i cme pete,
Pew Pork
State College of Agriculture
At Cornell University
Bthaca, N. VB.
Library
Cornell University Library
21.F71
(Forestry; miscellaneous papers]
Te
wh
92
The Profession of Forestry
The Profession of Forestry
INCLUDING
An Address
BY
MR. GIFFORD PINCHOT
Chief of the Bureau of Forestry, U. S. Dept. of Agriculture.
AND AN ARTICLE ON
Study in Europe for American Forest Students
«
BY
OVERTON W. PRICE,
Supt. of Working Plans, Bureau of Forestry.
Also a List of Reference Books on Forestry
PUBLISHED BY
THE AMERICAN FORESTRY ASSOCIATION,
WASHINGTON, D. C.
190}.
446193
PREFACE,
‘¢ As yet forestry in America is young. In its progress toward maturity
it must develop new methods to meet the unfamiliar conditions with which it
has to deal. Rules and practices which were devised without reference to
American forests cannot always be counted on to fit American needs. Perhaps
nothing has done more to retard the progress of forestry in America than the
disregard of its intimate and friendly relation to lumbering—a relation which
was almost wholly overlooked for years after the advocates of forest protection
first brought their cause to public attention. In the eyes of many of its early
friends the lumberman was a vandal whose inordinate greed called for constant
denunciation, while to the Jumberman the ideas of the forest reformer had no
relation whatever to the affairs of practical life. Since that early day lumber-
men and foresters have been drawing together, and much progress has been
made toward the right opinion, which may be expressed by saying that
lumberman and forester are as needful to each other as the axe and its helve.
Without the axe the helve has little weight; without the helve the axe is lack-
ing both in reach and in direction."—Gifford Pinchot: The Adirondack
Spruce. Preface.
THE PROFESSION
OF FORESTRY,
An address delivered before the students of Vale University.
(Reprinted from the Yale Alumni Weekly by permission.
Revised. )
BY GIFFORD PINCHOT, FORESTER OF THE U. S. DEPARTMENT OF AGRICULTURE.
HE subject matter of the profession
of Forestry is equally distinct from
street tree-planting on the one side
and landscape architecture on the other.
It has to do with wooded regions, with the
productiveness of forests, chiefly through
conservative lumbering, and, in the treeless
parts of the United States, with planting
for economic reasons. Except for a com-
paratively small area of desert land in the
West, the whole land surtace of the
United States is included in the possible
field of work for the forester. How ex-
tensive this field is will appear from the
fact that the woodland in farms alone, in
1890, comprised more than 200,000,000
acres, or more than four times the area of
the National forest reserves.
THE OPENING.
The first question asked by a man who
has in mind forestry as his profession
usually concerns the chance of finding
work when his preparatory study is ended.
The sources of demand for trained for-
esters at the moment are comparatively
few, but they are increasing with remark-
able rapidity. The great lumbering con-
cerns, such as the International Paper
Company, which controls more than 1,-
000,000 acres of Spruce land, are rapidly
getting to see that it is worth their while
to employ trained foresters. One Yale
man has been employed by the company
just mentioned; another college graduate,
not a Yale man, has charge for a com-
pany of certain phases of its lumbering in
Maine; and five lumber companies have
already applied to the Bureau of Forestry
for working plans for the management of
their tracts. The demand from this
source may be expected to increase very
greatly within the next ten years, as the
great holders of timber land come to
realize more generally that conservative
lumbering pays better than the destructive
methods now employed.
In a similar way mining companies will
eventually find it to their interest to em-
ploy foresters. The owners of game
parks have already taken steps in this
direction. Private owners of large areas
such as Biltmore Forest in North Caro-
lina, the property of George W. Vander-
bilt, Ne-Ha-Sa-Ne Park in the Adiron-
dacks, owned by W. Seward Webb, a
Yale man, and the contiguous land held
by the Hon. Wm. C. Whitney, another
Yale man, are already under the manage-
ment of trained men. The need of for-
esters to care for the forest interests of the
several States is already making itself felt.
States such as New York, with its mil-
lion and a quarter acres of forest reserves ;
Pennsylvania, with its newly-created De-
partment of Forestry and its growing State
forest reserves; Michigan, with its Forest
Commission and its State reserves which
are being rapidly formed; North Caro-
lina, with its Geological Survey thor-
oughly interested in forest study; New
Jersey and Maryland, of which the same
is true; Maine, New Hampshire and
several others, with their Forest Com-
missions; Minnesota, with its Fire War-
den law, its State Park and the beginning of
a system of State forest reserves, and other
States are rapidly creating a demand for
foresters, and would be doing so still more
rapidly if men were available to do the
work. Finally, the National Government
already employs a considerable number of
men, and is rapidly extending the work
which requires them. The General Land
6 THE PROFESSION
Office, to which is intrusted the police
and patrol of the National forest reserves,
has this year an appropriation of $300,000
for the care and protection of about forty-
seven million acres of forest reserves. At
present there are no trained foresters
among its officials, but in view of the vital
importance of forest preservation, espe-
cially in the West, and of the great and
growing public interest in its extension,
this system of appointment cannot be ex-
pected to last.
The Bureau of Forestry, which is
charged with the general progress of
forestry and the interests of private for-
est lands, in the subdivision of the Gov-
ernment’s forest work, is at this moment
unable to find enough suitably trained
men to supply its needs. It would be
easily possible, it is true, to secure Ger-
mans or other foreigners, but a consider-
able experience has convinced me that,
except in rare cases, such as that of the
present forester to the Biltmore Estate,
the attempt to use foreign-born men
trained abroad is not likely to succeed.
COMPENSATION.
The second question asked by the
prospective forester very often relates to
the rate of pay. I cannot answer this
question any more accurately than by
saying that trained foresters now receive
about the same rate of pay as instructors
and professors at Yale. Those in the
employ of the Bureau of Forestry receive
from $720 to $2,500 a year. Scientific
work under the Government is always
underpaid, and it is most probable that
those foresters who enter the service of
lumber companies or other commercial or-
ganizations will fare better. It is even
possible that a few men may develop such
skill that they will be called in consulta-
tion over specially difficult problems.
Such work will naturally pay well.
As with teaching, so with forestry; by
no means all the compensation comes in
the form of dollars. While the life of the
forester in the field is often rough, many
times exceedingly hard, and always with-
out most of the comforts of life, it is to
those of us who have been following it
OF FORESTRY.
the most delightful of occupations. Briefly
stated, it deals, on the scientific side,
with the life-history of forests and forest
trees, with their behavior in health and
disease, their reaction under treatment,
and their adaptation to and effect upon
their surroundings. On the economic
side, it has chiefly to do with reconciling
the perpetuation of the forest with the
production of timber. Measurements of
the stand of timber per acre, and of the rate
of growth of single trees and whole for-
ests by counting rings, and subsequent
calculations, often form a consideraable
part of a forester’s work. There is often
a great deal of office work. It is by no
means the easy existence it has often been
supposed to be by the many men who
have taken up forestry, and then have
dropped it. But it has a charm which
lies perhaps first of all in the fact that in
the United States it is almost an untried
field.
ORIGINAL WORK DEMANDED.
Unless forestry as a profession has
qualities to recommend it other than those
I have already mentioned, it would
scarcely be worthy of consideration be-
fore many other lines of work. It has,
however, two peculiarities in which it
stands somewhat by itself. In the first
place, because the field is practically
untouched, a forester finds himself com-
pelled to do original work at every turn.
The pleasure of investigation of this kind
is very real, and to those of us who are
practicing forestry it is one of its two great
attractions. The second lies in the fact
that because forestry is almost unknown
in the United States, in no profession is it
easier for a man to make his life count.
I need not dwell further on the vastness
of the interests it touches nor the great
utility of forestry to the nation, but I
should like to emphasize this statement—
in few other professions can a man lead
so useful a life.
WHAT THE PROFESSION DEMANDS.
These are the things which forestry
offers. Now as to what it demands. In
the first place success in forestry, as in any
other profession, must come largely from
THE PROFESSION OF FORESTRY. 7
the possession of what we know so well
as *¢ Yale spirit,” the habit of accomplish-
ment and the willingness to do the work
first and count the cost afterward. It is
interesting to note here that a majority
of the young Americans who have fitted
themselves for technical forest work are
Yale men. Whatever the connection or
the special fitness may be which brings
Yale men into this line of effort and
achievement, I should like to see the re-
cruits from Yale come in fast enough to
maintain something like the old propor-
tion.
After the ‘* Yale spirit” comes sound-
ness of body and hardiness, for foresters
must often expect the roughest kind of
life in the woods. The helpmeet of
hardiness is a contented spirit. There
is no more pernicious character than a
grumbler in camp, and nothing will help
so much to get field work done as the will-
ingness to bear privation cheerfully.
A man who takes up forestry will often
find the field work exceedingly or even
unexpectedly hard, for it combines severe
mental work with severe bodily labor,
under conditions which make each one
peculiarly trying. Work in the woods
differs profoundly from camp life as it is
usually understood. Foresters get a cer-
tain amount of hunting and fishing, and
every forester will do his work better for
a wholesome love of the rod and gun, but
the line between work and play is still
sharply drawn.
I have been speaking of the funda-
mental qualities which are more or less
necessary to success in any vigorous out-
door life. There are several additional
capacities with which the forester should
be well endowed. The first of these is
the power of observation. It is often dif-
ficult to say a préor¢ whether a man has it
or not. In many cases it makes itself
known as a love of hunting or fishing, or
a general pleasure in all outdoors. To the
forester it is one of the most essential
qualities in his mental equipment. Fi-
nally, perseverance, initiative, and self-re-
liance are peculiarly necessary, because
the forester is so often withdrawn from
the inspection of his superiors and alto-
gether dependent on his own steadfastness
and devotion to keep him up to the high
standard he should set himself for his
work. In a new field of effort this is
especially likely to be true. It is one of
the distinguishing characteristics of the
profession of forestry.
PREPARATION.
The preparation for forestry as a pro-
fession should, as a rule, begin with a col-
lege or university course, and, as a rule,
should be continued after graduation for
not less than two years.
The first.step in the preparation for for-
estry as a profession is for the possible for-
ester to discover whether his conception of
forestry is a right one. Todo so he must
get into the field. The Bureau of Fores-
try made some provision to meet this re-
quirement when it established the grade of
Student Assistant, with pay at the rate of
$300 a year. Men who take this position
are required to assist in the work of the
Bureau with the same steadiness and de-
votion to duty as in all its other members,
and they are employed so far as possible
in work of peculiar value to them and at
the same time of use in the general pro-,
gress. All their expenses are defrayed
while in the field. In addition to the spe-
cific advantage this grade offers in enab-
ling a man to take part in actual forest
work under a trained forester, and so to
discover what the profession really means,
it has a special usefulness in enabling men
who cannot at first afford fuller prepara-
tion to support themselves for a time while
getting the first step in their forest educa-
tion. It does not replace a forest school,
nor is it the intention that it should. No
future forester who can possibly afford to
take a course, either at Cornell, under Dr.
Fernow, at Biltmore, under Dr. Schenck,
or at Yale, under Professor Graves should
fail todo so. I repeat with all emphasis
that work as a student assistant cannot
take the place of study at a forest school.
The number of positions as Student
Assistant is decidedly limited, and gradu-
ates or students of forest schools will al-
ways be preferred for appointment. No
one will be received as Student Assistant
8 STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS.
A
who has not definitely made up his mind
to take up forestry as a profession, although
of course no pledge to that effect is re-
quired.
In my judgment the best course for the
future forester to pursue, so far as his sys-
tematic training is concerned, is first, a
full course at a university during which
he should acquire some knowledge of
the auxiliary subjects necessary in for-
estry; second, at a forest school, prefer-
ably where practical work in the woods
goes hand in hand with theoretical instruc-
tion; and third, a year abroad. The latter
is of the greatest value, because in this
country forestry is too young to show the
effect of silvicultural treatment on the
various kinds of forests; yet it must be re-
membered that much of. what is learned
abroad must be unlearned later. This
experience in a region where forestry is of
old date is, in my judgment, a most essen-
tial portion of a forester’s education. It
goes without saying that vacations, as far
as possible, should be spent in the woods.
Forestry on its executive side is closer
to lumbering than any other calling, and
a good knowledge of the lumberman’s
methods is an essential part'of a forester’s
education. But it must not .be forgotten
that it offers a field for pure research of
the widest and most attractive character
for those who are inclined and can afford
to occupy it. It is so broad a subject that
as yet we do not quite know what its de-
velopment and its subdivisions are going
to be.
GirFrorpD PincuHotT.
STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS.
By Overton W. Price.
Superintendent of Working Plans, Bureau of Forestry.
HE training necessary for an Amer-
ican forester has not yet been fixed
by hard and fast lines. The neces-
sity, however, for a man to map out his
course and to supply his deficiencies largely
on his own responsibility has disappeared
with the establishment of American forest
schools. They have already done much
to set a high standard for technical train-
ing and thereby to hasten greatly the
sound development of forestry in this
country. With the creation of opportu-
nities for systematic study at home, it is
natural for the forest student to jump to
the comfortable conclusion that study
abroad is no longer essential. He soon
becomes aware also of the familiar fact
that European forest methods can rarely
be applied without modification here, and
this may seem to him to remove all prac-
tical advantage from studying them on the
ground. He sees, too, that there are now
fewer trained men in this country to sup-
ply the need for foresters than there are
likely to be in the future, and he naturally
wants to get his start with as little loss of
time as possible.
