spray mixtures. A spray mixture which controls plant diseases is called a fungicide; one which destroys insects is called an insecticide. The object of this exercise is to present methods for preparation of the most im|X)rtant spray mixtures. DIRECTIONS: Standard Bordeaux Mixture. This mixture has the following proportion of parts: Copper sulfate (blue vitriol) 4 pounds Unslaked lime 4 pounds Water 50 gallons Preparation: Malerials: Copper sulfate, unslaked lime, wafer, two one-quart mason jars, one gallon pail. Calculation: Since the proportion of the mixture is 4 pounds each of sulfur and lime to 50 gallons of water, any quantity may be made by observing this proportion. If a small amount, say 100 ounces (6'/^ pints), is to be prepared, the calculation may be made in the form of a simple proportion after reducing all the terms to ounces: 64 : 6400 :: X : 100. X represents the number of ounces each of copper sulfate and lime needed. Here its value is I. Mixing: Weigh out 1 ounce each of copper sulfate and of lime. Place copper sulfate in one mason jar and lime in the other, then add 25 ounces of water to each (one pint of water amounts to 16 ounces). Cover and shake until the copper sulfate is completely dissolved and the lime thoroughly mixed with the water. When this is accomplished slowly pour the two together into the pail; or better, pour a little of each into the pail and then stir, repeating until all has been transferred from the mason jars. Now add 50 ounces of water which will complete the 100 ounces of solution. If properly prepared the mixture will have a deep blue color. LIME AND SULFUR MIXTURE. This mixture is not only a good fungicide but a good insecticide as well. It is especially useful in destroying San Jose scale. The proportions are as follows: Unslaked lime _ 20 pounds Sulfur (powder) 1 5 p>ounds Water 50 gallons Preparation: Malerials: Unslaked lime, sulfur, water, a quart tin-can or cup, a gallon pail, some means for heating (an alcohol lamp or oil stove). Calculation: Calculations for any amount may be made by observing the above proportion. If 100 ounces are to be made, the proportion for lime will be 320 : 6400 :: X : 100; for sulfur, 240 : 6400 :: X : 100 or 5 ounces of lime 3^ ounces of sulfur. Mixing: After weighing out the calculated amounts of lime and sulfur slake the lime with 10 ounces of hot water. Then add sulfur and stir until thoroughly mixed. Boil this mixture in a tin can or cup in order to dissolve the sulfur. After the sulfur has been thoroughly dissolved strain through a cloth and add 90 ounces of water to bring the amount up to 100 ounces. If properly prepared the mixture will be a deep reddish-brown color. Bordeaux-Arsenate of Lead. Sometimes it is desirable to apply an insecticide with a Bordeaux mixture, thus destroying insects as well as spores of parasitic fungi. A good combination is one with arsenate of lead at the rate of 3 pounds to 50 gallons of Bordeaux mixture. Formaldehyde or Formalin. This substance is a very effective agent for treatment of some plant diseases. It is not used as a spray but as a wash, for example, on potatoes before planting to destroy spores of late blight, on oats before sowing to destroy the spores of loose smut. The usual strength is one ounce of formaldehyde (40 per cent solution) to three gallons of water. APPLICATION: The above methods should be carried out in small amounts in order to learn the details of prepara- tion. Larger quantides of spraying material may be made by observing the proper proportion of mgre- dients. Details as to methods and time for spraying may be found in special references. REFERENCES: I. pp. 102-103. 319-322: II. pp. 233-236; III, pp. 202-205, 211-212; IV. pp. 218-220; V. pp. 276-280; VI. p. 88; VII. pp. 260-266; VIII, pp. 172, 180-181 ; X, pp. 116. 318-325; XI. pp. 43-48. Handbook of Diseases of CuUivaled Planls, Ohio State Agricultural Experiment Station. Bul- letin 214. Fungicides, U. S. Department of Agriculture, Farmers' Bulletin 243. EXERCISE 30 CARE OF AN APPLE TREE EXPLANATION: Practical application of some of the facts studied in the exercises on insects and on plant diseases may be demonstrated in the care of an apple or pear tree. Little or no attention is usually given to the care of fruit trees, particularly apple trees of the yard or small orchard. The result of this negligence is a low yield and inferior fruit. The value of pruning and of controlling insect pests and parasitic fungi can be illustrated in no better way than by applying proper treatment to one tree, then comparing its yield and quality of fruit with that of neglected trees of the same kind. DIRECTIONS: Selection of tree for the experiment. If possible, select a tree of nearly the same size, age, and variety as another tree in the yard or orchard. This is important to check up results by comparison. Pruning. The object of pruning is two- fold: ( 1 ) to remove dead and diseased branches, (2) to open up the top of the tree to sunlight. The rule for the latter is to cut away the branches so that no branch will cross another, or be shaded by leaves of other branches. The leaves of every part of the tree should receive sunlight at sometime during the day. Branches should be cut off even with the trunk or with the large branch from which they extend. When the branch to be pruned is large, it should first be cut off about one foot from where it originates. In doing this it should be cut half way through from below, and the rest of the cut made from above. The stub can then be cut off even with the trunk or main branch. In order to prevent the infection of the wounds by parasitic fungi the cut surfaces should be painted with coal tar. All the dead branches and twigs should be burned. Pruning should take place while the tree is dormant during the latter part of winter or spring. All pruning should take place before spraying. Spra})ing. Provide a good bucket spraying outfit supplied with a well-made pump and nozzle that will produce a fine mist, two sections of hose (7 and 12 feet) and an extension rod to reach the high parts of the tree. A Vermorel, self cleaning, or disc nozzle works well with such an outfit. The spraying apparatus, particularly the pump and nozzle, should be thoroughly cleaned after using. Winter Spraying. Use the lime-sulfur mixture. The object of spraying at this time is to kill scale and other small insects, and, at the same time, to destroy spores of fungi. A good time to apply this spray is soon after the tree has been pruned. The solution should be freshly prepared according to method given in previous exercise. It may be bought already prepared; for example, the Rex lime-sulfur spray, which must be diluted at the rate of one gallon to ten gallons of water. In the use of the lime-sulfur spray it is important to cover all parts of the tree with a thin layer of the solution without much dripping. Spring Spraying. The Bordeaux-arsenate of lead mixture should be used, the Bordeaux mixture as a fungicide, and the arsenate of lead as an insecticide to kill codling moth larvae. The spray should be applied as soon as the blossoms fall. All the young apples should be reached by the spray. When the newly hatched larvae of the codling moth are eating their way into the apple they get some of the arsenate of lead and are killed. A second spraying should be made from seven to ten days later, and a third between the 10th and 20th of July, depending upon season and location. The third spraying is for the purpose of killing codling moth larvae of the second generation. APPLICATION: At the end of the season when the apples are harvested, separate the good from the poor fruit obtained from this tree, and do the same with the fruit from an untreated tree of the same size and kmd. Compare the results in the total yield of both trees and in the proportion of good to bad fruit. Estimate the value of the fruit from each of the two trees. A further study of the value of spraying may be made by comparing the yield of orchards that have been well sprayed with the yield of those unsprayed. REFERENCES: I. pp. 126-130;II. pp. 234-235; VI. pp. 150-157; VII. pp. 228-233; VIII. p. 218-219; IX. pp. 304-307. The More Important Insect and Fungous Enemies of the Fruit and Foliage of the Apple, U. S. Department of Agriculture. Farmers' Bulletin 492. The Pear and Hoxv to Crow It, Ibid., Farmers' Bulletin 482. The Apple and HoTv to Crow It, Ibid., Farmers' Bulletin 1 1 3. EXERCISE 31 SCORING AND JUDGING CORN EXPLANATION: The most important step in corn improvement is to secure good seed corn. Therefore some basis must be found for