It 1s true that there-are few European
forest methods which we can use entirely
without modification. It is also true that
European methods have been rich in sug-
gestion in the application of practical for-
estry to American forests. The American
forest student who puts aside a chance to
see forestry in Europe makes the same
sort of mistake that a medical student
would be guilty of, who ignored an oppor-
tunity to walk the best hospitals. The
work which falls toa forester here requires
of him a more comprehensive grasp of his
profession than is needed where forestry
is already established upon a firm footing.
In Europe, forest management, in order
to be successful, has only to follow those
methods which have been proved advis-
able. In this country, the forester must
depend for the most part upon his own
ability to make the most of forest problems.
And since he has but few patterns to fol-
low at home, it would seem that the more
STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS. 9
he knows of the practice and development
of forestry abroad, the better equipped
will he be for his work.
Three questions are likely to present
themselves to the forest student who has
decided to supplement in Europe the course
of study which he has followed here:
where to go, how long to stay, and the
probable cost of the undertaking.
Those who have been well grounded at
a forest school and have seen something of
American forests and American lumber-
ing, can gain much from a year abroad.
Those who wish to follow to the end a
particular line of investigation may use
two or three years to advantage, but for
the usual purpose of the forest student, one
year will suffice. The right man, equipped
with a good knowledge of German and a
carefully considered plan of campaign, can
gain something from a six months’ stay.
It requires, however, a thorough prepara-
tory knowledge of European forest condi-
tions, to lend practical benefit to a shorter
trip. The disadvantage for the forest
student of flying trips to Europe can
scarcely be put too strongly.
The forest student, with one year
abroad at his disposal, will probably find
it advisable to spend the first one or two
months, according to his requirements, on
one range under an English-speaking forest
officer. This will enable him to brush
up his German without loss of time, and
steady work in the same place for a month
or more will give him the insight into
European forestry which he needs, much
better than would the same period spent
in a cursory inspection of several ranges.
English-speaking forest officers are rare
in Europe. The Uehlingen range in the
Southern Black Forest, under the charge
of Oberfdrster Jager, has been the start-
ing point for several American students,
and it would be difficult to find one more
favorably situated or a forest officer with
a happier faculty for making matters clear
to the beginner. While at Uehlingen the
student will have a chance to acquaint
himself thoroughly with the Baden work-
ing plan method, which, of the several in
force in the German States, is the simplest,
the broadest, and the least unsuited to
American forest conditions. Uehlingen
is within easy reach of several instructive
ranges, among which are Waldshut, St.
Blasien, and Wolfsboden. The Waldshut
range in the foothills of the Schwarzwald,
where the vineyards of the Rhine valley
give way first to coppice woods and then
to high forests of Beech and Oak, forms a
strong contrast in type and management
to Wolfsboden and St. Blasien, both moun-
tain ranges stocked chiefly with Silver Fir
and Spruce.
His term at Uehlingen ended, the student
will do well to see something of Swiss for-
ests before he turns northward. The Sihl-
wald, town forest of Zurich, deservedly
famous for its Beech forests and the excel-
lence of its management, is full of interest
and of practical hints. There are records
of its systematic management since 1417.
It is the only range in Europe in which all
its own forest produce is worked up. It
has a sawmill, lathes for turning tool
handles, a plant for impregnating paving
blocks and telegraph poles, and machines
for the shaping and bundling of fuel. No
raw material is sold. The Sihlwald con-
tains also a most ingenious and labor-saving
system of timber slides, firewood slides,
and forest railways.
The town forest of Winterthur does not
contain many features from the study of
which Americans can gain direct practical
benefit. It is instructive, however, in
showing what exceedingly favorable local
conditions can do in shaping the manage-
ment of a forest. The well-stocked Win-
terthur forests, which begin within a stone’s
throw of the town, have produceda revenue |
of $10 per acre per annum for the last thirty
years. They are managed with almost the
same care that we give to a garden, be-
cause through their nearness to an excel-
lent market the value of firewood and tim-
ber exceeds enormously the cost of raising
them.
Whether the student sees something of
forest management in the Swiss Alps, or
in those of Bavaria or the Tyrol, will de-
pend upon the best economy of his time.
It is preferable that he should see it in
Switzerland, where the preservation of the
forests of the higher mountains is of vital
10 STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS.
importance. It was in Switzerland, that
reckless lumbering of the mountain forests
resulted in such serious damage from land-
slides and avalanches to farms in the Alpine
valleys, that an urgent and successful pub-
lic appeal was made to the Government to
take their management into its own hands.
On his way northward from Switzer-
land, the student will do well to see some
ranges of the middle and northern Schwarz-
wald. Of the former, Staufen is the best
known. It is the largest range in Baden,
and the management of its mountain for-
ests is particularly instructive. Of the
latter, the ranges of Baden-Baden, Wol-
fach, and Herrenwies are representative.
Wolfoch. an excellent example of the se-
lection system, is full of suggestion for
«American foresters.
It is but a short distance into Bavaria
from the northern Black Forest. Bavaria
is rich in forests and presents a very wide
range of local conditions. The Spessart is
well known and teaches forcible lessons
in silviculture and national economy. It
has been thought best to describe this forest
district at some length since no American
student abroad will fail to see it, while its
form of management may be of some in-
terest to those who confine their studies to
is country.
The Spessart which is situated in the
northwestern portion of Bavaria covers an
area of about 115,000 acres. There are
few forests of the same size, the whole-
sale lumbering of which would realize so
enormous a profit. The stand is chiefly
Beech and Oak, many of the latter 400
years old. with a diameter of three feet or
more and a clear length of sixty feet—
certainly the finest Oak in Europe and
sometimes equalled, but seldom excelled,
by the White Oak of our Southern and
Middle States. One can walk for hours
in this district among Oaks worth from
fifty to two hundred dollars a tree and the
total value of this timber in the Spessart
is estimated at nearly one million dollars.
Bavaria is not a wealthy kingdom.
Wars and enforced preparation for war, a
generally unfruitful soil, the extravagances
of the royal house, and, especially in the
south, and idle and pleasure-loving pea-
santry, have all led to poverty. Under the
careful husbandry of the present ruler,
Luitpold, Prince Regent, much has been
done to improve matters and especially to
remove the heavy load of debt laid upon
the people by the vagaries of the unhappy
King Ludwig II. However, Bavaria is
not yet in such a position that the presence
of an additional million of dollars in the
treasury would be a matter of little im-
portance. In view of this, her conser-
vative management of the wealth of the
Spessart is all the more praiseworthy.
The villages in the valleys of the Spes-
sart and upon the outskirts of the forest
owe their existence to the wood-working
industries, which are the natural conse-
quence of the presence of so large a body
of marketable timber. There are several
saw mills where the Oak and Beech are
cut up, but the chief industry is the manu-
facture of oaken staves for wine casks,
which find ready sale in the vallevs of the
Main and the Rhine. Of the peasantry of
the Spessart and its environments, very
few are not connected in one way or an-
other with the manufacture of lumber or
staves or in getting out the raw material,
while the great majority are directly de-
pendent upon these sources of labor for
their daily bread. If the Bavarian gov-
ernment, therefore, were to,authorize the
cutting of all marketable timber in this
district, without regard to the maintenance
of a sustained annual yield, a large num-
ber of people would soon be thrown out
of employment and great suffering would
inevitably result. To realize fully how
severe this suffering would be, would en-
tail upon the reader some study of the
Bavarian peasant and the economic and
social conditions under which he lives.
His tools, his mode of life and his educa-
tion differ but little from those of his an-
cestors, and his language is scarcely intel-
ligible to his own countrymen of a better
class. Tosuch a man, the power to grap-
ple with new conditions, to seek a fresh
home and other means of employment, is
denied. And even were this not the case,
Germany, where the supply of labor ex-
ceeds the demand, in practically all the
trades and especially in the case of com-
STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS. Il
mon labor, offers a poor field to those in
search of work.
To lumber on the principle of a sus-
tained annual yield, in other words to
take out of a forest in one year the quantity
of wood which has actually been produced
in that year, is the basis of forest manage-
ment in Germany, because it has there
been found to yield better returns upon the
capital invested in the forest than any other
form of management. If the sanctioned
annual yield, and no more, be harvested
each year, the forest will, under proper
care, continue to produce the sanctioned
annual yield for ever, just as a good invest-
ment continues to produce its annual in-
terest. If the sanctioned annual yield be
utilized with close regard to the silvicul-
tural requirements of the forest, it will in-
crease in proportion with the improvement
in the condition of the forest as a whole.
There are cases, however, among which
is the Spessart, where the utilization of the
sanctioned annual yield alone, may not
prove immediately the best financial policy.
This is sometimes the result of local eco-
nomic conditions, but more often of the
condition of the forest itself. The Spes-
sart, from the standpoint of the forester,
is not in good order. Its old Oaks and
Beeches are still of high value, but many
of them long ago passed their maturity.
To leave them standing, is to incur loss
from two sources: from the decay of the
timber they contain; and because the space
they occupy in the forest might be filled
by sound healthy young trees, producing
wood of good quality at a comparatively
rapid rate. The best silvicultural meas-
ure would be, to remove, as soon as pos-
sible, all these Oaks and Beeches which
have passed their maturity, without regard
to the limit prescribed by the sanctioned
annual yield. Then, after the forest has
been put in good condition, by these ‘+ im-
provement cuttings,” further utilization
might be based upon its actual production,
without danger of this production being in
a measure offset by the presence, in the
forest, of trees, which are not only growing
exceedingly slowly, but many of which are
losing rapidly in value through decay.
However, in the Spessart, in order to con-
tinue to provide the peasants of the neigh-
borhood with material for their sawmills
and for the manufacture of staves, it is
necessary to cut upon exceedingly con-
servative lines. The Oak of this region is
divided into three well-defined classes, in
point of age: Class I comprises Oak of
about 400 years old. Class II, Oak 250
years old, and Class III, Oak 100 years
old. In order, therefore, to maintain a
sustained annual yield, Classes I and II,
both of which are merchantable timber,
must be removed slowly enough to allow
Class III to be ready for the market by
the time the removal of Classes I and II
is effected.
Since the Oak is the more desirable tree
in the Spessart, producing timber of high
value while the Beech asa species suit-
able only for firewood is subordinate in
importance, the first object of the manage-
ment is the raising of merchantable Oak
timber of as good a quality and in as short
a time as possible. The Oak being a
tree exceedingly intolerant of shade, has
not the power of forming the dense ma-
ture stands characteristic of trees strongly
tolerant of shade, as for example the Adi-
rondack Spruce. In the case of pure woods
of Spruce, the struggle for existence is
prolonged indefinitely and the stand re-
mains dense to a great age, because each
tree which helps to form it, possesses the in-
herent power to endure excessive and long
continued shade with but little detriment
beyond decrease in its rate of growth. With
the Spessart Oak, the case is different.
The tree needs so much light, that it soon
succumbs to suppression. The struggle
for existence is consequently short, the
stand thins out rapidly through the death
of over-topped trees and becomes sparse
and open at an early age. This may not
seem to be a matter of much importance. It
is, however, a source of so much difficulty,
that it has rendered the raising of Oak
timber in pure woods impossible in Ger-
many. Not only does it prevent, by the
formation of an insufficient, scanty stand,
the full utilization of the space it occupies,
but also results in the reproduction of
short, branchy trunks and knotty defective
timber. One of the most incontrovertible
12 STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS.
of silvicultural laws establishes the im-
possibility of raising timber of good qual-
ity in a wood which has been open from
anearly age. For the production of long,
cylindrical trunks free from branches,
trees must have light from above, but as
little side light as possible.
Realizing that it would be impossible
to grow Oak timber in pure Oak woods,
the Bavarian foresters had to find some
other means of growing it. They turned
to nature, and they found that Oak does
not occur pure in the Spessart, but scat-
tered in small groups and single trees
among the Beech. They saw that the
Oaks growing in this way were tall and
straight, clean boled and cylindrical, and
finer upon the whole than any Oak they
had seen elsewhere. They noticed also
that the Oaks were everywhere older than
the Beech, with their crowns well above
the leaf cover of the latter and forming
what is called a ‘‘two-storied forest,” the
Oak above and the Beech below. :
It was evident that ‘¢the Oak must have
its head in the light and its feet in the
shade,” and that growing singly and in
groups in dense stands of Beech, with its
crown well above the general canopy, en-
joying the full influence of the sunshine
with its trunk shaded by the Beech around
it, conditions were suited to its develop-
ment. In other words it was clear that
the Beech served as a nurse for the Oak,
forcing it to grow towards the light and
admitting that light only from above, with
tall cylindrical trees, excellently adapted
to use as timber, as the result. Incident-
ally also, Beech was seen to serve still an-
other purpose, in shading the ground and
covering it with its heavy leaf litter, thereby
adding greatly to the moisture and fertility
of the forest floor. To systematize a
method of manageinent easy of applica-
tion, embodying the good features of na-
ture’s method without involving the same
prodigal use of time, was the problem.
If'no attempt had been made to perpetuate
the two-storied forest of Beech and Oak,
it might certainly have continued to occur
naturally, asin the past. To trust entirely
to chance, however, in the perpetuation of
a valuable timber tree, would not have
been good forestry in the case of a species
handicapped by infrequent seed years,
strong demands upon light and a rate of
growth so much slower than that of the
Beech as to render it constantly liable to
be choked out by the latter. In order to
counteract these difficulties, the following
plan was adopted:
Spots seldom more than a fraction of an
acre in extent, suited especially to the Oak,
were selected in mature Beech forest.