determining whether one ear is betier than another for seed. It is impossible to do this by a general comparison of two ears. Comparison must be made with respect to a number of separate characters, each character being valued independently of other characters. Such a procedure is known as scoring. DIRECTIONS: General. Several ten-ear samples of the same type of corn should be provided. Each ear of the sample should be carefully examined with reference to each character, and the value of all the ears of the sample (collectively) with respect to this character estimated in terms of points as indicated on the score card. Cuts. The usual method of making this estimation is by means of cuts. For each deficiency each ear should be cut or reduced in points in proportion to the number of points given on the score card for the character being examined. For example, on "ripeness," (5 points for perfect score) cut off one-half point for each ear that is lacking in this particular; on "condition of germ" (10 points for perfect score) cut one point for each ear. If four ears are deficient in "ripeness" the total value of the sample with reference to this character will be 3. Disqualifications: One or more unquestionably dead ears shall disqualify the exhibit. Exhibits scoring less than 4 out of a total of 10 points on color of grain and of cob shall be disqualified. DIRECTIONS IN DETAIL: Shape of Ear: (5) Varies with variety. In general the ears should be nearly cylindrical. A good rule is "circumference three-fourths the length" — the circumference measured at one-third the length of the ear from the butt. Shape of Kernel: (5) The kernels should narrow gradually from crown to tip. with straight edges that touch full length. The two sides of the kernel facing ends of the ear should be parallel. The "shoe-peg" type of kernel is objectionable. Kernels should vary little in shape as well as in size and indentation, through almost the entire length of the ear. Butt and Tip: (5) The butt should be smoothly rounded over with straight rows of uniform kernels. The shank should not be too large but should have sufficient size to support the ear. The tip should be covered well towards the end with straight rows of uniform kernels. Irregular, shallow or small kernels are more objectionable than tips somewhat exposed. Very tapering tips are ob- jectionable. Color of Cob: (5) Grain free from evidence of mixing shows careful breeding. Cobs of uncertain tints suggest impure breeding. Cut one-half point for each cob entirely off in color. Make other cuts proportionately. Color of Kernels: (5) The same rule holds as for color of cob. Cut one-half point for each badly mixed ear. (An ear with ten or more mixed kernels). Make other cuts proportionately. Viability and Soundness: (25) Of great importance. Seed that will not grow is more than worthless. (A) Condition of Hull: (5) Germination tests show that kernels with blistered hulls will either not grow or are of low vitality — the lack of vitality varying with the degree of blister. (B) Condition of germ: (10) The germ should be bright and oily. A pale, shrunken or dull-looking germ indicates poor vitality. A dark-colored one indicates injury from frost or moisture or from both. (C) Solidity of Ear and of Kernels on Cob, (5) Ears should be firm. In many cases weakness of cob or looseness of kernels on cob indicates lack of vitality. (D) Freedom From Injury: (5) There should be no missing, mouldy, cracked or otherwise injured kernels — the two kernels removed for study ex- cepted. For each ten kernels missing or ruined for seed, cut one-half point. For each 20 kernels slightly injured at crown only, cut one-half point. AJaptahiUi'^: (20) Of great importance in selecting seed corn. Indicated in part by the following: (A) Size of Ear: (10) The standard size of common varieties of dent corn is 10 to 10 J/2 inches in length, and 7J/4 to 7% inches in circumference. A deviation of one-half inch either way is allowed on both length and circumference. If the deviation is greater than one-half inch, cut one- half point for each additional inch variation whether in length or in circumference. (B) Ripeness: (5) An essential quality in corn. Indicated by solidity of kernels, rigidity of cob and firmness of kernels on cob. If immature, the kernels may contain an excess of moisture. Such kernels often lose their tip caps in shelling. (G) Filling of Kernel: (5) Kernels of medium roughness are considered best. The kernel with a chaffy crown ( pinched dent) is indicative of late maturity. Uniformil^: (30) Necessary in all exhibits. Hence the ears and kernels of the exhibit should possess uniform characteristics. Only those characters given in score card under this head need be considered. For purposes of study, two kernels may be removed from one row in each ear between three and four inches from the butt. SCORE CARD FOR CORN CORN Name of Studfnt or Exhibit — Date- Number of Sample or Exhibit SHAPE OF EAR 5 SHAPE OF KERNEL 5 BUTT and TIP .. 5 COLOR OF COB 3 COLOR OF KERNEL 5 VIABILITY & SOUNDNESS (25) Solidity of Ear and of Ker- nels on Cob 5 Freedom from Injury 5 ADAPTABILITY (20) Size of Ear 10 Ripeness 5 Filling of Kernel 5 UNIFORMITY (30) Of Ears Size 10 Of Kernels Size 5 Shape 5 Total, REFERENCES: I, pp. 69-72; II, pp. 132-138; III, p. 77; V. pp. 191-193; VI, pp. 110-113; VII, p. 238; VIII. p. 70; IX, pp. 78-79, 98-10! ; X, pp. 76-78; XIV, pp. 129-132. EXERCISE 32 GERMINATION TESTS FOR SEED CORN EXPLANATION: Although the soundness of an ear of corn may often be determined by close examination of the hulls of kernels, appearance of germs, firmness of kernels on cob, presence of mold, etc., this method is uncertain and should only be applied to the first selection. The ears should be further selected by means of a germination test. Three things are essential in such a test: (I) warmth (60 to 80 degrees), (2) moisture, (3) some provision for keeping the grains of each ear separate, and a system of numbering making grams correspond to the numbers of the ears from which they are taken. DIRECTIONS: Teslor or Cerminator. Make a box 24 inches square and 3 inches deep. Pack the box within one-half inch of the top with moist sand or saw-dust. Cut a piece of white muslin 24 inches square. With an indeliible pencil rule the cloth into 2-inch squares, and then number them from 1 to 144. Another method is, beginning with the upper left hand square to number across the top row, 1 to 12, and down the side, I to 1 2. In the latter method the number of any square is formed by taking corre- sponding square at the side and combining it with a dash or period with the number of the corresponding square at the top. Thus the 6th square in the 7th row would be 7.6, the 9th square in the 1 1th row would be 11.9, etc. This method saves writing so many figures on the cloth. Either method may be used, the main object being accuracy. Lay the cloth on top of the sand or saw-dust and make it per- fectly smooth. Numbering ears of corn. The ears of corn to be tested must be numbered to correspond to the numbers of the squares. There are several methods. One is to number small squares of paper from i to 144 or I.I to 12.12, and then to tack these numbers on the butts of the ears. Another method is to drive a row of nails along the middle of a long plank. The nails should be just far enough apart to form spaces which will admit an ear of corn. The numbers are written on the edge of the plank (1 to 144 or 1.1 to 12.12) and ears put in their places between the nails. When an ear is removed care should be taken to return it to the right place. Filling the tester. Take ear number 1 or 1.1, and with a knife blade pick out two kernels about two inches from the butt; then turn the ear one-third around and remove two kernels from the middle; again, turn the ear one-third and remove two kernels about two inches from the tip. Place the six kernels in square 1 or 1.1. Replace the ear and take No. 2 or 1.2, and proceed in the same manner. Continue until sample kernels are taken from all the ears to be tested. Germination. The box may be covered with glass, or, if this is not available, a cover can be made of a piece of burlap one yard square. Dampen the cloth and carefully lay over the corn. Then spread a half-inch layer of sand or saw-dust over the burlap, folding back the loose ends of the cloth for a cover. Keep the box in a room at a temperature of 60 to 80 degrees. After three days notice the progress of germination. If burlap is used, gently lift the corner of the cover so as not to disturb the kernels. When all the grains of some of the squares have germinated, carefully remove the cover and examine all the squares. Remove the ears corresponding to the numbers of the squares in which more than one kernel fails to germinate. All the rest of the ears may be used for seed corn. APPLICATION: Several testers of this kind could be made, and the school might well undertake to test corn for its patrons. The testing could be arranged so as to interfere but little v/ith the regular school work. It takes as much care and labor to put in and cultivate a poor stand of corn as it does a perfect stand. The trouble of making a germination test of all seed corn planted is repaid many times by the more perfect stand secured and the consequent greater yield. REFERENCES: I. pp. 77-78; II. pp. 138-140; III. pp. 74-76; IV. pp. IKy-in-. V, pp. 151-152; VI. pp. 115- 116; VII. pp. 48-50; VIII. p. 148; IX. pp. 84-85; X. p. 9; XIV. pp. 69-70. Testing Farm Seeds in the Home and in the Rural School, U. S. Department of Agriculture, Farmers' Bulletin 428. Seed Corn, Ibid.. Farmers' Bulletin 415. EXERCISE 33 EAR-TO-ROW TEST FOR SEED CORN EXPLANATION: Good seed corn cannot be judged wholly by the appearance of the ear and of the plant that pro- duces it. If the seed of two ears much alike in size, shape and general appearance are planted, the seed of one ear may produce double the yield of the other. One n.ay produce few or no barren stalks and the other many. TTie purpose of seed corn selection is to secure a high yield and to have good ears produce good ears. The object of an ear-to-row test of seed corn is to find out the difference in yield, percentage of barren stalks, character of stand, etc., produced by ears that are almost similar. DIRECTIONS: Materials. Balances or small scales, tape measure, ten small paper bags, ten stakes, each about 1 8 X 1 X 3 inches. Plot. The plot may be any section of a field which is to be planted to corn, and should have the same preparation and care as the rest of the field. It should be marked both ways with planter or marker. If the part of the field selected for the plot is in a corner or along one side it is important to have at least four rows of ordinary field corn on the outside. This is to provide turning rows to protect the plants of the plot from injury. Selection and record. Ten of the best ears of the season's seed corn should be selected. Number the ears from one to ten on small pieces of card board which are tacked on the butts of the ears. Make a record of each ear, using appropriate number, according to following blank form: No. of Eai Weight in Ounces Ciicumference No. of 1 Inch From Butt Middle 1 Inch From Tip Rows 1 2 3 4 5 6 7 8 9 10 Preparation for planting. Number paper bags from one to ten. Shell 350 kernels from the middle part of one side of each ear, placing the corn, as soon as shelled, in bag corresponding to number of the ear. Tie the ten ears together and put away in safe place for use the next year. Drive stakes at end of rows that are to be planted, and number stakes from one to ten. Planting. For each row use the kernels from the bag corresponding to the number on stake (row 1 from bag 1, etc.). Use a hoe and plant at uniform depth. Plant one hundred hills with exactly three grains to a hill. Each hill should be at the point marked by intersection of lines of marker. Ker- nels may be covered as they are dropped, or later by means of a harrow. Observalions during the grorving season. A record should be kept of the plants of each row in regard to characters indicated in the previous exercise. All barren stalks should be detasseled or removed before the tassels open. Harvesting. Each row should be harvested and weighed separately. The proportion of good ears to nubbins and inferior ears should also be determined for each row, either by weighing or numbering. The product of the rows having the highest yield and largest proportion of good corn should be saved for seed corn. Summary of the result. The productive value of each original seed ear is thus tested. For example, if rows 1 and 7 produce 70 pounds or more, and all the rest 60 pounds or less, the test shows that ears 1 and 7 are superior to all the other ears for seed corn. Second year. Use the original seed ears whose numbers correspond to the two or four of the rows making the highest yield of the previous year. Plant alternate rows of 100 hills each from these ears. When tassels appear, detassel every other row. This will insure crossing. At harvest time, save for seed the corn from the detasseled rows. Select the best ears for seed the following year. These seed ears will be a fairly pure strain of high yielding corn, and should be planted the third year in a field or part of a field to itself. APPLICATION. By making a test of this kind it is possible to separate and develop a high yielding strain of corn. The first year's test is made to determine which ears give the greatest yield or have the greatest pro- ductive capacity. The second year plot is to produce seed from ears selected by the first year test. The product of the detasseled ears of the second year plot when planted the third year should furnish enough seed corn for an entire farm. REFERENCES: I. pp. 62-69: II. p. 23: IV, pp. 225-228; V, pp. 165-169; VI, p. 112; VII, pp. 25-29; VIII. pp. 164-165; IX, pp. 123-129. Essentials of Successful Field Experimentation, Ohio State Agricultural Experiment Station, Circular 100. For Belter Crops, International Harvester Co. (Chicago), Pamphlet. HoTV to Crow an Acre of Corn, U. S. Department of Agriculture, Farmers' Bulletin 537. EXERCISE 34 SCORING AND JUDGING WHEAT EXPLANATION: Milling qualities, or flour production, determine the value of wheat for seed or for the market. This is based upon the quality of wheat as to purity, weight, soundness, freedom from dirt, size and color of berries, and other conditions affecting milling. Viability, or germinating power, should be considered also if wheat is to be used for seed. In estimating the quality of wheat a record is made of the various characters, and from this record the sample may be judged by scoring. DIRECTIONS: Several samples representing a variety of qualities should be provided. Each sample should be carefully examined and reported upon as follows: Weight per bushel. Measure and weigh a fraction of a bushel and estimate the weight per bushel. A box may be used instead of a measure and the fraction of bushel determined by comparing the cubic capacity of the box with the number of cubic inches in a bushel. (One bushel contains 2150 cubic inches). Color. May vary with kind of wheat, but should be uniform for same variety. Good wheat should not be bleached or discolored, as by weathering. Unsound grain. Reduces milling value and indicates poor harvesting. Wheat is graded on market largely with reference to unsound grain. No. I wheat should have no sprouted, decayed or injured grains from any cause; No. 2, no sprouted and very few injured grains; No. 3, if dry and otherwise in good condition, may contain some sprouted and injured grains. Foreign mailer. Refers to weed seed and dirt. Hardness and texlure. Cut a grain in two. If no starch shows it is hard or vitreous; if much starch, it is soft and starchy. Size. Uniformity is desirable. Grains should be plump and not shrivelled. Viability. Use 100 grains. Place in pan or dish on moist paper, cover with moist paper or cloth and keep moist. When germination takes place subtract grains not germinated from 100. The difference is the percentage of viability. Form of Report Na Date No. of Sample Weight per bushel — lbs Weight of 100 grains — grams Color. Whitish — per cent Yellowish — per cent Clear amber — per cent Dull amber — per cent Clear red — per cent Dull red — per cent. Unsound grain — per cent Foreign matter — per cent Hardness and texture Hard and vitreous — per cent.. Medium — per cent Soft and starchy — per cent Size of grain. Large — per cent Medium — per cent _. Small — per cent Viability — per cent ■! I- Using report of examination t)f samples for reference score the samples as follows: Weight: Should be 60 pounds per bushel. Cut two points for each pound below this. Soundness and dirt. Cut two points for each per cent of dirt, weed seed, sprouted and unsound or injured grain. Uniformity in hardness and texture. Divide the sample into three parts (or refer to percentages in report: (I) hard and vitreous grains; (2) soft and starchy; (3) medium or intermediate. The sample belongs to class having the largest percentage of (1), (2) or (3). Cut one point for each per cent of extreme, and one point for each two per cent of intermediate. If the largest class is intermediate the other two classes are regarded as extremes. If sample is fairly uniform separate into two classes and cut one point for each two per cent of difference. Illustration: If in 100 grains 80 are hard and vitreous, 15 soft and starchy, and 5 intermediate, cut 15 points from soft and starchy grains and 2 1-2 points for intermediate. Uniformil]) in color. Cut two points for each per cent of off color. Yellow grains in hard winter wheat would be considered off color. Commercial grade. This is indicated by Nos. i, 2, or 3 and determined by amount of unsound grain as already explained. Score Card For Wheat Name Date No. of Sample Points 1 Milling quality (Flour making Weight 50) 25 1 1 1 1 1 Soundness 25 1 1 1 1 Uniformity 50 Hardness and Texture 1 1 1 1 1 1 1 1 1 1 30 1 1 Color _ 20 1 1 1 1 1 Total 1 00 1 ! 