These were cut clean of the Beech which
covered them and sown broadcast with
acorns. After four or five years when the
young Oaks had obtained a start sufficient
to enable them to hold their own against
the faster growing Beech, the Beech wood
surrounding the Oak groups was repro-
duced by natural means; that is, successive
cuttings were made in it, by which the
light necessary to the germination and
growth of Beech seedlings was admitted
to the soil, and after these had become
established in sufficient quantity, the old
Beech wood was gradually removed, allow-
ing a young wood of Beech to take its
place. At the same time, many young
Beech sprung up in the Oak groups as
well as around them, and the final result
was exactly what had been desired—a two-
storied forest with the Oak above and the
Beech below. This system has _ been
adopted permanently and every year fresh
blanks are cut in the Beech woods and
sown with acorns, thereby insuring to
Spessart peasants of future generations an
ample supply of the same fine Oak timber
that the present generation is enjoying.
It may occur to the reader that although
the conservative system of management
adopted by the Bavarian government for
the forests of the Spessart may contain
some instructive features in view of the
interests at stake, the silvicultural treat-
ment of the Oak contains no hints of prac-
tical value for the management of Amer-
ican forests. It is true that so intricate a
method involving large expense and much
technical skill for its application, is justi-
fied in the Spessart only because the value
of land and timber render it profitable. It
is also true that such conditions do not yet
exist generally in America. But because
STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS. 13
a system cannot be adopted as it stands,
it does not follow that. some modification
of it may not be employed where oppor-
tunity arises. The Spessart does not illus-
trate merely how Oak may be grown suc-
cessfully in mixture with Beech. It teaches
broad principles of sylviculture and proves
the value of close observation. It was the
study of these forests that induced Sir
Dietrich Brandis, late Inspector General
of Forests in India, to adopt in 1850-a
similar system in Burma for the raising
of Teak in mixture with Bamboo, the
Teak forming the overwood and the Bam-
boo the underwood; a system which has
served as a source of large annual revenue
tothe British crown. In our own northern
woods we find the Hemlock and Pine as-
sociated in the same way as are the Spes-
sart Beech and Oak, and in various parts
of the United States other species form
analogous cases, where nature points the
way towards the best means of growing
the local timber tree.
The student who has completed a visit
to the Spessart will be within easy reach
of the Steigerwald and the town forest of |
Bamberg, the one well known for its
mixed forests of Scotch Pine and Beech
and the other for the management of pure
Scotch Pine woods under an elaborate
system of clean cutting and sowing. He
should also see something of the ancient
town forest of Nuremberg, which consists
chiefly of woods of Scotch Pine on a soil
that is little more than pure sand. The
forest has an interesting history and is an
instructive example of what skill and pér-
severance can do in rearing woods in 0
poor a locality, where frequent insect
ravages and long standing rights to‘'the
collection of litter go to make matters
harder for the forester.
The Bayerischer Wald covers a moun-
tain range in southwestern Bavaria, run-
ning parallel with the Béhmer- Wald, a
second range, the summit of which forms
the dividing line between Bavaria and Bo-
hemia. Here exist forest conditions mark-
edly in contrast to those prevailing gener-
ally in Germany. In this isolated and
sparsely settled region where lack of facil-
ities for the transport of timber and dis-
tance from the market greatly lower
stumpage values, the form of forest man-
agement is peculiarly instructive for
Americans. Gi va
In Saxony, where the forests are chiefly
pure Spruce and where natural reproduc-
tion has been almost entirely. abandoned
for clean cutting and planting, the Ameri-
can student will see a form of ‘manage-
ment impossible under our conditions.
He will, however, have a chance to study
the most striking example that Europe af-
fords of the dangers and advantages of a
purely financial forestry. In Saxony, the
most remunerative- use of forests is the
growing of Spruée for paper pulp. The
diameter at which Spruce can be used
there for this purpose and its rate of
growth are such that it pays best to cut it
when it is about sixty years old. At this
age, however, European Spruce does not
bear full crops of seed, and natural repro-
duction under a rotation of sixty years is
impossible. It is thus that the system of
planting and sowing has come about, it
having been found financially preferable to
natural reproduction and a longer rotation.
The-system is the most remunerative in
Europe and there are Saxon forest ranges
which yield a net revenue of twelve to fif-
teen dollars per acre per annum. On the
other hand, it gives rise to dangers, from
insects and from wind which are suffici-
ently serious to render its advisability an
open question. The one is invited by the
raising of pure evergreen woods of one
species over large areas; the other by the
clean cuttings, under which trees grown
in closed woods become suddenly and
fully exposed. The measures enforced to
give the highest possible degree of safety
against these dangers are largely peculiar
to Saxony, particularly those which are
taken as a safeguard against wind. The
ranges are split up into a number of
what are called cutting series, each series
constituting an area which is treated sepa-
rately. Since the heavy winds in Saxony
are westerly, the object in the manage-
ment of these cutting series is so to lumber
them that the youngest woods occupy the
west and the oldest the east side. With
this in view, cuttings proceed always from
14 STUDY IN EUROPE FOR AMERICAN FOREST STUDENTS.
east towards west, with the result that the
closed forest is never suddenly exposed on
the west side. A normal ‘ cutting series,”
or in other words one in which there is a
regular gradation of woods of different
ages, presents a curious appearance and
consists of a series of even aged blocks ar-
ranged like the steps of a stairway, from
the youngest plantation to the mature
stand, and each protecting the other from
the wind. This elaborate precautionary
measure has one weak point. So long as
the heavy winds are westerly, it affords
an entirely adequate means of protection.
Now and again, however, a strong wind
comes from the east, when it is free to
work great havoc on the unprotected ma-
ture woods which bound the cutting series
on that side.
The Schwarzenberg forest district, hard
against the Bavarian border, contains some
representative forest ranges among which
are the most remunerative in the king-
dom.
Having seen the systems applied to the
mixed forests of the Schwarzwald and in
the pure stands of Spruce in Saxony, the
student will have had an opportunity to
compare the two great types of forest man-
agement in Europe. The painstaking,
patient methods by which reproduction is
obtained in the Schwarzwald and a high
degree of safety attained is in strong con-
trast to the Saxon system in which grave
dangers are invited by direct violation of
the silvicultural laws governing the natural
development of a forest.
It is a question whether the student will
find in Prussia, except upon the Pine Bar-
rens, many notable forms of forest man-
agement which are not quite as forcibly
illustrated in southern Germany. The
Prussian working plan method is the most
intricate of all and forest management
generally in Prussia is more hampered by
red tape than anywhere else in Europe.
He should not fail, however, to visit the
Salmuenster range in southwest Prussia,
where Oak is reproduced naturally in in-
structive contrast to the treatment of the
same species in the Spessart.
These are a few of the forest ranges
which Americans have found instructive.
To include them all would have been to
make a catalogue of this paper. The list
which has been given is suggestive only in
its purpose. Before one has been long in
Europe, he will be able to make his own
plan of campaign far better than another
can make it for him, The main point is to
weigh that plan thoroughly, and above all,
with a realization of the fact that European
forestry, although simple in purpose, is
intricate enough in its details to bewilder
any one who approaches it in a desultory
way.
It is also well to remember at the very
outset, that no man can master the details of
European forest management ina year, and
that the profit gained from the trip will de-
pend largely upon the selection made of
those features to be especially studied. The
American forest student will find scientific
research highly developed in European
forestry and he can waste a good deal of
his time over abstruse lines of investigation
which not infrequently owe their origin
solely to the yearning of a scientist to in-
vestigate something. He should never
lose sight of the fact that his main purpose
in going to Europe is to see the effect of
forestry upon the forest. The greatest
practical benefit to him lies in the study of
the woods themselves and of the working
plans under which they are managed.
The student who goes abroad for a year
had no time for a European forest school.
Should he spend an extra six months in a
semester at one of the several forest schools
in Germany, he will have an interesting
experience. However, one goes abroad to
get what he cannot get at home, and the
establishment of forest schools in this
country has done away entirely with the
necessity for students to attend them in
Europe. Before this was the case, the
forest school at Munich was most often
chosen by Americans. It has an eminent
corps of instructors, and Professor Henrich
Mayer, who handles silviculture and forest
utilization, adds to his remarkable bril-
liancy asa silviculturist an intimate knowl-
edge of American forests and American
conditions.
Living is proverbially cheap in Europe,
particularly in the villages and smaller
BOOK LIST. 15
towns. In those cases where the student
spends a month or more upon one range,
it is customary for him to pay a fe: of
twenty-five dollars per month to the forest
officer. No fee is asked for short visits to
forest ranges and the invariable courtesy
of European forest officials makes these
possible to anyone who bears the proper
credentials. One thousand dollars is suffi-
cient to pay all necessary expenses for a
year in the woods of Europe, and permits
of a fair amount of travelling. Less than
that sum would curtail one’s movements
‘somewhat undesirably.
BOOK LIST,
All books mentioned in this list will be sent post paid by the publishers upon receipt
of prices quoted.
A Primer of Forestry, Part I. Guir-
FORD Pincuor. Bulletin 24 of the Bu-
reau of Forestry, U. S. Department of
Agriculture. Part I. contains chapters on
‘““The Life of a Tree,” ‘*Trees in the
Forest,” ‘* The Life of a Forest,” ‘+ Ene-
mies of the Forest.”
Schlich’s Manual of Forestry. Pub-
lished in five volumes by Bradbury, Ag-
new & Co., Bouverie Street, London.
Vols. I. and II. are especially valuable to
a beginner. This can be imported for a
little over $12.00.
Elements of Forestry. F.B. Houcu.
R. Clark Co., Cincinatti. $1.50. One
of the few American books on forestry.
Good; though out of date in some re-
spects.
_ North American Forests and Forestry.
“ Ernest BRuNCKEN. G.P. Putnam’s Sons,
New York. $1.50. Expository in char-
acter, and written for the general reader.
The White Pine.
and H. S. Graves.
New York. $1.00.
The Adirondack Spruce. GiFFoRD
Pincuot. G. P. Putnam’s Sons, New
York. $1.00. This, like the ‘* White
Pine,” is a study of the habits and growth
of an important lumber tree and of its rate
of wood accretion per tree and per acre,
with conclusions drawn from this study as
to the financial possibility of practical
forestry in dealing with the species.
GiFFoRD PINCHOT
The Century Co.,
Practical Forestry in the Adiron-
dacks. H.S. Graves. Bulletin 26 of
the Bureau of Forestry, U. S. Depart-
In writing mention this pamphlet.
ment of Agriculture. Sold for 15 cents
by the Superintendent of Documents,
Union Building, Washington, D. C.
Working Plan for Township go. In
preparation. Will appear during the sum-
mer of rgor as Bulletin 30 of the Bureau
of Forestry of U. S. Department of Agri-
culture. A report making recommenda-
tions of the forest management of the
Township containing Racquette Lake in
the Adirondacks.
What is Forestry? B. E. Frernow,
Bulletin 5; Bureau of Forestry, U. S.
Department of Agriculture. Out of
print but should be in public libraries.
The Forest Nursery. G. B. Sup-
wortH. Bulletin 29, Bureau of For-
estry, U. S. Department of Agriculure.
Chapters on,‘ Collecting Tree Seeds and
Care before Planting,” ‘¢ Propagation of
Trees from Seeds and Cuttings,” ‘* Win-
tering and Planting Seedlings,” ‘Use of
Wild Seedlings,” ‘+ List of Useful Tim-
ber Trees to Plant.”
Manual of Botany. Asa Gray.
(6th edition.) American Book Co., New
York. $1.60; Pocket edition $2.00. A
key to the flora of the Northeastern
States.
How Plants Grow. Asa Gray.
American Book Co., New York. 80 cents.
An understanding of the way which a
tree grows is of the first importance to a
forester.
Illustrated Flora of the Northern
United States. 3 vols. N. L. Brirron
and A. Brown. $9.00 per set. A
16 BOOK LIST.
thorough and valuable guide to the flora
of the Northern part of the Continent.
Chas. Scribner’s Sons, New York.
~ Flora of the Southern States. A.W.
CuapmMan. American Book Co., New
York. $4.00. An excellent key to the
Southern flora.
Trees of the Northern United States.
E. A. Apcar. American Book Co., New
York. $1.00. rest, about 44 Ibs. of nitrogen;
Silver fir forest, ee Bb) ES re
Spruce forest, “ 33 6 « "
Scotch pine forest, “ 30 “ “ a
Thus, only the ammonium salts and the organic compounds of
nitrogen formed in the process of decay are available for the roots
as sources of nitrogen. The amount of nitrogen supplied to the
soil through atmospheric precipitation, either in the form of nitrates
or ammonia, is not sufficient to supply the needs of trees for nitrogen.
There remains still another source, and this is the organic com-
pounds of nitrogen formed in the process of decay of litter. In
fact, Ebermayer has recorded strongly developed roots of spruces and
firs on the Bavarian Alps that grew in pure humus one meter thick,
from which he concludes that the dark forest humus furnishes all
the nitrogen and other mineral nourishment required by trees.
If, therefore, the source of nitrogen in forest soil is nitrog-
enous compounds resulting from the decay of the litter, one would
expect in a forest which is managed on a business basis (that is,
in which trees are removed when ripe), a gradual decrease of the
contents of nitrogen in the soil, as occurs on a larger scale in agri-
culture. In agriculture, where the annual harvesting of crops de-
prives the soil of almost all the nitrogen which is assimilated by
the plants, and returns to the soil only a small part of it by the decay
of the roots of the plants, and where the easily soluble nitrates are
washed out by rains and carried away from the’ fields, or deposited
in layers inaccessible to the roots, the exhaustion of nitrogen in the
soil sets in soon, and the artificial introduction of nitrogen becomes
a necessity.
One of the most common ways of replenishing the nitrogen taken
up by crops is manuring and the growing of leguminous plants which
have the capacity of absorbing atmospheric nitrogen. These plants
are plowed under during the period of blooming, and when they
decompose they give their nitrogen to the soil. In the forest, it is
true, a considerable part of the nitrogen is returned to the soil in
the form of shed leaves, and only part of it, which is contained in
the trunk of the tree, is removed. The washing out of nitrates from
forest soil does not occur, because no nitrates are formed in it, and
those which are brought in by atmospheric precipitation are de-
composed under the influence of a special microorganism known
as Bacillus dentrificans, which is formed in soils with acid reaction.
But forest soil, though it loses less nitrogen than does arable
land, nevertheless loses it; and more remarkable yet, forest soils
not only do not become poorer in nitrogen, but, on the contrary,
439 POPULAR SCIENCE MONTHLY.
become enriched with it, a fact readily demonstrated in poor soils
planted to forests.
How this loss is compensated by nature was not known until
recently. The introduction of nitrogen into forest soils artificially
is not practicable, and therefore the enrichment of the soil with
nitrogen must go on under the influence of other causes. A cer-
tain number of leguminous plants grow in forests, but these are by
no means sufficient to compensate for the loss of nitrogen through
the felling and removal of forest trees. In some arborescent spe-
cies, as Alnus glutinosa, Robinia pseudacacia, and others, tubercles
which stimulate assimilation of free nitrogen are found on the roots.
It may happen that such species do not occur in the forest, or that
the necessary bacteria do not develop in the soil, when the loss of
nitrogen would not be replenished at all. This replenishing, how-
ever, always occurs, and some sources must be found to account for it.
Recently, E. Henry, professor in the forest academy at Nancy,
France, discovered a new source of enrichment of the soil with nitro-
gen, which is of great interest to foresters. Professor Henry has
proved by experiments that the loss of nitrogen in forest soil is con-
stantly repaired by means of absorption of atmospheric nitrogen by
fresh forest litter.
In November, 1894, Professor Henry collected leaves only recently
dead and still hanging on oaks and hornbeams (Carpinus betulus).
The amount of nitrogen in these leaves was determined in per cent.
of the dry substance. In this way it was found that the leaves of
oaks contained 1.108 per cent. of nitrogen, and the leaves of the
hornbeams 0.74% per cent. The oak leaves were placed in two
zinc boxes. The bottom of one of the boxes was covered with lime-
stone, that of the other with sandstone not containing lime. Both
boxes were covered with a netting of galvanized wire. The leaves
were dried in the laboratory, and 48.16 grams of their dry substance
were placed in the first box, and 53.54 grams in the second. The
leaves of the hornbeams were distributed in the same way. All four
boxes were exposed to air, with necessary precautions against enriching
the leaves with nitrogenous compounds. In December, 1895, the
following year, Professor Henry determined the contents of nitrogen
in the leaves taken from two boxes, whereby it was found that the
oak leaves taken from the box with the limestone bottom contained
1.923 per cent. of nitrogen, and the leaves of hornbeam taken from
the box with the sand bottom, 2.246 per cent. After making the
necessary allowance for loss in weight of oak and hornbeam leaves
owing to decomposition, Professor Henry computed the increase of
nitrogen in the oak leaves at 4 per cent., in the hornbeams at .78
NITROGEN IN FOREST SOIL. 440
per cent. Thus it was proved by him that fresh leaves fallen from
trees absorb atmospheric nitrogen in the process of decomposition.
The two other boxes remained exposed to the air for another
year, and in May, 1896, fifty grams of fine forest soil were added to
each box. On subjecting the leaves contained in them to a chemical
analysis, Professor Henry found almost the same contents of nitrogen
that had been found in the leaves of the first two boxes which were
exposed to the air during only one year. From these results he
concluded that the capacity of fallen leaves to absorb nitrogen from
the air is retained only in leaves freshly fallen on old litter.
The capacity of forest litter to absorb nitrogen develops probably
under the influence of special microorganisms, active only at the
beginning of the process of decomposition of fallen leaves; later,
however, when the process of decomposition of leaves goes on under
the influence of exclusively inorganic agents, no increase of nitrogen
i? observed; on the contrary, a loss is shown.
It is thus scientifically proved that forest litter is capable of
enriching the soil with nitrogen, but only under the condition that
the decomposition of freshly fallen leaves goes on. As to the assum-
tion that bacteria are developed in freshly fallen leaves, which, like
Ehizobium leguminosarum Frk., possess the capacity of absorbing
atmospheric nitrogen, it can only be said that as yet no bacteria
have been found in forest litter. :
A practical deduction from Professor Henry’s scientific investi-
gation is the advisability of planting cut-over areas as soon as possible,
so that the young seedlings may find in the soil a quantity of nitrogen
sufficient for their nourishment. The longer cut over areas remain
unplanted, the less is success to be expected from planting, as the
young trees develop poorly because of insufficient nourishment.
Thus, the forest not only furnishes timber and other products,
prevents snow- and land-slides, and regulates the flow of rivers, but
enriches the soil with nitrogen, one of the most essential nutritive
elements of plants, and in this way transforms poor soils, fit only
for tree growth, into rich agricultural lands.
A STUDY IN PLANT ADAPTATION.
By Proressorn J. W. TOUMEY,
YALE UNIVERSITY,
[Reprinted from PoputaR ScizncE MONTHLY, October, 1902.]
A STUDY IN PLANT ADAPTATION.
By Proressor J. W. TOUMEY,
YALE UNIVERSITY.
Hoo one interested in plants knows that they are very depend-
ent upon their surroundings. The atmosphere and soil con-
ditions that suit one species are often totally unsuited to another. In
the process of development the different species become structurally
and physiologically modified with the change of environment ; they take
on certain adaptions, where they succeed best, which particularly fit
them to their surroundings.
Every plant in order to grow must receive material from the outside
and must get rid of waste matter. The plant does not differ in any
essential respect from the animal in this regard. So also, the plant, in
order to continue from generation to generation, must bear offspring and
leave them in situations favorable to their growth.
In all seed-plants the food materials are essentially the same. The
ability of a plant, however, to avail itself of these materials depends
very largely upon a close correlation between the structure and the
physiological activities of the plant organs and its environment. Thus
a plant like the apple will not succeed in a hot and arid climate, while,
on the other hand, the date will not thrive beyond the limits of the
desert.
The sensitiveness of many plants to a slight change in soil or cli-
mate and the necessity for a perfect adaptation to a particular environ-
ment are illustrated in-the very restricted range of many of our native
trees and shrubs.
On the Pacific coast the Monterey cypress is only found growing
naturally over a strip of territory, south of the Bay of Monterey, about
t
484 POPULAR SCIENCE MONTHLY.
two miles long and two or three hundred yards wide, and over a still
smaller area a little farther south. The California fan-palm only oc-
curs in a few canyons of two mountain ranges in the southern part of
the state. The western hop hornbeam is only known to grow over a
few square rods of territory in the Grand Canyon of the Colorado river
in Northern Arizona. In eastern United States, Torreya only grows in
a narrow strip on the eastern bank of the Appalachicola River in
Florida; while the Florida yew, which grows in the same region, occu- '
pies a still less extended area.
Tn such cases as these it is likely that the structural and physiologic-
al adaptions of the different plant organs have not kept pace with the
natural changes in environment. As a result, these trees are not only
unable to extend their present range, but are poorly fitted to persist
where they now grow and consequently are disappearing. These old
types of trees have in the course of ages become inflexible and fixed and
are no longer in perfect accord with their environment. More modern
types, as illustrated in the various genera of Cactaceae, are more general-
ized and very readily take on structural and physiological modifica-
tions which fit them better to their present environment. It is inter-
esting to note that many of the species which appear to be out of accord
with their natural environment often do well under cultivation. The
gardener’s care in subjecting them to different environmental condi-
tions, particularly as regards food supply, seems to stimulate them and
give them new vitality, thus causing them to succeed better than more
modern types perfectly in accord with their natural environment. In
the latter case overstimulation, induced by cultivation, may from the
standpoint of vitality do more harm than good.
The Monterey cypress, although now nearly extinct as a wild plant,
is one of the most successful and easily cultivated trees of the Southwest.
It appears to be far better in accord with the artificial environment in-
duced by cultivation than it is with its natural environment. The
Franklinia of our gardens, a small tree first collected by John Bartram
in 1765 on the banks of the Altamaha River in Georgia, is successful in
cultivation, although as a wild plant it passed out of existence during
the past century. It is far more successful in cultivation than the
Loblolly bay, an allied species of the same genus which is now growing
wild from Virginia to Florida. The Ginkgo, an Asiatic tree of ancient
origin, grows remarkably well in cultivation, although at the present
time it is not known to grow as a wild plant any where.
Modern plant types that have not yet reached the limits of their
distribution and variation, as illustrated in many species of the Com-
positae, Rosaceae and Cactaceae, are so nicely adjusted to their natural
environment that cultivation often tends to diminish their vitality
rather than improve it.
A STUDY IN PLANT ADAPTATION. 485
It is not to be presumed that every variation in the structure of plant
organs is a direct result of adaptations taken on by the plant to protect
it from unfavorable factors in its environment. It is the natural, in-
herent tendency of plants to vary, and when the variation chances to he
in a direction that fits it better to its environment, the variation
is apt to persist in future generations. There is no apparent reason,
however, why in many instances structures may not be present in the
plant that are in no sense of direct aid. We should not expect to refer
every variation in plant structures to variation in environment. We
should, however, expect those species to do best that in their natural
Fig. 1. THE TUCSON PLAINS, SHOWING RANGE CATTLE IN THE DISTANCE 1 EEDING CPON
THE FRULL OF THE CHULLA.
tendencies to vary become so modified as to fit them most perfectly to
their surroundings.
Each plant organ must not only be adapted for the kind of work
that it has to do, but is must be adapted for doing its best under the ex-
ternal influences which enable it to persist in any given form. ‘The foli-
age leaf bears a definite relation to light and moisture; the leaves of
one plant, however, may have quite different requirements as to light
and moisture than the leaves of another. Every traveler in our arid
southwest has noticed that the leaves of the trees and shrubs are small
and thick, or, in some instances, entirely absent as foliage. The reason
for this is very clear. It arises from the necessity of the desert plant
to expose a comparatively small surface to the intense sunlight and the
desiccating action of the dry atmosphere.
486 POPULAR SCIENCE MONTHLY.
The various species of cacti illustrate this necessary correlation be-
tween plant structures and environment probably better than any other
large group of plants. Opuntia, the most important genus, is abun-
dantly represented in the flora of our arid southwest (Figs. 1 and 2)
and reaches its maximum development on the Tucson plains in
southern Arizona. No less than ninety-two species of Opuntia are
growing wild in southwestern United States and northern Mexico,
selecting for the most part situations that are so dry that few other
plants persist where they thrive.
In this article I desire in particular to call attention to the cholla
(Opuntia fulgida Engelm.) a cactus which grows to the size of a small
tree and which reaches its maximum development on the Tucson plains.
ro - ie os ae
Fig. 2. THE CHOLLA AND TUNA, GROWING TOGFTHER IN SOUTHERN ARIZONA.
The cholla has probably not yet reached the limits of its variation and
distribution, and is one of the most interesting and characteristic plants
of the arid regions of the western continent. The organs of this plant
are most wonderfully adapted for performing their various functions,
to the best advantage of the plant, under what would be with most
plants an extremely adverse environment.
The cholla is one of the largest of the cacti having numerous
branches. It grows best where fully exposed to the intense glare and
heat of the desert sun and where the annual rainfall averages from four
to twelve inches. It grows on the dryest upland, on open, porous, limy
soil that for months at a time is as dry as powder.
Where it grows best the summer temperature often reaches a maxi-
mum of 115 degrees F. and the daily temperature for wecks at a time ex-
A STUDY IN PLANT ADAPTATION. 487
ceeds 100 degrees F. during the hottest part of the day. Often for
several consecutive months there is no precipitation whatever and much
of the rain that does fall only penetrates the soil to the depth of a few
inches.
Not only is this cactus, as an individual plant, perfectly equipped by
nature to withstand and thrive under this extremely hot and arid
environment, but it is splendidly equipped for perpetuating itself by its
successful distribution of offspring under conditions which enable them
to succeed where on account of lack of moisture most plants would
perish.
The roots of the cholla do not penetrate to great depths in the soil
as one would at first thought suspect them to do. For the most part they
spread out a few inches under the surface. It would be useless for this
plant to send its roots to great depth into the soil, because only in rare
instances is there any available moisture there. As most rains only
penetrate the soil to the depth of a few inches the most moisture is
found in the surface soil. These surface roots of the cholla have a dif-
ferent structure from that found in the deeper roots and in the roots of
most plants. Their structure is splendidly adapted to enable them to
take up water with great avidity when the soil is moist and to survive
long periods of drought during which the surface soil is practically air
dry.
It would be of no special value to the cholla to absorb large quanti-
ties of water when available, if there were no provision made by the
plant for storing it, or if through transpiration it were readily given up
to the surrounding atmosphere. This cactus is not only remarkably
well equipped for storing water in large quantities, sufficient to carry
it through months of continuous drought, but it is able to retain this
water with wonderful tenacity, only giving it up to the hot and dry air a
little each day and taking advantage of each rain to fill its storage
tissue.
The structure of the young branches and stems of the cholla par-
ticularly adapts them for the storage of water in large quantities. At
the height of the growing season or after a prolonged summer rain the
stems of this cactus may contain as high as ninety-two per cent. of
moisture. During a prolonged drought the percentage of moisture very
perceptibly diminishes. The older stems and ‘branches which give
strength and support to the tree contain a much larger proportion of
woody tissue and consequently serve to a less degree for the storage of
water.
The ability of the plant to retain moisture results largely from the
comparatively small surface exposed to the dry air and the remarkably
thick epidermis and dense spine covering of the branches. The small
488 POPULAR SCIENCE MONTHLY.
surface is chiefly a result of the elimination of the leaves as foliage and
the contraction of the branches into thick, short stems as shown in Fig. 3.