1 1 1 REFERENCES: I. pp. 62-69; II, p. 150; III. p. 83; V, pp. 185-186; VIII, pp. 83-84; XIV, pp. 172-173. EXERCISE 35 SCORING AND JUDGING IRISH POTATOES EXPLANATION: The market value of the potato depends upon its freedom from injury and disease, condition as to cracks, bruices, and absence of green color. Potato scoring is based upon these points. There is no generally accepted standard for judging potatoes, but the following suggestions include the essential points to be considered. DIRECTIONS: Several samples of five tubers each should be provided. Examine each sample with reference to the following points, and indicate value of each character in points on score card. , Soundness and freedom from dirt. Each sample should be sound and free from dirt. In exhibits, unsound or dirty tubers disqualify the exhibit. Trueness to t^pe. Indicated by uniformity in size, shape, color and other characteristics of the class or variety. Should not s/ion; mixture. Cut two points for each tuber showing characters of another variety. Uniformity of exhibit. Shape, length and circumference are considered. Cut two points for each off tuber. Shape of tuber. Should be round, oval or long, conforming to class or variety. In length a tuber should not be over two and one- fourth times its own circumference at widest part, and should not be flattened to exceed one- fourth its diameter. Cut one point for each one-eighth inch excess of length or flatness. Color. Should conform to class or variety and be free from green (indicating sunburn). For example, a reddish tuber in a sample of white potatoes would be objectionable. Cut one point for each off tuber. Flesh. When split, the tuber should show no hollows. It should also be firm, clear in color, with no dark rings or other discolorations. Should not be woody or fibrous. Cut one point for each off tuber. Skin. Should be smooth without cracks or other blemishes. Cut one point for each square inch of blemish. £j)es. Should be shallow, small and few in number. Cut one point for each off tuber. Size. Medium — not too large or too small. Average weight for early varieties is eight ounces; for late varieties, twelve ounces. Cut one pwint for tuber weighing one ounce more or one ounce less than these weights. Score Card for Potatoes Na Points Number of Sample Trueness to type | 10 Uniformity | 10 Shape of tuber | 20 Color I 10 Flesh I 20 Skin I 10 Eyes I 10 Size I 10 I Total I 100 REFERENCES: IX. pp. 110-118. Polato Investigalions, Ohio State Agricultural Experiment Station, Bulletin 174. Good Seed Potatoes and How to Produce Them, U. S. Department of Agriculture, Farmers' Bulletin 533. EXERCISE 36 TEST PLOT FOR SEED POTATOES EXPLANATION: Seed potatoes, like ears of seed corn, vary in their productive capacity. A single seed tuber may have a combination of all desirable points, but there is no way of telling from its appearance whether or not it will produce many other tubers of the same kind. It may have been the only tuber of value in the hill which produced it, and may when planted yield but a single tuber per hill. After a selection is made of tubers for seed, some of the best ones should be tested to find out what kind of yield they will give. DIRECTIONS: Plot. Reserve a row near the middle of that part of the field or garden where the regular crop of potatoes is to be produced. Preparation for Planting. If twenty-five tubers are to be tested procure that many small paper bags and number from I to 25. Cut each tuber into four nearly equal parts and place in a bag. Planting. Beginning with one end of the row plant the pieces of the first tuber in four hills — one piece to a hill. Tlie planting distance should be the same as that of the regular planting. Plant the pieces of the second tuber in the same way, making the first hill two feet from the fourth hill of the first unit. Continue in the same way until the twenty-five tubers are planted, being careful to separate each hill- unit from the next by a space of two feet. These spaces make it easier to distinguish the four-hill units. Care and cultivation. The test row should receive the same protection by spraying for fungi and insects and the same cultivation as is given the rest of the patch. The object is to test the value of the seed potatoes under average conditions. Croiving season record. A record should be kept of each hill-unit, and notes made of vigor of plants, differences in growth, etc. Harvest. The potatoes dug from each group of four hills should be put into separate piles. When they are dry the potatoes should be examined and a record made of the number and weight of good potato tubers, weight of small or inferior ones, and total weight. Several four-hill groups from various parts of the regular planting should also be weighed and yield comparedl with the best yields from test row. The tubers from the hill-units in the test row having the largest number of good tubers should be put into bags and saved for seed to be used the following year. The following form for record sheet is suggested for summary: Date of Planting Dales of Cultivation Dates of Spraying Growing Record Weight of Good Tubers Total Weight I.., ? 3 . 4 5 Etc APPLICATION: A test row for seed potatoes is a means of selection based upon production, by which a high yield strain is developed. If the potatoes selected from high yielding hills are not sufficient to furnish seed for the entire planting of the second year, they should be planted in separate rows to produce seed for the third year. REFERENCES: I. pp. 58-59; II, p. 23; IV, pp. 225-228; VI. p. 112; VII, p. 30; XIV, p. 443. Good Seed Potatoes and How to Produce Them, U. S. Department of Agriculture, Farmers' Bulletin 533. Potato Investigations, Ohio State Agricultural Experiment Station, Bulletin 1 74. Methods of Breeding and Improving the Potato Crop, Cornell University, Stale Agricultural College, Reading Course for Farmers, Number 43. EXERCISE 37 BABCOCK MILK-TEST FOR BUTTER FAT EXPLANATION: Tlie quality of milk is largely determined by the amount of butter fat it contains. The Babcock milk test is a simple means of finding the percentage of butter fat in milk. DIRECTIONS: Material and apparatus. Samples of milk, Babcock milk-tester, and test bottles, sulfuric acid, pipette, acid measure, watch, hot water. Mixing. Just before testing, thoroughly stir sample by pouring from one bottle or jar into another, repeating several times. Measuring. By means of pipette measure out exactly 1 7.6 cubic centimeters of milk. This is done by placing the small end of the pipette into the milk, the other end in the mouth, and sucking the air out of the pipette until the milk rises above 1 7.6 cc. mark. Quickly place the finger over the end of the pipette which has been in the mouth. Slightly change the pressure of the finger at the end of the pipette, allowing the milk to flow out slowly until the 1 7.6 cc. mark is reached. Then press firmly on the end of the pipette so as to keep the milk from running out. Adding milk to test hollle. Place the small end of the pipette against the inside of the neck of the lest bottle and incline both the pipette and bottle. Gradually remove the finger from end of pipette and allow the milk to flow slowly into the bottle. Adding acid to milk. Fill the small acid measure with sulfuric acid to the point marked 17.5 cc. Pour acid into test bottle by holding the acid measure and test bottle at an angle so that the acid will run down the side of the bottle. Mixing acid and milk- When the acid has been poured into the test bottle the acid and milk will be in separate layers. It is necessary to have the milk and acid thoroughly mixed. Do this by tilting the bottle slightly and rotating until the liquid becomes uniformly dark