During the growing season the cholla exposes to the atmosphere less
than one fiftieth of the surface
which is exposed by the maple of
equal weight here in the east.
Aside from this remarkable di-
minution of surface, the thick epi-
dermis of the plant almost precludes
transpiration at times when the
water in the storage tissues begins
to run low. The following illus-
trates how well the plant is adapted
for conserving the moisture pre-
viously stored in its thick stems.
I have cut a branch from the tree
in the spring prior to the season of
blooming, at a time when the stor-
| age tissue was well filled with mocis-
| ture. I have placed these branches
“Frc. a THE Suort, ‘THICK, SuccuLENE in a perfectly dry room out of con-
STEMS OF THE CHOLLA BEARING CLusters or tact with moisture. J have seen
ee them continue in growth, and
ultimately blossom. I have placed branches of the previous season’s
growth in open boxes without soil and without access to moisture early
in March, and in September have found the branches still succulent and
in condition to root and grow when placed in the soil.
Several years ago I removed a large specimen, having a trunk
diameter of eleven inches and a height of ten to twelve feet, from the
open mesa where it was growing to my garden. The tree was moved
in late May when in full bloom. Although the month was hot and dry,
the roots were closely pruned and the top left unpruned. The flowers did
not wilt as a result of this severe treatment and a full crop of fruit
ripened in the fall. This tree, which is illustrated in Fig. 4, suffered
no apparent harm in its removal, although probably fifty to one hun-
dred years old.
As a summary it may well be said that the cholla is admirably
adapted for absorbing water rapidly, storing large quantities of it, and
even when exposed to a very dry atmosphere for a long time retaining
it with wonderful tenacity. Provision is also made for undue loss of
moisture at times of injury to the epidermis, and the consequent direct
exposure of the storage tissue to the dry air. At such times a mucilagin-
ous substance contained in the cells appears on the injured surface,
quickly rendering it impervious to moisture.
A STUDY IN PLANT ADAPTATION. 489
It is probable that the thick covering of spines is of some value to
the plant in protecting it from the full force of the intensely bright
sunlight and also of some value in checking transpiration. These ever
present and formidable, barbed spines are well illustrated in Fig. 5.
They serve their greatest usefulness to the cholla in preventing its
destruction by animals and in the important part which they play in
the dissemination of the species. All the younger branches of the
cholla are soft and succulent and, were it not for their efficient armor
Fic, 4. A LARGE CHOLLA MOVED FROM THE MESA TO THE GARDEN.
of barbed spines, would be quickly destroyed by herbivorous animals.
In acquiring a condensed and succulent plant body in order to fit
itself to a desert environment the cholla would have courted its own
ruin were it not that it acquired a full equipment of spines at the
same time. From every standpoint it is, as an individual, admirably
equipped for its desert home. It is, however, more than this; it is the
best equipped of all desert plants for rapid and wide dissemination. It
makes ample provision for its offspring.
490 LOPULAR SCIENCE MONTHLY.
The seeds of the cholla, like those of several allied species, rarely
if ever germinate on the open mesa. In eight years of observation
in its center of distribution I never found a seedling of this plant
growing wild. It spreads almost entirely by vegetal dissemination,
i. ¢., by the ends of the branches becoming detached and transported
often long distances from the mother plant.
The cholla is perfectly adapted not only for the easy detachment of
the ends of the branches, but for their wide dissemination as well. The
fruit which hangs from the tree in long, pendulous clusters as illus-
trated in Fig. 6 is within easy reach of cattle and other large animals.
Fic. 5. WErRE It Nor FOR ITS FORMIDABLE ARMOR OF BARBED SPINES THE CHOLLA
WOULD SOON BE DESTROYED BY ANIMALS.
These clusters of succulent fruits are without spines and are for the
most part sterile. The fruit from the standpoint of seed production
is of very little service to the plant in aiding in its perpetuation and
dissemination. Its chief service appears to be to entice animals to the
plant that the fragile ends of the branches which become detached at
the slightest disturbance may adhere to them and become scattered far
and wide.
In order that these fruits may best serve their purpose they are
succulent, unarmed and as eagerly eaten by animals when green as when
ripe. Moreover they often remain on the plant for two or more years
if undisturbed. During periods of scanty forage in the region where
the cholla grows it is not an uncommon sight to see the range cattle
with their heads literally covered with these formidable cactus burs
A STUDY IN PLANT ADAPTATION. 491
which became attached to them in their effort to get the fruit. The
spine arrangement of these end branches or burs is such that when
they finally become detached from the animals transporting them and
fall to the ground, the lower end comes in contact with the soil. As the
roots start from this end of the branch the necessity for this provision
is very evident. It results from the spines being very short or wanting
on the lower end of the short, thick branches.
The special adaptation of the fruit to aid in vegetal dissemination is
confined, so far as J am aware, to a few species of the Opuntia and
reaches its highest development in the plant that I have described above.
TEs eT 5 7 7 z
Fic. 6. A GROUP OF CHOLLAS, SHOWING THE LARGE CLUSTERS OF PENDULOUS, SPINELESS
FRUIT. PHOTOGRAPHED BY W. T. SWINGLE.
The fruit of the cholla is probably changing from its original seed-
bearing condition to a condition of sterility. The abundant clusters of
fruit hang from the plant within easy reach of cattle and it is interest-
ing to note that since the advent of stock into the arid southwest the
cholla has become more widely distributed and more abundant than
orem befane Th in ae wall nominned by nature to care for itself and per-
w+ winds of the desert, as is the New England
bursts into foliage under April showers.
OBSERVATIONS
DE METEOROLOGIE FORESTIERE
FAITES A LA STATION DE RECHERCHES
DE
W’ECOLE NATIONALE DES EAUX ET FORETS
(1867-1899) .
PAR
M. RAOUL DE DROUIN DE BOUVILLE
GARDE GENERAL’ DES EAUX ET FORETS
’ (Extrait du Bulletin du Ministére de1’Agriculture. — 1901, n° 2)
PARIS
IMPRIMERIE NATIONALE
MDCGCCI
OBSERVATIONS
DE METEOROLOGIE FORESTIERE
FAITES A LA STATION DE RECHERCHES
DE
L’ECOLE NATIONALE DES EAUX ET FORETS
(1867-1899),
PAR
M. RAOUL DE DROUIN DE BOUVILLE,
GARDE GENERAL DES EAUX ET FORETS.
SS
Jv
La question de |'influence des foréts sur les nappes souterraines et les sources, qui,
depuis un certain nombre d’années, fait l’objet de nombreux travaux, a été mise a
Yordre du jour, en France, dés 1865. A cette époque, le maréchal Vaillant, dans une
lettre 4 M. Vallés, ingénieur en chef des ponts et chaussées, posait le probleme dans
les termes suivants: « Les foréts sont-elles une cause permanente de sécheresse ou d’hu-
midité? Favorisent-elles la naissance ou la pérennité des sources? Fournissent-elles a
ces sources plus d'eau que n’en donnerait un terrain cultivé en céréales ou en état de
prairie?..... Sont-elles une cause d’augmentation de la quantité d’eau de pluie qui
sinfiltre dans la terre et qui est utilisée, soit directement pour les besoins de la végé-
lation, soit pour la production et la conservation des sources?»
La réponse & cet appel ne se fit pas attendre; l'année suivante, l’administration des
Foréts faisait entreprendre, a 1'Kcole forestitre de Nancy, des recherches comparalives
sur Valimentation des nappes aquiféres souterraines, en terrain boisé et en terrain non
boisé. Cette alimentalion est due aux précipitations atmosphériques dont il est facile
d'apprécier importance, mais une partie seulement des eaux pluviales parvient jus-
qu’aux couches imperméables du sol. Pour évaluer 1a fraction qui approvisionne ainsi
les sources, il fallait connaitre préalablement celle qui se perd par ruissellement, éva-
poration, absorption par les racines des végétaux("),
Le probléme était complexe; il l’était méme trop pour qu’on tentat, au début, de ~
laborder sous tous ses aspects. Le programme des recherches dressé par M. Mathieu,
sous-directeur de 1’Ecole forestitre, ne comprit done que l'étude d’un petit nombre de
questions : — influence de l’état boisé ou déboisé du sol sur 1a quantité d’eau qu'il re-
coit de l’atmosphére, — proportion suivant laquelle le couvert des foréts intercepte la
pluie et !empéche de parvenir au sol, — marche de l’évaporation d'une nappe d’eau
sous bois ou hors bois").
Les observations ont été commencées en 1867. Elles ont fait objet, — en 1878 d'un
4 A V'époque ot ont élé commencées les observations, on n’avait pas pensé a relever, par des sondages,
le niveau de Ja nappe souterraine, comme I'a fait M. Ototzky, en 1897, dans les steppes de Russie.
®) Accessoirement, et dans un. ordre d'idées différent, a été entreprise l'étude des différences pré-
sentées par la température de I’air hors bois et sous bois. Il n’en sera pas question dans Je présent rapport,
M. de Drouin de Bouville. 1
—-t0( 2 )ea--
rapport de M. Mathieu, qui concerne les onze premieres années (); — en 1889 d'un
compte rendu de M. Bartet, inspecteur adjoint deg foréls, relatif 4 la période 1878-
1888 ®),
En 1899, il a paru inutile de continuer plus longtemps des recherches dont les ré-
sultats ont toujours été concordants; elles ont été closes le 31 décembre.
Le moment est venu de faire connaitre, d’abord, les relevés obtenus depuis 1889,
puis, les conclusions qui se dégagent de l'ensemble des observations, conclusions qui
sont d'ailleurs celles déja énoncées par M. Mathieu il y a vingt-deux ans et toujours
confirmées depuis.
Tel est Pobjet du présent travail, ob, conformément au plan adopté dans les mémoires
précédents, chacun des trois sujets éludiés fera l'objet d’un chapitre distinct.
I. — IneLuencE DE LETAT BOIS OU DEBOISE DU SOL SUR LA QUANTITE
D EAU PLUVIALE.
«Les précipitations atmosphériques sont-elles plus abondantes en forét, que si la
région était livrée a la culture agricole? C’est 1a une question tres controversée et d'une
solution trés diflicile, parce que le seul moyen rigoureus d’obtenir cette derniére serait
de comparer une contrée a elle-méme.sous {état boisé d'abord, sous I’état déboisé en-
suite, et que ce moyen est impraticable ©).
«Dans ces conditions, il a semblé possible d’approcher de la vérité, en comparant
entre elles deux localités, dont l'une serait boisée et l'autre déboisée, assez rapprochées
pour que les différences de latitude et de longitude ne pussent en modifier le climat
d'une maniére appréciable, assez semblables par le sol, le relief, l’altitude, pour que
ces circonstances fussent négligeables dans l'appréciation des phénomenes météoro—
logiques qui s’y produisent. I] était rationnel de penser que, si, dans ces localités exac-
tement comparables 4 tous égards, sauf 4 un seul, on constatait des différences dans
Ja quantité annuelle d'eau pluviale, elles devaient étre attribuées a l'état de la super-
ficie, au boisement ou a la nudité du terrain.»
La marche suivie par M. Mathieu se trouve, dans ces quelques lignes empruntées
a son rapport de 1878, a la fois exposée et justifiée.
Des emplacements convenables furent reconnus aux environs de Nancy; on installa
les observations continuées de 1889 a 1899 n’ayant fait que confirmer, sans plus, ies résultats déja acquis
et exposés dans les comptes rendus de M. Mathieu et de M, Bartet, ci-dessous cilds.
On comprend que, vu la possibilité d’apprécier quotidiennement [influence d'un massif boisé sur la
température de Yair, il ne soit pas ulile, pour arriver a formuler des conclusions, de prolonger les obser-
valions pendant de longues années. Il en va autrement en matiére de pluviométrie, vu Pirrégularité des
phénoménes étudiés.
() Météorologie comparée, agricole et forestidre. — Rapport a M. le sous-seerélaire d’Etat, président
du conseil d’administration des Foréts. Paris. Imprimerie nationale, 1878. (Avec atlas.)
(2) Météorologie comparde, agricole et forestiére. — Compte rendu des observations concernant Jes an-
nées 1878-1888. (Extrait dy Bulletin du Mimstére de Pagriculture). Paris. Imprimerie Nationale, 1890.
®) Ces observations ont pourlant pu étre faites dans les provinces centrales de I'Inde par Blanford. Un
terrain d’environ 61000 milles anglais, déboisé en 1875, fut, dopuis, reboisd sur Jes cing sixiémes de
son étondue. Dans 18 stations différentes, pendant que lo reboisement progressail, il y cut une augmen-
lation de chute de pluie d’environ 19 p. 100. (M. Henny, Les foréts ot les eaux souterraincs dana Ls
régions de plaine, p. 13. Nancy. Bergor-Levraull, 1898.)
—-t»( 3 )ee3-—-
dans chacun deux, en terrain découvert, un pluviométre de construction ordinaire, a
bassin de réception circulaire de 50 centimétres de diamétre.
La station forestitre fut établie aux Cing-Tranchées, au milieu d'un vaste plateau
boisé, 1a Haye. que forment les assises calcaires de loolithe inférieure; elle est élevée
de 380 metres au-dessus du niveau de la mer.
A la méme altitude, vers le sommet d'une colline de formation géologique sem-
blable, se trouve le village d’Amance, centre d'une région qui, sans étre dépourvue de
foréts, peut étre considérée comme plus spécialement agricole; ce fut emplacement du
second posle jusqu’en 1882.
A cette époque, des nécessilés de service le firent transporter 4 1a Bouzule, pres
Champenoux, dont Valtitude n’est que de 225 métres. Malgré cela, et aussi maleré le
voisinage de cantons boiss, les observations failes ont prouvé que la nouvelle station,
qui n’est située d'ailleurs qu’a 4 kilométres au sud-est de celle qu'elle a remplacde,
était soumise au méme régime pluvial.