brown and quite hot. Separation of fat — ]st Step. Place test bottle with milk and acid thoroughly mixed, in its place in the machine together with other bottles which have been similarly prepared from other samples of milk. Turn the crank of the machine for five minutes at the speed indicated in directions for use of the machine (usually 75 turns per minute). Separation of fat — 2nd Step. Add sufficient hot water to each bottle to bring the contents up to the neck of the bottle. Replace in the machine and whirl, at same speed, for two minutes. Separation of fat — 3rd Step. Add more hot water to each bottle, bringing the contents nearly to the top of the marks on its neck. Replace and whirl for another minute. Finding percentage of fat. The fat should form a clear column in the neck of the bottle. Since the reading should be made while the fat is hot, the bottles should be set in a pan of hot water (130-140 degrees). On the neck of the test bottle is a graduated scale with spaces from to 10, each space being divided into 5 equal parts. Each space corresponds to 1 per cent of fat, and each division of space to .2 of I per cent. Read the scale at the two extremes of the fat column. The difference will be the percentage of butter fat in the sample. Thus if the lower reading is .4 and the upper reading 4.2, the difference will be 3.8, which means 3.8 per cent butter fat, or 3.8 pounds of butter fat per hundred pounds of milk. APPLICATION: The Babcock test may seem at first somewhat difficult and complicated, but after a little practice It may be made with ease and accuracy. The class in agriculture should arrange to test samples of milk sent in by the patrons of the school. REFERENCES: II, pp. 333-337; III. pp. 326-329; IV, pp. 307-309; V, pp. 342-343; VI, p. 174; VII, p. 345; VIII. p. 320; IX, pp. 185-188; X, pp. 173-174. The Golden Stream, International Harvester Co. (Chicago), Pamphlet. EXERCISE 38 MILK RECORD EXPLANATION: The amount of butter fat as determined by the Babcock test indicates the quality of the milk. The value of a dairy cow depends upon the quantity produced as well as upon the quality. An animal pro- ducing milk of low quality (small percentage of butter fat) may produce a large quantity, so that the total yield of butter fat may equal that of another animal whose milk is higher in quality but deficient in quantity. Whether the milk is sold whole, or separated and the cream sold on the butter- fat basis, it is important to know the daily production of individual cows. Such a record is not only important in estimating the value of a cow as a milk producer, but also may be used as a basis for calculating rations. DIRECTIONS: Preparation. Send to State Agricultural College or State Experiment Station for a milk record sheet, or prepare one by ruling a large sheet of strong paper as follows: Mon^ Year FARM MILK RECORD Owner's Mame>.. cow's NUMB R i 3 4 5 6 7 6 c ' .0 H r^ 13 ,4 .-> i B DATE. AM PM AM PM AM PM AM PM AM PM A>^ PM A.M P.M AM P.M AM P.M AM PM AM P.M AM PM A.M PM AM ^iA. AM PM AM PM 1 ■ i i A 5 6 7 6 9 10 1 T li 13 14 15 • 16 17 18 19 iO . a li iT, 34 ab a7 i6 li 30 31 1 ToTol TesT LtftBunerFot 1 Volue _ — "• Tack the record sheet near place of milking. Suspend a pair of milk scales near the record sheet. Recording. At each milking period weigh and record the amount of milk from each cow under her name or number on the record sheet. Keep record of each cow for one month. Test the milk of each cow for butter fat at the beginning and end of the month. Results. Find the total amount of milk produced by each cow during the month. If whole milk is sold estimate value in pounds or gallons (one gallon of milk weighs 8.66 pounds). Using market price for whole milk as a basis, calculate value of each cow's production for a month. If cream or butter is sold find the total amount of butter fat in the milk produced by each cow. For example, if a cow produces 900 pounds of milk testing 4.2 per cent of butter fat in a month, the total amount of butter fat in pounds is calculated by finding 4.2 per cent of 900 (900 X..042=37.8). Estimate value as based upon market price for cream and butter. One pound of butter fat will make one and one-sixth pounds of butter. APPLICATION: By means of carefully kept milk records the productive value of individual cows may be determined, and also a most profitabie way of selling milk. If cream or butter is sold allowance should be made for skim milk based upon its feeding value, or upon market price. REFERENCES: II, p. 333; VII. p. 337; IX, pp. 189-191. The Golden Stream, International Harvester Co. (Chicago), Pamphlet. EXERCISE 39 CARE OF MILK ON THE FARM EXPLANATION: Milk is sometimes called a "perfect food" because it contains protein, carbohydrates, and fats in nearly the right proportion for human needs. It is also an almost perfect food for various kinds of very small plants known as bacteria. Bacteria find in milk a favorable medium for very rapid growth and often render it unwholesome. The problem of handling milk so that it will be wholesome and fit food for man is largely one of control of bacteria. This control is effected in two ways: ( 1 ) great cleanliness in all stages of handling to decrease the number of bacteria entering milk; (2) cooling milk rapidly and keeping it cool to prevent any large increase of bacteria. Bacteria are abundant everywhere, especially about barns. They are always present in dirt and dust. Milking, therefore, should be done with strict attention to cleanliness: clean milking place free from dust; clean cows; clean milkers, clean, dry hands; clean, sanitary milk pails. A few simple experiments will show the value of these suggestions in the control of bacteria in milk. DIRECTIONS: Prepare the following form in which to insert figures later: 2. 3. 5. 7. Conditions in handling or producing milk. Containers: a. Rinsed in cold water b. Carefully cleaned using boiling water.. Place of milking a. In barn (ordinary conditions) b. In open, free from dirt or dust Condition of cow a. Without cleaning b. Carefully cleaned Milker Without special care Clean hands and coat a. b. Pail a. b. Ordinary pail Sanitary pail Cooling milk a. Not cooled b. Rapidly cooled and kept cool Combination of methods a. Ordinary methods b. Sanitary method observing I, 2, 3, 4, 5, 6, 7 No. of Hours until Milk Sours Difference in Hours between a and b The object of this exercise is to compare the results of ordinary methods of milking and handling milk with sanitary methods. The test consists in comparing keeping qualities as indicated by the number of hours between milking and the time the milk begins to sour. In each experiment the same quantities of milk (one-half pint will be enough) and the same kind of container (milk bottle, mason jar, or tm cup) should be used, and the same conditions as to temperature should be observed. At end of the experiment insert the number of hours in its proper place in the form. Compare the keeping qualities of milk in (a) and (b) in the following: 1. Conlainer: a. Using a container that has been merely rinsed in cold water. b. Using a container that has been rinsed in cold water and then carefully scalded with boiling water. (Boiling water destroys most bacteria.) 2. Place of milking: a. In barn in presence of dust. b. In the open or in some place free from dust. 3. Condition of coTv: a. From cow not cleaned before milking. b. From cow that has been cleaned by brushing parts of body likely to drop dirt into the milk, and by thoroughly wiping the udder with damp cloth. 4. Milker: a. With no special pains as to cleanliness. b. With clean coat or jacket, and hands perfectly clean and dry. 5. Pail: a. Use ordinary wide mouth pail. b. Use sanitary or small mouth pail. 6. Cooling milk: a. Not cooled, and no special effort to keep it cool. b. Rapidly cooled as soon as milked, and then kept in as cool a place as possible. 