Il parut utile, pour le contréle, d’établir un troisiéme poste, intermédiaire entre les
deux précédents; il fut placé & Bellefontaine, sur la lisitre orientale du massif fores-
tier de Haye, a laltitude d’environ 240 metres.
Les trois stations des Cing-Tranchées, Bellefontaine et Amance sont disposées & peu
pres sur une méme ligne, les deux derniéres se trouvent respectivement 4 6 et 17 ki-
lométres au nord-est de la premiére; la Bouzule en est distante de 19 kilométres,
dans la direction de l'Est-Nord-Est ),
Les observations, commencées en 1867, ont été poursuivies jusqu’en 1899 inclusi-
vement.
Les relevés mensuels relatifs aux deux premiéres périodes de onze années, 1867-
1877 et 1878-1388, ont été déja publics; il semble inutile de les reproduire ici; rest»
donc a faire connaitre ceux obtenus de 1889 4 1899. C’est l'objet des tableaux qui
suivent et qui concernent séparément chacun des trois postes d’observation.
Tapteau A. — Sration rorestibre pes Cinqg-TRaNncHkes.
a
INDICATION =
1889. | 1890. | 1891. | 1892. | 1993. | 1894. | 1895. | 1896. | 1897. | 1898. | 1899. ITOTAUX.) &
DES MOIS, 5
=
millim, | millim. | millim.|rillim. |millim. |millim.|millim.|millim.}millim.|millim.|millia.| millim. |millim.
Janvier....] 20.0) 93.0] 24.5) 79.6] 58.7] 37.9/135.3] 24.8] 26.9] 18.4/136.1] 654.5] 50.5
Février ...} 104.7] 4.4] —7.4]105.8] 94.4) 58.0] 14.7) 13.7) 74.9] 86.9] 15.8] 580.7] 52.8
Mars..... 57.5] 33.0] 62.9} 50.3) 17.0] 40.6) 87.6/126.9/100.5} 59.3| 31.9) 667.7) 60.7
Avril......| 59.5] 58:3) 51.91 35.01 #7 | 40.3) 30.1] 47.6] 84.9! 56.0]129.9] 599.8! 53.9
Mai. .....]102.6]108.0] 90.8} 31.3] 31.9] 49.7] 71.5] 36 3] 24.9/119.5) go.g] 756.0; 68.7
Juin....../137.0| 38.0]170.1] 89.8} 48.5} 57.4) 93.6) 78.3!191.7| 5.9] 54.8) g4o.t} 86.3
Juillet....) 64.3) 110.9] 97.4]132.0] 94.3] 61.4) 81.3) 80.5] go.9] 68.7] 92.3] 974-0] 88.5
Aott...... A1.9) 135.1] 64.7] 68.4) 38.1) 89.4) 68.1) 98.9/145.3)100.9] 75.6] 848.4) 77.4
Septembre.| 76.6] 17.8] 54.6) 80.4) 55.5{126.4] 6.3/136.11 78:7| 9.2/109.0] 750.6] 68.9
Octobre...) 111.1) 80.4} 89.6/191-1/191.7] 69.0/107.8/188.9] 8.1] 56.0) 66.1] 1089.8] gg.1
Novembre..| 39.5|129.7| 85.9) 54.1} 81.6] 32.8/130.8] 26.6) a4.2] 57.0} 23.2) 684.8! 69.3
Décembre..{ 43.3] 5.0] 98.3] 70.6) 54.4) 58.0/143.0| 86.6] 56.0] 40.0} 79.8) 735.6] 66.9
Toravx. . | 857.3 | 813.6 |898.11988.4)695.4)713.2/970.1 875.2|835.6 731.8/905.4) g284.1/844.0
{ Voir a Ia fin la carte des environs de Nancy donnant !emplacement des postes d’observation.
1.
—+9( A )ser—
Tasteau B. — Station ronestizne DE BeLLEFONTAINE.
SES RN SS
Ki
ee 1889. | 1890. | 1894. | 1892. | 1893. | 1894. | 1895. ] 1896. | 1897. | 1898. | 1899. |TOTAUX)
DES MOIS. ; ; a
=
millim. | mijlim. | millim.| millim. | millim.|millim.|millim.|millim.|millino.|millim.|millim.| oillim. |miltin
Janvier....| 8.0] 74.4] 53.9] 62.0] 44.8] 39.1] g7.a) 15:5) 15.2/ 14.7/190.2) 517.9] 47.4
Féveier....| 86.0] 6.3] 5.0] 75.2] gg-4} 55.3) 15.4) 11.8] 65.8] 89.0] 25.0) 527-2) 47.981
Mars..... 59.4) 33.5] 58.5) 36.7) 19.6] 39.7] 87.5[114.5) 82.0) 44.0) 28.5] 589.9) 53.6
Avril...... 5a.1] 55.1] d4a.2} 24.6] « | 45.0] 34.1] 46.5) 74.3) 53.8)194.1) 551.8) 5o.a
Mai. ..... 57.3| 82.0] 81.8] 27.2) 39.7} 45.3] 63.8) 18.3) 29.5)120.8] go.8) 649.5] 59.0
Juin...... 99-9] 41.9]108.7] 84.1| 63.2] 69.0} 86.4) 62.1/117.0] 65.7] 42.1) 840.1] 76.4
Juillet ....) 44.4) 95.6} 75.5]196.1} 91.3) 51.7] 67.0] 88.1] 73.8] 62.7| 92.6] 868.8) 79.0
Aott...... 4a.o]117.5| 62.8] 54.3) 40.3) 94.4) 64.5] 31.1)131.1] 75.6] 71.9) 765.5) 69.6
Septembre.| 92.5] 16.7] 50.3] 70.6} 54.4/109.3) 5.5j120.9) 78.7} 11.1/118.9] 721.9) 65.6)
Octobre...| 85.2] 81.1 |..82.5/189.7/123-2| 62.9/106.9/177-4] 4.7) 57.4) 62.2] 1032.5] 93.9
Novembre..| 37.2] go.1] 82.1] 41.4) 76.g) 30.8/199.1) 16.8) 93.3) 56.4) 99.5] 599.6) 54.5
Décembre..} 34.0] 3.0] 93.4] 57.8] 53.7) 49-0]/141.2] 70.5] 60.0] 35.8] 78.0] 676.4} 61.5
Toranx. . | 691.0] 697-2 | 776.5/849.9|692-5/657.5|/890.9|773.5/795.4)680.0/876.7) 8341.11758.3
Tasreau GC. — Station acricore pe La Bouzore.
n
INDICATION z
1889. | 1890. | 1891. | 1892. | 1803. | 1894. | 1895, | 1896 | 1897. | 1898. | 1899. |TOTAUX.| &
DES MOIS.
=
millim. | millim. | millim.|millim.|millim.|millim |millim.|millim.|millim. |millim./mallin.| millim. |millim.
Janvier....} 14.0] 64.4] 29.0] 41.1} 33.1] 20.7] 49.5) 19.9] 6.1] 10.4)112.0] 386.9] 35.1
Février,...] 72.4) 9.3) 2.4) 55.4] 78.5) 43.5) 13.5) 5.3) 39.5) 997.1) 16.5) 351.6] 32.0
Mars..... 44.9] 25.0/ 53.9) 15.6} 10.0] 30.6] 49.5) 96.5) 30.1) 20.0] 19.1) 394.5] 35.9
Avril...... 53.3] Ad.g| 34.7) 19.1] “9 | 41.9} 26.3) 98.4) 61.6) 37.8/114.6) 460.9] 41.9
Mai...... 44.5] 72.2] 59.9) 16.6) 25.9] 55.4) 38.9) 2.4) 29.6) 88.1] 50.4) 483.9] 44.0
Juin...... 99-8] 99.1] 63.8) 79.4) 59.0) 39.9) 89.1) 54.5) 66.4] 34.1] 99.8] 616.2] 56.0
Juillet .... | 49.8) 91.6] 66.7) 58.4} 68.9) 51.0) 47.0) 86.5) 73.7] 58.3] 97.8] 749.2} 68.1
Aout......| 38.8/116.1] 69.9) 54.0| 24.9] 41.4) 64.7) 79.9]/129.6] 72.7} 86.4] 769.3] 69.9
Septembre.| 43.8) 4 53.7| 73.6) 25.4) 63.9} 8.2/103.9] 70.1] 19.6] 73.2] 52a7.7} 48.0
Octobre...| 74.3] 85.7} 100.0]167.5] 99.3) 71.9} 71.6/119.5] 9.11 43.9] 50.8] 899.7} 81.1
Novembre..| 23.2] 95.8] 79.5] 35.3] 61.1} 34.7] 98.6] 16.6} 14.3] 53.4) 18.4) 530.9] 48.2
Décembre..} 24.9) 2.3] 73.4) 26.1} 39.0) 39.5]194.2] 56,0) 40.2] 26.9) 71.5/ 516.6] 47.0
Toraux. .|589.0 | 629.2 | 672.2}635.1/505.4/539.5/674.1/661.5/570.3)484.1/733.3] 6679.7/607.9
Les résultats sont plus apparents, si on dispose 4 cété les uns des autres les totaux
annuels des diverses stations. Le tableau suivant, ot ils sont ainsi rapportés, embrasse
@ailleurs la période tout entitre des observations, ce qui permet de formuler les.
conclusions générales qui s'en dégagent. Ce tableau donne les quantités absolues d'eau
pluviale regues par chaque poste; en outre, pour rendre les comparaisons plus faciles,
ona indiqué quelle serait, en ramenant a 100 millimetres la hauteur de l'eau recueil-
lie annuellement au pluviométre des Cinq-Tranchées, I'épaisseur correspondante de
Ja lame a Bellefontaine et 4 Amance-la-Bouzule.
—+o( 5 )-ca-—
Tasceau D. -— Quantités pEAU RECUES ANNUELLEMENT, EN TERRAIN DECOUVERT,
DANS CHACUNE DES TROIS STATIONS”,
a a
QUANTITES ABSOLUES, QUANTITES RELATIVES.
ANNBES. AMANCE, amancr, | OBSERVATIONS.
LES CINQ- | BELLK- LES CINQ- | BELLE-
TRANCHEES.| FONTAINE. oy TRANCHEES .| FONTAINE. el
millim. millim. | willim. millim. millim. | millim.
1867s ocet seeds 925.0 879.0] 862.0] 100 95.0 93.2
1868......... 748.0 738.0] 631.0] 100 98.7 84.4
1869......... 774.0 721.0] 628.0] 100 93.2 81.1
ABT0 eases cores 576.0 593.0] 518.0 100 103.0 89.9
1871 osc ie aceae 744.0 708.0] 625.0 £00 gb.2 84.0
1872) sacnewae 3 903.0 877.8] 717-0 100 97-2 79-4
1873......... 793.9 740.9] 639.0 100 98.3 84.8
1874........ ; 695.5 618.9) 545.9 100 89.0 78-5 \ La station acacia wet
1B 3B is vase ees oa 954.4 894.2} 597.2 100 93.7 62.6 a Amance.
1876. cesses 822.0 847.4] 669.9] 100 103.1 81.5
1ST To eisaies g21.4 961.9] 746.9] 100 104.4 81.4
1878. ese ces 1052.7] 1026.7, 825.8 100 97-4 78.4
1879 sce eee e 998.2} 979-2| 726.9 100 98.1 72-9
1880.......5. 877-1] 870.7] 678.9] 100 99:3 77-4
1881... ..... 682.9) 736.8) 514.3; 100 108.0 79.3
1882 6s wove. 973.7| gha.g} 822.6] 100 96.8 84.5
1883......... 878.5 916.1} 680.9 100 104.3 77°5/
1884......... 668.9] 626.6) 559.7) 100 93.7 83.7
1885......... 1009.2 814.7] 763.0 100 80.7 75.6
1886......... 930.7] 891.1] 738.0] 100 95-7 79.3
1887 esi cease 772-91 720.2} 577.0] 100 g3.1 74.7
1988). ise2 aie 1061.0] 849.2] 723.6} 100 80.0 68.9
1889......... 857.3] Gg1.0) 582.0 100 80.6 67.9 i
1890......... 813.6] 697.2] 629.2] 100 85.7 77:3 i wisieon iene
VBE ees ce ee 898.1 776.9 672.2 100 86.5 74.8 4 La Bouzule.
1892......... 988.4} 849.9) 635.1 100 86.0 64.3
1893......... 695.4] 692.5} 5obd.4 100 99-6 74.0
1894 ss ewe cees 713.2} 6597.5) 432.5) 100 92.2 74.7
1895. ceases 970.1} 890.9] 674.1 100 g1.8 69.5
1896......... 875.2] 773.5) 661.5] 100 88.4 75.6
1897......... 835.6] 755.4) 5470.3] 100 88.5 | 68.1
1898......... 731.8] 680.0) 484.1 100 92-9 66.9
1899......... go5.4| 876.7] 7383.3] 100 96.8 81.0
Toravx...... 28006.1 | 26295.4) 21470.3 4 4” "
Moyernes.... 848.7} 796.8] 650.6 100 93.9 76.7
{) Voir & Ja fin le tracé graphique représentatif de re tableau.
—--tm( 6 )eea--—
On voit que, sans aucune exception, pendant toute la durée des observations, la
station agricole a regu sensiblement moins d’eau que les stations forestiéres. De plus,
huit fois sur dix, la pluie a été plus abondante au poste des Cing-Tranchées, situé au
centre du massif de Haye, qu’a celui de Bellefontaine, établi sur a hisiere.
Ce résultat, déja signalé en 1878 et 1889, ne saurait, fait remarquer M. Mathieu,
étre effet du hasard: c'est, au contraire, la conséquence d’une cause permanente,
qui, dans les conditions ot l'on s'est placé, ne peut étre que I’état superficiel du sol,
trés boisé dans deux stations et découvert dans la troisieme.
Mais est-il permis de conclure des observations, d’une fagon générale, que les foréts
ont pour effet d’accroitre la proportion des eaux météoriques qui tombent sur une
contrée?
Ici se présente une objection. C’est a Est du plateau de Haye que se trouve la région
d’Amance-la-Bouzule; il est démontré qu'elle est moins arrosée que la forét; mais en
serait-il de méme en cas de changement. dans la siluation respective des contrées étu-
diées ?
Pour répondre atone maniére précise, il faudrait pouvoir établir tout autour de la
forét des stations agricoles. Ceci suppose un massif isolé au milieu d'une région dé-
boisée, situation qui ne se rencontre pas aux environs de Nancy.
Dans les conditions oi ont été faites les observations, il est donc naturel de se de-
mander si les résultats obtenus ne sont pas dus uniquement 4 ce que Amance-la-
Bouzule se trouve a Est du plateau de Haye. La chose serait d’autant plus vraisem-
blable qu'il pleut surtout par les vents d’Ouest. Alors les différences constatées entre
les deux postes liendraient seulement A Ja distance qui les sépare, ou A cette circon-
stance que les nuages de pluie passent au-dessus du massif forestier avant de parvenir
ala région non boisée.
Ii est possible, cependant, bien que la station agricole soit unique, de mettre en
évidence l'influence de la forét et de se rendre compte des conditions dans lesquelles
elle s’exerce. On y arrivera, en comparant séparément, pour chacun des vents par les-
quels se sont produites les précipitations atmosphériques, les quantités d’eau tombées
aux Cing-Tranchées et 4 Amance-la-Bouzule
Toutefois, il ne semble pas utile de pousser tres loin ce détail. Si les résultats ob-
tenus sont dus & la situation relative des postes d’observations, des différences se fe-
ront sentir, si on considére, d’une part, les cas ot les nuages pluvieux vont de la
forét 4 la contrée dénudée; d’autre part, ceux od ils viennent de toutes autres direc-
tions.
Or le massif de Haye, qui se prolonge vers le Nord par celui de YAvant-Garde et
les bois de Liverdun, est disposé de fagon 4 abriter en quelque sorte Amance-la-Bouzule
contre les venls d'entre Nord-Ouest et Sud-Ouest. De 1a, 1a répartition faite dans le
tableau ci-aprés. Faute de renseignements pour fa période antérieure 4 1889, on
n'a pu y faire figurer que les relevés concernant les onze dernigres années :
Tasnzau E. — Comparaison ENTRE LES QUANTITES DE PLUIE TOMBEES
PAR LES VENTS DU SECTEUR OvEST ET CEUX DES AUTRES SECTEURS.
VENTS YES beovaad
, DU QUANTITES TOTALES
po ee :
= -0.- .N.E.-B.-E.N E.- DE PLUIE TOMBEE.
S.0.-0.5.0.-0.-0.N. 0. etN.0. §.E.-S. §.._8.-§. 5.0.
LES CINQ= L85 GING- LES CINQ-
es ‘¢mancuées, La BOUZULE. iavaea den LA SOUZULE, peencn tea 1 LA, BOUZULE.
ANNEES, ’ .
Hautear | , 4 Hauteur . | Hauteur
Epaisseut Epatsseur corres- Epaisseur | Mpaisseur | corres- Kpaisseur Epaisseur corres-
de de pondant de de pondant de de pondant
la Jame ja lame a ee Ja lame la fame a sage la lame la lame 7 ae oh
desu d'eau {too millim. d'eau @eau |1oomillim.} d'eau @eau {100 millim.
annuelle. | annuelle. a annuelle. | annuelle. Cae annuelle. | annuelle. ao
millim. millim, millim. tillin. millim, | millim. millim. millim. millim.
1889....] 629.3] 395.4] 62.8 298.0| 186.6} 81.8 857.3] 58a.0] 67.9
1890....| 552.0] 436.1| 79.0 261.6] 193.1] 73.8 813.6] 629.0] 77.3
1891....] 621.5) 390.9) 62.9 276.6 | 281.3} 101.7 898.1] 679.9] 74.8
Y1892....]) 698.3, 441.5} 63.7 ag5.1| 193.6] 65.6 988.4] 635.1] 64.3
4893....] 373.9] 287.7] 77-4 392.9] 917.7] 67.6 695.4) 505.4] 74.0
1894....| 561.1] 393.9] 7o.1 152.1] 139.3] 91.6 713.0) 531.5) 74.9
1895....} 459.0] 333.4] 73.8 518.1] 340.7{ 65.8 gj7o-1| 674.1] 69.5
1896....] 501.0) 419.6} 83.7 374.1] 2hi.g}| 64.7 875.2] 661.5] 75.6
1897....] 554.9) 414.4) 7.9 280.7] 155.9] 55.7 835.6} 570.3] 68.1
| 4898....] 367.4) 278.0} 75.9 364.4) 206.5} 56.6 731.8) 484.1 | 66.2
1899....] 5a4.9]° 466.8] 88.9 380.51 266.5} 76.0 go5.4] 733.3| 81.0
Toraux...| 5830.7} 4257.0} 4 3453,4| ohe9.4 " g284.1 | 6679.7 a" \
| Movennss.| 530.1 387.0| 73.0 313.9] 220.9] 70-1 84h.o Go7.2 | 71.9
. s |
Il résulte, de la concordance des chiffres précédents, que, dans toutes les circon-
stances, il pleut plus abondamnieut aux Cing-Franchées qu’a Amance-la-Bouzule; de
plus, le rapport entre les quantités d'eau recueillies est indépendant de la direction du
vent. Il ne peut donc étre question d’expliquer le fait par la situation du second poste,
plus dloigné que le premier du point de Thorizon d’ou arrivent ordinairement les
fiuages de pluie. La forét a, par conséquent, une action réelle sur l’abondance des
précipitations atmosphériques; elle a le pouvoir de condenser les vapeurs contenues
dans Yair et d’augmenter sensiblement la quantité d’eau météorique tombant sur la
région qu'elle oceupe. L'accroissement, par rapport 4 une contrée agricole voisine, est
dailleurs le méme, quelle que soit la position relative de cette derniére.
Liinfluence du massif boisé étant ainsi établie, il est intéressant de voir si elle ne
s'exerce pas d'une facon différente quand les arbres sont couverts de leur feuitlage et
Jorsqu’ils sont dénudés. Une comparaison entre les quantités de pluie tombées respec-
tivement pendant ja saison de végétation, c’est-a-dire de mai a septembre, et pendant
le reste de l'année, va permettre de sen rendre compte.
4
—+%( 8 )s¢3---
TABLEAU F, — CoMPARAISON ENTRE LES QUANTITES DE PLUIE TOMBEES
PENDANT LA SAISON FROIDE ET LA SAISON CHAUDE.
PERIODE DE VEGETATION. PERIODE DE REPOS.
MAI-SEPTEMBRE. OCTOBRE-AVRIL.
LES CINQ- LES CINQ-
es AMANGE, La BOUZULE. - AMANCE, LA BOUZULE.
TRANCHEES. TRANCHEBS,
ANNEES. Hagieur Hauteur | OBSERVATIONS.
Epaisseur Epaisseur corres~ Epaisseur Bpaisseu : corres- :
de de pondant de de pondant
4 une chule & une chute
Ja lame ja lame de Ja lame la Jame de
deau deau 100 millim. dean dean 100 millim.
recueiflie. | recueillie. oe recueillie. | recueillie. ee
millim. millim, willim. millim. millim. millim.
1867......... 310.0; 297.0 | 73.2 615.0 635.0 | 103.3
1868....... ‘ts 192.0 190.0 | 99.0 556.0 4b1.0| 79.2
1869......... 368.0} 250.0 | 67.9 4o6.0 378-0] 93.1
1870......... 235.0 209.0 | 88.9 341.0 309.0] 90.6
LST siseee ais eg 378.0] 312.0 | 82.5 366.0 313.0] 85.5
DS These cca see 335.9] 261.8 | 77.9 567.1 455.2] 80.3
18734 ois ee ve - 3805] 322.5 | 84.8 373.0 316.5] 84.8
DOTA one emcees 302.0 275.4 | 91.2 393.5 270.5] 68.7 La station
VB TD semnaetie s 591.3] 279.7 | 52.3 432.8 324.5 | 75.0 agricole
VIB crass ss ~.] 8a7.4] 243.3 | 74.3 hgl.6| 426.6] 86.3 eek 2 Ainiaaes,
1877....... « 371.7; 279.8 | 75.3 549.4 467.1] 85.0
IST8 seis fas hahg 349.7 | 82.3 627.8 476.1} 75.8
1979 oy eae 491.5 4o6.2 | 82.6 506.7 320.7] 63.3
1880......... 315.7] 997.9 | 72.2 561.4 451.0] 80.3
1881. .ccse.es 318.3 213.6 | 67.4 364.6 300.7| 82.5
1882s icace dens 519.6] Aah.o | 81.6 ADA. 398.6} 87.8 |
1883......... 381.8] 345.5 | 89.0 hgo.4 335.4] 68.4
1884... acne 275.4 261.9 | 95.0 393.5 297-8) 75.7
1885......... 362.8 288.3 | 79.5 646.4 Aqh.g | 73.4
1886). esa ee ss 438.4} 354.5 | 80.9 4g2.3 383.5] 77.9
1887 se seaesces 393.1 289.1 | 71.8 379.8 2g4.g} 77.6
1888......... 547.9] 390.7 | 71.3 513.1 332.9] 64.9
ee hor.7| 296.7 | 65.6 435.6} 305.3] 7o.1 ey
1890......... hog.8 309.0 75.4 403.8 320.2 79.3 est & Ja Bouzule.
TBO bee eie a nine o 477.0} 306.3 | 64.1 420.5 365.9 | 87.0
18926 sca 8 sah ho1.g 275.0 | 68.4 586.5 360.1] 61.4
LS 267.6 196.4 | 73.4 4o7.8 309.0] 7a.
TS OA pak ence 377.3 350.9 | 66.3 335.9 282.3] 84.0
WSO 5 6 sears aces - 320.8 aho.g | 75.1 649.3 433.2] 66.7
1896......... 360.1] 326.5 | 90.7 515.1 335.0] 65.0
1890 ees eicwens 460.8] 369.4 | 80.9 374.8 200.9| 53:6
1898 6c oe sates 358.0] 265.8 | 74.9 373.8 918.3] 58.4
1899......... hoa.6 330.1 78.4 489.8 4o3.2} 83.5
Toraux...... 12476.7 | 9534.9 a 15530.4 | 11936.1 a
Movennes.... 378.1 288.9 | 76.4 470.6 361.7] 76.9
REE REA NE RY PL
—t+( 9 j-er—
Contrairement a ce qui semblait se dégager des observations faites de 1878 a 1888,
it n’y a done pas de différence appréciable dans I’action de la forét en hiver et en été;
les moyennes se trouvent étre 4 tres peu prés les mémes pour chacune des saisons).
Un dernier point reste a examiner. I] a été démontré que la direction du vent et la
différence des saisons n’influaient pas sur le rapport entre les quantités de pluie
respeclivement regues par la forét et 1a contrée agricole. Mais ce rapport n’est-il pas
susceptible de variations avec l'abondance des précipitations atmosphériques?
Ii suffit, pour s’en convaincre, de faire porter les moyennes, non sur Ja durée en-
titre des observations, mais séparément, sur trois groupes comprenant chacun onze
années, savoir : les moins pluvieuses, — celles qui l’ont été moyennement, — celles
enfin od il a beaucoup plu.
Tasteau G. — VaniaTIONS, SUIVANT L°LMPORTANCE DES CHUTES DE PLUIE, DU RAP-
PORT ENTRE LES QUANTITES D’EAU RECUES PAR LES STATIONS AGRICOLES ET
FORESTIERES.
QUANTITES ABSOLUES. QUANTITES RELATIVES.
ANNKES. AMANCE, Amance, | OBSERVATIONS.
LES CINQ- | BELLE- LES CINQ- | 82LLE—
A
rrancuéss.| rosraine.| enancudes.|rowraise.|
"| BOUZULE. BOUZULE.
millim. nillim. millim. mil'im. milli. millim.
1888......... io61.0| 849.2] 723.6 100 80.0 68.9
1878 252000 9% 1053.7] 1026.7] 825.8 100 97-4 78.4
18853 cies sees 1009.2 | 814.7] 763.0 100 80.7 75.6
1899). ie aceite 998-2] 979.2] 726.9] 100 98.1 72.9
BOD eee cao seats 988.4) 849.9} 635.1 100 86.0 64.3
1882......... 973-7] g42.9} 822.6 100 96.8 84.5 ) Annéos trés pluvieuses.
1895.......-. 970-1 | 890.9] 674.1 100 91.8 69.5
1875.....--4 i gd4.1{ 894.2] 597.2 100 93-7 62.6
1886). 65 ne eas 930.7} 891.1] 738.0 100 95-7 79:3
1867. ses sere oe y25.0}| 879.0] 862.0 100 95.0 93.2
TST sence eussessry gait] gbs.g] 746.9 100) | 104.4 81.1
Neen 10784.3 | 9979-7 | 8115.2 u " ”
Pariineinscx 980.4} go7.2] 737-7. 100 g2.0 | 7b.a
) Météorologie comparée, agricole et forestiére. — Comple rendu des observations concernant les onze
années 1878-1888, par M. Bartet, p. 8.