7. Combination of methods: a. Procure and handle milk in ordinary way (a). b. Procure and handle milk according to methods indicated in (b) of 1,2, 3, 4, 5, 6, 7. APPLICATION: Unless the "ordinary methods" referred to are better than those usually practiced in milking and handling milk on the average farm considerable difference in keeping qualities will be shown between (a) and (b) of each of the above experiments, but especially noticeable in (7). REFERENCES: I, pp. 225-227: II. pp. 325-33! ; III. pp. 299-303; IV, pp. 301-304; V. p. 340; VI. pp. 172- 173; VII, pp. 334-335; VIII, pp. 320-321 ; X, pp. 168-170, 327-328. Production of Sanitary Milk, U. S. Department of Agriculture, Bureau of Animal Industry, Circular 1 42. Score-card Sps/eni of Dairy Inspection, Ibid., Circular 199. The Care of Milk and Its Use In the Home, U. S. Department of Agriculture, Farmers Bul- letin 413. Bacteria In Milk, Ibid., Farmers' Bulletin 490. EXERCISE 40 BALANCED RATIONS: NUTRITIVE RATIO EXPLANATION: A farm animal needs food ( 1 ) to maintain its body by replacing wastes that the cells are con- stantly forming and by furnishing energy in the form of heat to keep up body warmth and of mechan- ical energy or power for its movements; (2) to provide materials for growth, fat, milk, wool, eggs, or energy for labor. A ration is a combination of food materials that will meet the needs of an animal. If merely sufficient to maintain its body (I), it is called a maintenance ration; but if used to put the animal in condition for market, to enable it to produce milk, wool or eggs, or to give power for work (2), the food needed is called a productive ration. Any ration must contain protein, carbohydrates, and fat. It is important that these three kinds of food be combined in the right proportion or be properly balanced to suit the needs of the animal. This proportion is usually expressed by the ratio of the amount of digestible protein to the amount of digesti- ble carbohydrates and fat. This relation is called nutritive ratio. The nutritive ratio of a ration may be easily calculated by referring to tables showing percentages of digestible nutrients. DIRECTIONS: Carbohydrate equivalent of fat. It is estimated that a quantity of fat produces 2.25 times as much heat as the same quantity of carbohydrates. It is customary to reduce the fats to a carbohydrate basis by multiplying the percentage of fat by 2.25. Thus 4 per cent fat is equal to 9 per cent of carbohy- drates (4 X 2.25 = 9). Nutritive ratio. Using oats for illustration, we find the digestible nutrients as follows: Protein, 9.2 per cent; carbohydrates, 47.3 per cent; fats 4.2 per cent. The carbohydrate equivalent of 4.2 per cent fat is 9.45 (4.2 X 2.25 = 9.45). The total carbohydrate value is 47.3+9.45 = 56.75. The nutritive ratio, therefore, is 56.75 -^ 9.2 = 6. 1 -J-. This relation would be usually expressed by stating the nutritive ratio as 1 to 6. 1 . In other words, in oats, the proportion of digestible protein to digestible carbohydrates (including carbohydrate equivalent of fat) is as 1 to 6.1, or 1 pound of protein to every 6.1 pounds of digestible carbohydrates. Method of determining nutritive ratio. As indicated in the illustration above there are four steps in the process of calculation: (I) Reduce fat to its carbohydrate equivalent; (2) add carbohydrate equivalent to carbohydrates; (3) divide sum by protein; (4) express in form of ratio by using 1 for first term and quotient of (3) for second term (I to 6.8; I to 7.1, etc.). Table of Digestible Nutrients (Compiled from Henry's "Feeds and Feeding") Kind of Feed Prolein Per Cent Corn (dent) 7.8 Corn and cob meal _ _ _ 4.4 Corn Stover, field cured* 1.4 Corn fodder, green 1 .0 Corn silage* 1 .4 Al fa! fa, green 3.6 Al fal fa hay* 1 0.5 Timothy hay* ;. 2.8 Red Clover hay _ 7.1 Cow Pea hay 9.2 Oats 9.2 Gluten meal _ 25.8 Wheat bran* 12.2 Linseed meal, old process _ 29.3 Linseed meal, new process 28.2 Cotton Seed meal* 37.2 Tankage 50.1 Carbohydrates Per Cent Fats Per Cent 66.8 4.3 60.0 2.9 31.2 0.7 11.9 0.4 14.2 0.7 12.1 0.4 40.5 0.9 42.4 1.3 37.8 1.8 39.3 1.3 47.3 4.2 43.3 n.o 39.2 2.7 32.7 7.0 40.1 2.8 16.9 12.2 0.0 11.6 PROBLEMS: 1. Determine nutritive ratio for the feeds in above fable marked with (*). 2. Protein is less abundant than other nutrients, hence more expensive. The value of feed, there- fore, depends largely upon the amount of protein it contains. Based upon percentages of digestible pro- tein compare value of alfalfa hay with timothy hay; wheal bran with cotton-seed meal; corn with oats. 3. Suppose alfalfa and timothy hay cost the same per ton, which is the most economical to use, where one can be used as well as the other? Why? 4. How many pounds of each digestible nutrient: protein, carbohydrates, and fats in 100 pounds of corn meal? In 500 pounds of corn silage? In one ton of clover hay? In 10 pounds of wheat bran? 5. How many pounds of digestible protein, carbohydrates, and fats in the ration of 10 pounds of timothy hay, 12 pounds of corn, 2 pounds of cotton-seed meal? What is the nutritive ratio of this ration ? REFERENCES: I. pp. 216-218; II, pp. 316, 318; III, pp. 281-282; V, p. 386; VI, pp. 217-219; VII, pp. 292-293; VIII, pp. 294-295; IX. pp. 197-203; X, pp. 188-190; XII, pp. 272-273. Feeding Daif^ Cows, Ohio State Agricultural Experiment Station, Circular 128. The Golden Stream, International Harvester Co. (Chicago), Pamphlet. EXERCISE 41 COMPUTING RATIONS. DAIRY COW EXPLANATION: Standard rations for all farm animals have been determined by experiment. These feeding stand- ards, although too general to apply to each individual case, are a safe guide to follow in compounding rations. Three steps are necessary in computing a ration: DIRECTIONS: Steps. I . Determine (by ytfeight) digestible protein, carbohydrates and fats in the quantity of each ingredient of the ration being used, or planned to be used. This is called trial ration. 2. Find total amount of digestible protein, carbohydrates and fats in trial ration. 3. Correct the trial ration by comparing with standard ration, making such additions or changes as are necessary to conform closely to the standard ration. Illustration of method as applied to dairy cotv. Suppose the ration used is 50 pounds of corn silage, and 10 pounds of alfalfa hay. Make the following form in which to insert figures later: DIGESTIBLE NUTRIENTS 50 lbs. com silage . 10 lbs. alfalfa hay. Protein lbs. Carbohydrates lbs. Fats lbs. 1. On consulting table of digestible nutrients in previous exercise it will be found that silage con- tains 1.4 per cent protein, 14.2 per cent carbohydrates and .7 per cent fat. Find these percentages of 50, and insert in the line after corn silage in form above. Then find the percentages of each nutrient as indicated in table for alfalfa, calculate the amount of each in 10 pounds of alfalfa, and insert in the line after alfalfa. The following result is obtained: Digestible Nutrients Protein Carbohydrates Fats Lbs. Lbs. Lbs. 50 lbs. corn silage 7 7.1 .35 10 lbs. alfalfa hay 1.05 4.05 .09 Total nutrients 1.75 11.15 .44 The nutritive ratio for this ration is 1 to 6.9. [1 1 .1 5+ (.44x2.25) = 1 2.1 4; 12.14-^1.75 = 6.9] 2. The standard ration (according to Professor Haecker, University of Minn.) for maintenance of a dairy cow weighing 1000 pounds is .7 pound of protein, 7 pounds of carbohydrates, and .1 pound of fat. To this must be added nutrients for milk production as follows: Daily Allowance of Digestible Nutrients Crude Protein Carbohydrate Fat Lbs. Lbs. Lbs. For each pound of 3.0 per cent milk 0.040 0.19 0.015 For each pound of 3.5 per cent milk - 0.042 0.21 0.016 For each pound of 4.0 per cent milk _ 0.047 0.23 0.018 For each pound of 4.5 per cent milk 0.049 0.26 0.020 For each pound of 5.0 per cent milk 0.051 0.27 0.021 For each pound of 5:5 per cent millc 0.054 0.29 0.022 For each pound of 6.0 per cent milk 0.057 0.31 0.024 For each pound of 6.5 per cent milk 0.061 0.33 0.025 For each pound of 7.0 per cent milk „ 0.063 0.35 0.027 If the ration is intended for a I 100 pound cow producing 30 pounds (daily) of 4 F>er cent milk the standard will be the following: Digestible Nutrients Protein Carbohydrates Fats Lbs. Lbs. Lbs. For maintenance .77 7.7 .11 For producing 30 lbs. 4 f)er cent milk 1.41 6.9 .54 Total daily requirements 2.18 14.6 .65 Nutritive ratio I to 7.4 — (This ratio is wider than given by some other authorities.) 3. Comparing the trial ration with the standard, it will be found lacking in each of the three nutri- ents, and having too narrow a nutritive ratio. Digestible Nutrients Protein Carbohydrates Fats Lbs. Lbs. Lbs. Trial ration 1.75 11.15 .44 Standard 2. 1 8 1 4.6 .65 Difference 43 3.45 .2 1 This must be corrected by adding nutrients which will bring it close to the standard. Since the difference is greatest in carbohydrates, the feed used to balance the ration should have a relatively large amount of carbohydrates in proportion to protein and fats. On consulting the table (Ex. 40) it will be found that corn has such a proportion. Five pounds of corn will furnish .39 pounds of protein, 3.34 pounds of carbohydrates, and .215 pound of fat which very nearly make up the differences of the two rations. The ration corrected by use of 5 pwunds of corn compared with standard is as follows: Digestible Nutrients Protein Carbohydrates Fats Lbs. Lbs. Lbs. Corrected ration _ _ 2. 1 4 1 4.49 .655 Standard ration 2. 1 8 1 4.6 .65 Difference _ 04 .11 .005 The differences are so small that the trial ration may be considered properly corrected. PROBLEMS: 1. Correct the following ration for 1000 pound dairy cow producing 25 pounds of 4.5 per cent milk daily: 10 pounds of clover hay, 20 pounds of corn stover, 6 pounds of corn. 2. The standard ration for 1000 pound horse at heavy work contains these digestible nutrients: Protein, 2.5 pounds; carbohydrates, 15 pounds; fats, .8 pound; nutritive ratio I to 6. Correct the following ration for a horse weighing 1250 pounds and hard at work: Corn, 16 pounds; timothy hay, 1 4 pounds. 3. The standard ration, per 1 000 pounds live weight, for hogs weighing about 1 00 pounds, con- tains these digestible nutrients: Protein, 4.5 pounds; carbohydrates, 25 pounds; fat, .7 pound. (To adjust this standard for a 100 pound animal divide each nutrient by 10). Correct ration consisting of 4 pounds of corn. 4. The standard ration for fattening cattle, first period, per 1000 pounds live weight, contains these digestible nutrients: Protein, 2.5 pounds; carbohydrates, 15 pounds; fat, .5 pound. Correct the following ration for 1200 pound steer: Ear corn, 27 pounds; stover, 5 pounds. 5. Estimate cost at current market price of ingredients in each of the above corrected rations. REFERENCES: I, pp. 216-218; II, pp. 318-319; V, pp. 383-386; VI, pp. 219-220; VII, pp. 293-296; VIII, pp. 295-297; IX, pp. 203-208; X. pp. 188-190; XII. pp. 274-287. I. Muzzle 8. Neck 15. R.bs 22. Thighs 2. J.w 9. Withers 16. Barrel 23. Hind legs ?! Face 10. Shoulders 17. Loin 24. Udder A. Forehead 11. Fore Legs 18. Hips 25. Teals 5. Eyes 12. Crops 19. Rump 26. Milk veins 6. Ears 13. Chest 20. Pin bones 27. Milk wells 7. Throat 14. Back 21. Tail EXERCISE 42 SCORING AND JUDGING DAIRY CATTLE EXPLANATION: Use of score card in slock judging. A score card consists of a description of parts of an ideally per- fect animal, with these parts arranged in a systematic order so as to show their relative importance. This method of examination gives training in seeing the parts of an animal rather than the animal as a whole. In using the card examine each part in order. If a part of the animal examined seems perfectly developed, enter in the column headed "Student's Score" the full value in points as indicated in the column headed "Standard." If the part is not good, "cut" or take off as many points from the standard as will show how far from perfect it is or how many points it must be improved to make it perfect. No cut should be made of less than one-fourth of one point, or greater than one-half of the total number of points of the standard. Begin with the first part mentioned in the standard on the score card and continue until all parts have been taken in the order given. When completed the column headed "Student's Score" will con- tain the value in points for each part of the animal. The sum of these points represents the score of the animal. If the animal were perfect the score would be 100, but animals are seldom perfect enough to warrant a score of more than 80. Method of study. Referring to diagram at head of each exercise learn the location of parts of the animal. Examine parts with hand. Do not depend entirely upon the eye. Study use of parts, and their value in estimating the worth of an animal as a whole. This will depend upon the purpose of the animal. For example the parts of a dairy animal are considered from the standpoint of milk production; of a beef animal from the standpoint of beef production. Be able to give reasons for score assigned to each part. Compare score with that made by others on the same animal, and discuss reasons for differences in rating values of various parts. Confer when possible with competent stock judges as to value of parts of different types of animals. Observe stock judging at fairs or at stock shows. Stock judging is a matter of practice and experience, hence every opportunity should be taken to develop intelligent judgment of an animal's worth. DIRECTIONS: 1. Identify all parts shown in diagram of a dairy cow by careful study of animal itself. 2. Study parts indicated in score card in their order, first going over them, in order to understand them, but without marking scores. The main facts to be considered are stated after various items in the score card. Dairy Cattle THE SCORE CARD Cow Stan- dard Points deficient Scale of Points Student'i Score Cor- rected Stiidml'" Score Cor. reeled Student'. Score Cor- reiled Head — 8 Points I . Muzz/e, broad, nol thin 1 1 1 1 2 2 2. Jaiv, strong, firmly joined 3. Face, mediunn length, clean, free from extra flesh 4. Forehead, broad between eyes, slightly dished... 5. Ryes, large, full, mild, bright 6. Ears, medium size, fine texture, secretions oily and abundant, yellow color FOREQUARTERS— 10 Points. 7. Throat, clean I ' 8. Neck, 'o"8' spare, smoothly jointed to shoulders, free from dewlap 2 3 3 1 1 6 3 3 10 2 1 4 1 1 3 2 15 5 4 6 2 3 4 9. Wiihers, narrow, sharp 10. Shoulders, slopmg, smooth; brisket light 11. Fore /egs, straight, clean, well set under body. not too close together Body — 25 points. 12. Crops, free from fleshiness 13. Chest, deep, roomy; floor broad 14. Bacl(. straight, strong; spinal processes wide apart 15. Ribs, long, deep sprung, wide apart 16. Barrel, deep, long, capacious 17. Loin, broad, strong Hindquarters — 12 points. 18. Hips, prominent, wide apart, not fleshy 19. Rump, long, level, not sloping 20. Pin Bones, wide apart 21. Tail, neatly set on. long, tapering 22. Thighs, spare, nol fleshy, wide apart 23. Hind legs, well apart, giving ample room for Mammary Development — 20 points 24. Udder, large, very flexible, attached high behind, carrying wel! forward; quarters even, nol cut up 25. Teats, wide apart, uniformly placed, con- 26. Mill( Veins, large, tortuous, extending well forward 27. Mi7^ iKc/Zs. large General Appearance — 15 points. 28. Disposition, quiet, gentle 29. Health, thrifty, vigorous 30. Quality, free from coarseness throughout; skin 31, Temperament, nervous indicated by refinement in | head, neck and forequarters 6 1 Total 100 1 1 REFERENCES: I, pp. 195-197; II, p. 269; III, p. 333; IV. p. 262; V, p. 331; VI. p. 159; VII. p. 343; VIII. p. 317; X, p. 159; XII, pp. 183-195. Live Slocl( Judging for Beginners, Purdue University, Agricultural Experiment Station (La Fay- ette. Ind.). Circular 29. The Score Card in Siocl( Judging, U. S. Department of Agriculture, Bureau of Animal Industry, Bulletin 61. 1. Muzzle 8. Shoulders 16. Chest 24. Purse 2. Eyes 9. Brisket 17. Fore flank 25. Rump 3. Face 10. Jaw 18. Crops 26. Tail head 4. Forehead II. Breast 19. Ribs 28. Thigh 5. Ears 12. Dewlap 20. Back 30. Hocks 6. Neck 13. Arm 21. Loin 31. Shanks 7. Shoulders vein 14. Shin 22. Hips 15. Legs 23. Hind flank EXERCISE 43 SCORING AND JUDGING BEEF CATTLE EXPLANATION: Read general directions on use of score card and method of study (Exercise 42). DIRECTIONS: 1. Identify all parts shown in diagram of beef animal by careful study of the animal itself. 2. Study parts indicated on score card in their order, first going over them, in order to understand them, but without marking scores. The main facts to be considered are stated after the various items on the score card. THE SCORE CARD Beef Cattle Fat Steei Stan- dard Points deficient SCALE OF POINTS StudcDt'a Score Col- lected StudcDi'i Scoie Cor- rected Student', Score Cor- rected General Appearance — 40 points. 1 IVeighl, estimated lbs. Actual lbs. ac- cording lo age. Example 12mos.. 850 lbs; ^0 nifn 1 son lbs 10 10 8 12 2 1 4 2 2 4 8 8 8 2 1 3 4 4 2 2. Form, straight top and underline; deep, broad, low set, slylish, smooth, compact, symmelricall 3. Qua/i/p, fine, soft hair; loose, pliable skin of me- dium thickness; dense, clean, medium-sized 4. Condition, deep, even covering of firm mellow flesh; free from patches, ties, lumps, and rolls; Head and Neck — 7 points. 5. Muzzle, broad ; moulh large ; nostrils large and 6. E\)es, large, clear placid '. 10. Neck. short. thick, blenJira smoothly with FOREQUARTERS — 9 points. 12. ShouUers, smoothly covered, compact, snug, neat Body — 30 points. 15. Chest, full, deep, wide; girlh large; crops full 16. Ribs, long, arched, thickly and smoothly fleshed 17. Bacl(, broad, straight, thickly and smoothly fleshed Hindquarters — 14 points. 21. Rump, long, wide, level; tail-head smooth; pin- 22 Thlehs deeo full 24. Legs, wide apart, straight, short; shanks fine. 100 1 1 1 1 1 1 II 1 li i REFERENCES: I. pp. 192-194: II. p. 270; III, p. 227; IV. p. 265; V. p. 325; VI. p. 164; VII. p. 344; VIII, p. 314; X. pp. 162-163; XII. pp. 174-182. Live Stock Judging for Beginners, Purdue University, Agricultural Experiment Station (La Fay- ette. Ind.). Circular 29. American Breeds of Beef Cattle, U. S. Department of Agriculture. Bureau of Animal Industry. Bulletin 34, 1. Mouth 11. Windpipe 2. Nostril 12. Crest 3. Chin 13. Withers 4. Nose 14. Shoulder 5. Face 15. Breast 6. Forehead 16. Arm 7. Eye 17. Elbow 8. Ear 18. Forearm 9. Lower law 19. Knee 10. Throat-latch 20. Cannon 2 1 . Fetlock joint 22. Pastern 23. Foot 24. Fore flank 25. Heart girth 26. Coupling 27. Back 28. Loin 29. Rear flank 30. Belly 31. Hip 32. Croup 33. Tail 34. Bullocks 35. Quarters 36. Thigh 37. Stifle 38. Gaskin or lower thigh 39. Hock EXERCISE 44 SCORING AND JUDGING DRAFT HORSES EXPLANATION: Read general directions on use of score card and method of study (Exercise 42). DIRECTIONS: 1. Identify all parts shown in diagram of draft horse by careiul study of animal itself. 2. Study parts indicated on score card in their order, first going over them, in order to understand them, but without marking scores. The main facts to be considered are stated after the various items on the score card. Draft Horses SCORE CARD Market Sta.. dard Points deficient SCALE OF POINTS Student's Score Cor- tected StudcDt's Score Cor- reeled Sludenl'i Score Cor- rected General Appearance — 19 points. 6 4 6 1 1 2. fVeighl. over 1600 lbs., estimated lbs.:actual 3. Form, broad, massive, well proportioned, blocky 4. Qua/i/y, refined; bone clean, hard, large, strong; tendons clean, defined; skin and hair fine; 5. TemperamenI, energetic; disposition good Head and Neck — 9 points. 6. Head, lean, proportionate size; profile straight 3 1 Stan, dard Points deficient SCALE OF POINTS Student's Score Cor- rected Student's Sccie Col- lected Student's Sccre Cor- rected 1 1 2 1 1 2 1 1 II. Muzzle, neal; nostrils large, open, free from dis- 1 ^ 12. Necl(. well muscled, arched; ihroatlatch clean; 1 1 i FOREQUARTERS 24 poinls. 13. Shoulders, moderately sloping, smoolh. snug, ex- 3 14. Arm, short, strongly muscled, thrown back, well set 1 2 2 2 1 2 8 3 2 2 2 2 1 2 2 1 3 2 6 2 1 16. Knees, deep, straight, wide, strongly supported 17. Cannons, short, wide, clean; tendons defined, set back 1 19. Pasterns, moderate length, sloping, strong, clean. .- 20. Feet, large, even size, sound; horn dense, waxy; sole concave; bars strong; frog large, elastic; heal wide and one-fourth to one-half the lineal length of toe 21. Legs, viewed in front, a perpendicular line from the point of the shoulder should fall upon the center of the knee, cannon, pastern and foot. From the side, a perpendicular line dropping from the center of the elbow joint should fall upon the center of the knee and pastern joints 1 1 1 Body — 9 points. 23. Ribs, long, well sprung, close; coupling strong.... HtNDQUARTERS 30 points. 28. Croup, not .markedly drooping, wide, heavily 30. Quarters, deep, broad, heavily muscled, thighs 1 1 33. Cannons, short, wide, clean; tendons defined 1 2 36. Feet, large, even size, sound; horn dense, waxy; sole concave; bars strong: frog large, elastic; heel wide, and one- fourth to one-half the 6 3 6 3 37. Legs viewed from behind, a perpendicular line from the point of the buttock should fall upon the center of the hock, cannon, pastern and foot. From side, a perpendicular line from the hip joint should fall upon the center of the fool and divide the gaskin in the middle, and a perpendicular line from the point of the buttock shoujd run parallel with the Action — 9 points. 39. Trot, free, springy, balanced, straight 1 Total 100 1 1 REFERENCES: I, pp. 183-191 ; II. p. 253: III. p. 214; IV. p. 252; V, pp. 343-346; VI, pp. 181-183; VII. pp. 319-321: VIII. pp. 310-31 1;X. p. 194: XII. pp. 138-172. Live Stock Judging for Beginners, Purdue University, Agricultural Experiment Station (La Fay- ette, Ind.), Circular 29. es £+ I. Snout 8. Fore leg 15. Tail 22. Stifle 2. Eye 9. Hind leg 16. Fore flank 23. Hock 3. Face 10. Breast 17. Hind flank 24. Pasterns 4. Ear n. Chest line 18. Hip 25. Dewclaw 3. Jowl 12. Back 19. Rump 26. Foot 6. Neck 13. Loin 20. Belly 7. Shoulder 14. Side 21. Ham EXERCISE 45 SCORING AND JUDGING FAT HOGS EXPLANATION: Read general directions on use of score card and method of study (Exercise 42). DIRECTIONS: 1. Identify all part shown in diagram of fat hog by careful study of the animal itself. 2. Study parts indicated on score card in their order, first going over them, in order to understand them, but without marking scores. The main facts to be considered are stated after the various items on the score card. SCORE CARD Lard Hogs Fat Stan- dard Points deficient SCALE OF POINTS Sludenl'i Score Cor- rected Studenl'. Score Cor- rected Student's Score Cor- rected General Appearance — 30 points. 1. IVeight score according to age 4 10 6 10 1 1 1 1 2 2 8 2 2 4 8 9 9 3 3 3 9 1 7 2. Form, deep, broad, medium length; smooth com- pact, symmetrical; standing squarely on med- 3. Quality, hair smooth and fine; bone medium size, clean, strong; general appearance smooth 4. Covering, finished; deep, even, mellow, free from Head and Neck — 8 points. 6. Eyes, not sunken, clear, not obscured by wrinkles.. 10 Neck thick short, smooth to shoulder FOREQUARTERS — 12 points. 11. Shoulders, broad, deep, smooth, compact on top... 13. Legs, straight, short, strong; bone clean, hard; pasterns short, strong, upright; feet medium Body — 33 points. 16. Bacl(, broad, strongly arched, thickly and evenly covered 1 7. Loin, wide, thick, strong rri ::;::::::;; - Hindquarters — 17 points. 19. Hips, wide apart, smooth 20. Rump, long, level, wide, evenly Reshed 21. Ham, heavily fleshed, full, firm, deep, wide 22. Legs, straight, short, strong; bone clean, hard; pasterns short, strong upright; feel medium C ;. i T«iai ino REFERENCES: I, pp. 200-203; III. p. 259; IV, pp. 280-281 ; V. pp. 359-360; VI. p. 195; VIII. pp. 322-323; X, p. 213; XII. pp. 207-229. Live Stock Judging for Beginners, Purdue University, Agricultural Experiment Station (La Fay- ette, Ind.), Circular 29. I. Muzzle 9. Ear 17. Back 25. Leg or mutton or thigh 2. Moulh 10. Neck 18. Loin 26. Crops 3. Nostril II. Shoulder vein 19. Hip 27. Dock or tail 4. Lips 12. Top of shoulder 20. Ribs or side 28. Twist 5. Nose 13. Shoulder 21. Fore flank 29. Hind leg 6. Face 14. Chest 22. Belly 7. Forehead 15. Brisket 23. Flank 8. Eye 16. Fore leg 24. Rump EXERCISE 46 SCORING AND JUDGING SHEEP EXPLANATION: Read general directions on use of score card and method of study (Exercise 42). DIRECTIONS: 1. Identify all parts shown in diagram of mutton sheep by careful study of the animal itself. 2. Study parts indicated on score card in their order, first going over them, in order to understand them, but without marking scores. The main facts to be considered are stated after various items on the score card. SCORE CARD Mutton Sheep Fat Stan- dard Points deficient SCALE OF POINTS Student's Score Cor- reeled Stud'-ni's Score Cor- rected StudcDl's Score Cor- rected 1. Age .. .... 8 10 10 10 2 5 1 1 4 4 6 6 2 4 4 5 1 4 4 4 General Appearance — 38 points. 3. Form, long, level, deep, broad, low set, stylish .. 4. Qualii\f, clean bone; silky hair; fine pink skin; light in offal, yielding high percentage of meal 5. CoTiiiition, deep, even covering of firm flesh, es- pecially in regions of valuable cuts. Points mdicating ripeness are, thick dock, back thickly covered with flesh, thick neck, full purse, full flank, plump breast Head and Neck — 7 poinis. 6. Muzzle, fine, mouth large; lips thin; noslrib large 7. E^es, large, clear, placid 10. Ears, fine, alert FOREQUARTERS — 7 points. 12. Shoulders, covered with flesh, compact on top; 14. Legs, straight, short, wide apart, strong; forearm full ; shank smooth, fine Body — 20 points. 15. Chest, wide, deep full 17. Hacl(, broad, straight, long, thickly fleshed Hindquarters — 16 points. 19. Hips, far apart, level, smooth 20. f^ump, long, level, wide to tail-head 21. Thighs, full, deep, wide . . 23. Legs, straight, short, strong; shank fine, smooth... Wool — 12 points. 24. Qua/i'/p, long, dense, even 25. Quality, fine, pure; crimp close, regular, even... 26, Condition, bright, sound, clean, soft light Tola! 100 1 REFERENCES: I. pp. 197-220; II, p. 277; III. p. 243; IV. p. 271 ; V. pp. 352-353; VI. pp. 191-193; VII. p. 351 ; VIII, pp. 326-328; X. p. 206; XII. pp. 196-208. Live Stocl( Judging for Beginners, Purdue University, Agricultural Experimpnt Station (La Fay- ette. Ind.). Circular 29. 'i!r!ioi;flcri;iii,i:i:iy.'!!,i';'n'i''';!irii'pii;.ia'!);iii;:'iii[iiwiiiii!Wi>imir,iiiiitrgi!' LIBRARY OF CONGRESS 0Q0E7flES37D