) Le trés faible excés (0.05 p. 100), pendant I'hiver, est di probablement a Ja condensalion des va-
peurs de brouillard, plas abondante en forét qu’en terrain découvert.
M. de Drouin de Bouville. 2
—#3e( 10 Jees——
SEES
QUANTITES ABSOLUES. QUANTITES RELATIVES.
ANNNES, Les cinq- | netne- | AMANCE, | res cinq-| pente- | AMANCE, | OBSERVATIONS.
LA
TRANCHLES.| FONTAINE. ee TRANCHEES.| FONTAINE.| gouzoce.
millim. millim, millim. millim. willim. millim.
1899. .....605 go5.4 876.7 | 733.3 100 96.8 81.0 |
1872 ws sase-ai 903.0 877-8| 717-0 100 97-2 79-4
BOW swisseaveete ae 898.1 776.5] 679.2 100 86.5 74.8
1883 %.026 20545 878.9 916.1} 680.9 100 104.3 79.5
1880........- 877-1 870.7| 678.9 100 99.3 77-4 | ans
1896......... 875.2 973.5] 661.5 100 88.4 75.6 oa |
1889......... 857.3 691.0] 582.0 100 80.6 67.9
1897.......-. 839.6 755.4| 570.3 100 88.5 68.1
T8716 se sarees ais 823.0 847.4) 665.9 100 103.1 81.5
1890......... 813.6 697-2] 629.2 100 85.7 97-3
1869......6.. . 774.0 721.0} 628.0 100 93.2 B11
ToTaux.....« 9439.8 | $803.3 | 7223.9 " " u
Moyvenngs.... 858.9] 800.3] 656.7 100 93.3 76.5
LBS Ts asa owe 979.9 720.2) 577.0 100 93.1 74.9
1878. ....005- 793.5 qho.g| 639.0 100 98.3 84.8
1868....-...- 748.0 738.0| 631.0 100 98.7 84.1
VST scm na we qhh.o 708.0| 625.0 100 95.2 84.0
TSOS. cee xoeas 731.8 680.0] A&4.s 100 92-9 66.2 “|
PEGA ices ste si 713.2 657.5 532.5 100 92.2 74.7 Années peu pluvicuses.
187A. ewe o ae 695.5 618.9] 545.9 100 89.0 78.5
1893......... 695.4 692.5] 405.4 100 99-6 7h.o
1881 o. gca tees 682.9 736.8] 514.3 100 108.0 75.3
1884......... 668.9 626.6) 559.7 100 93.7 83.7
TST. oetacaine sa 576.0 598.0] 518.0 100 103.0 89.9
Toraux...... (7782.4. | 7519.4) 6131.9 ” 4” "
Moyennes....| 707-5 682.9] 557.4 100 96.5 78.8
:
Un fait semble se dégager des chiffres fournis par le tableau qui précéde, c’est que
dans les années séches, si les terrains boisés regoivent encore sensiblement plus d'eau
que ceux qui ne le sont pas, la différence s’alténuc quelque peu.
Des observations qui viennent d'étre étudiées et discutées, il est maintenant pos-
sible de tirer une conclusion générale et définitive sur l'influence exercée par les foréts
sur les chutes de pluie: elles ont pour effet d’en accroitre notablement limportance
et sont par suite favorables, de ce chef, & lalimentation des nappes souterraines et
des sources. Le rapport entre 1a quantité d’eau tombée sur un massif et celle recue par
ua point quelconque de ja région agricole environnante est d’ailleurs une quantilé
constante qui est la méme I’hiver et Pété; elle augmente et diminue seulement entre
des limites rapprochées, avec labondance des précipitations atmosphériques.
/ Les résultats obtenus & I'icole forestitre concordent avec ceux de quelques obser-
vateurs, tant francais qu'étrangers ), dont les travaux n’ont d’ailleurs pas élé pour-
suivis pendant, aussi longtemps. Ces résultats n’en sont pas moins exposés Ala critique,
vu Ja défectuosité d'une installation quin’a pu comprendre que deux slations altitude
(©) MM. Fanteal, pris de Senlis; Ebermayer, en Bavidre.
tee 11 jer
égale, il est vrai, mais séparées par une dépression de 80 métres de profondeur (”),
Recommencer les recherches serait donc encore utile, d’autant plus que, si l’action de
la forét est connue, il reste 4 en faire une étude plus précise et détaillée; on peul
chercher & savoir, par exemple, jusqu’d quelle distance de la lisiére elle se fait sentir
et suivant quelles lois varie son intensité 4 lintérieur du massif. Une nouvelle série
d’observations entreprises dans de bonnes conditions) et continuées pendant une
vingtaine d’années serait donc fort & souhaiter, tant pour 1a confirmation de ce qui
est connu que pour la découverte de ce qui ne l’esl. pas encore.
,
I]. — Quanrité EAU PLUVIALE INTERCEPTEE PAR LE COUVERT DES FORETS.
Si toute l'eau précipitée de l'atmosphére arrive sans obstacle jusqu’a un terrain
découvert, il n’en est pas de méme en forét, ot les cimes et branchages en arrétent
une fraction qui s'évapore ensuite. Dans quelle proportion le couvert empéche-t-il la
pluie de parvenir au sol? La question a de l'intérét en ce qui concerne l’alimentation
des sources, d’olt les recherches entreprises 4 ce sujet et poursuivies simultanément
aux Ging-Tranchées et 4 Bellefontaine. Les observations n’ont porté que sur des peu-
plements d’arbres a feuilles caduques (chéne, charme et hétre), mais les installations
ont été un peu différentes dans chacune des deux stations ; les résultals obtenus dans
Pune et dans l'autre seront examinés séparément.
A. —~ Station pes Cing-TRANCHEES.
Pour comparer 1a quantité d’eau recue par le sol hors bois et sous bois, il suffit de
disposer dans ces conditions deux pluviométres situés a faible distance. C'est ce qui
a été fait, aux Cing-Tranchées : le premier étant placé au milieu d'une clairiére de
quelques hectares, le second sous un perchis de hétres et charmes moyennement
serré, dgé de 4o ans au début des recherches.
Linstrument établi en terrain découvert ne présente aucune particularilé; il n’en
est pas de méme. de l'autre. La quantité d'eau pluviale qu'il regoit peut en effet varier
avec la position de l'instrument, suivant qu'elle correspond aux pleins ou aux Lroudes
du feuillage. Pour éviter cette cause d’erreur, on a donné au récepteur de fortes di- »
mensions: sa surface est égale 4 la projection de Ja cime d'un arbre du massif. la tive
de l'un d’eux le traverse en son milieu et est entourée par une collerette; grace a cette
disposition, on peut recueillir eau qui ruisselle le long du fit, soit a la suite d'une
pluie prolongée ou d'un brouillard intense, soit apres un dégel produisant Ja fusion
de la neige ou du givre fixé sur les branches.
Commencées en 1867, les observations ont été poursuivies jusqu’en 1898, un
accident arrivé 4 l'un des appareils ayant empéché de les continuer plus longtemps.
Elles embrassent donc une période de 32 ans.
Les rapports antérieurs ont fait connaitra les relevés mensuels fournis, jusqu'en
1889, par les deux plaviometres hors bois et sous bois. Quant 4 ceux ie années
suivantes , ils sont consignés dans le tableau ci-apres :
“ La vallée de la Meurthe.
(2) Les forets isolées au milieu d’une plaine se préteraient a ces observations; celle d’Orléans se recom-
manderait en particulier en raison de son importance el de sa situation.
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—+9( 21 ea—
A part quelques tres rares exceptions, pour tous les mois de l'année, Ja quantité
d'eau recueillie hors bois est plus forte que celle recue par le sol forestier. On n’a pas
constaté & Bellefontaine, comme aux Cing-Tranchées, des anomalies assez fréquentes
et importantes; la cause cn est d’abord la consistance du massif, plus dense et plus
dgé; puisda défectuositd de Vinstallation, la forme des pluviométres, leur situation ()
rendent peu précises les indications qu’ils fournissent..
Sous ces réserves, on trouvera ci-aprés les résultats d’ensemble pour toute la période
des observalions, présentés dans la méme forme que ceux des Cing-Tranchées :
) Les hauteurs relevées au pluviométre sous bois sont plus ou moins fortes suivant l’emplacement qu'il
occupe sous le massif. Divers déplacements de l’appareil en ont fourni la preuve.
—t9-( 22 )ea-—
Tasteau N. — Stariox ve Betveronraine.
QUANTITES D°EAU TOMBEES RESPECTIVEMENT HORS BOIS ET SOUS BOIS PENDANT LA SAISON CHAUDE,
LA SAISON FROIDE ET L*ANNEE ENTIERE |),
MAI A OCTOBRE.
NOVEMBRE A AVRIL.
ANNEE ENTIERE,
HORS BOIS, SOUS BOIS. HONS BOIS. SOUS BOIS. HONS BOIS. sous pols,
a i eed a i eel a
ANNEES. SPAISSEUR Spatsszon eae EPaisseUR | KPAISSEUR ae EPAISSEUR | EPAISSEUR Paes
de de pondant de de -pondant de de pondant
Ja lame lalame [A une chule] Ja lame Jalame /4 unechute} Ja lame { 1a lame [a une chute|
d'eau d'eau “de d'eau d'eau de d'eau dau de
recueillie. | recueillie. ee aye ; reeneillie, | recueillie. pear ‘| recucillie. | recueillie Tigie eo
millim. willio. tmillin. millim. millim, millim, millio. willim, millim,
1867.... 348.0] 261.0] 75.0 531.0] 414.0] 78.0 879-0] 675.0] 76.8
1868.... 323.0] 298.0] 70.6 415.01 331.0) 79.8 738.0] 559.0) 75.7
1869.... 377-0] 293.0] 77-7 844.0] 276.0] 80.2 7a1.0| 569.0] 78.9
1870.... 377.0} 347.0) 92.0 216.0 188.0] 87.0 593.0} 535.0] go.
1871.... 4og.o] 369.0] go.a 299.0] 266.0] 89.3 708.0] 635.0} 89.7
1872.... 498.1! 358.0] 83.6 4hg.7| 405.0} go.0 877.8] 763.0) 86.9
1873.... 430.4| 339.0] 78.8 310.5] 2374.6) 88.4 740.9] 613.6] 82.8
1874.... 333.5] 266.41 79.9 285.4 253.6; 88.9 618.9} 520.0] 84.0
1875.... 545.8| 4ha.A} 80.6 348.4) 314.1] go.2 Sg4.0} 756.5] 84.6
1876.... Kika} 331.4) 80.0 433.2] 396.5] 91.5 847.4] 727.9] 85.9
1877.... 434.8} 356.1) 81.9 5a7.1 466.1; 88.4 gS1.9] 822.0; 85.5
1878.... 587.9] fg2.4) 83.9 43y.5| 378.4) 86.1 1026.7] 870.8) 84.8
1879....| 517.7| 439.1) 84.4 461.5] 4o2.6) 87.2 979-2] 839.7] 858
1880.... 479.7} 395.4] 83.6 398.0} 347.8] 87.4 870.7] 743.2] 85.4 ff
1881.... hog.4 347.9| 85.0 327.4 280.7] 85.7 736.8) 618.6) 85.3
1882.... 525.2 4hg.g| 85.47 419.9 363.1] 86.9 gha.g] 813.0] 86.9
1883.... 547.4 493.9] 90.3 369.0 335.2] 90.8 916.1] 829.1] 90.5
1884.... 285.7] 302.0] 70.7 3ho.g| 291.9} 85.4 626.6] 493.9} 78.7
1885.... 471.2| 4o3.0] 85.5 843.5) 313.7] 918 814.7] 716.7) 88.0
1886.... 4g7.8 hod5.o} 81.4 393.8 341.5) 86.7 8gt.1] -7A6.4} 83.8
1887.... 433.4) 380.1) 76.2 286.8] 253.31 87.6 720.2} 582.4} 80.9
1888.... 531.5) 4a1.4| 79.3 317.7 266.4] 83.9 849.2] 687.8] 81.0
1889... 4o1.3) 321.9) 76.4 269.7 g21.5) 89.4 691.0] 543.4] 78.6
| 1890.... 434.8 318.4] 735.9 269.4 216.3) 82.4 697.2) 534.9] 76.7
1891.. 461.6} 346.2} 75.0 314.9] 268.1} 85.1 776-5] 614.3) 79.1
1892.... 552.0 456.2} 82.6 297-9 251.5] 84.5 849.9] 707.9} 83.3
1893... 4od.1 299.0] 73.9 287.4 270.4) g4.1 699.5] 569.4) §a.9
1894... 405.6} 299.1] 73.7 251.9| 239.0] 94.9 657.5] 538.1] 81.8
1895... 393.4) 289.5) 73.6 497.5) 439.7] 88.4 890.9] 729.2) 81.8
1896.... 4g7.9| 3881.6) 76.6 275.61 959.4] 91.6 773-5] 634.0] 82.0
1897.... 434.8) 350.0] 80.5 320.6) 90.7} 90.7 795.4] 640.7] 84.8
1898.... 393.3} 304.3) 77.4 286.7] 251.6) 87.8 680.0] 555.9) 81.8
1899.... 478.5 391.0] 81.9 398.9] 348.7] 87.6 876.7] 739.7| 83.4
Toraux. . | 14577.5| 11726.6 " 11717.g} 10207.8 Y 26295.4] 21934.4 a
Movennes. hha.) 355.4} 80.5 355.1 309.3! 87.4 796.8] 664.5] 83.4
“) Voir a Ja fin Je tracé graphique.
——+0( 23 ees
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—-+»( 24 )es-—
On voit qu’a Bellefontaine I'action des cimes est plus sensible qu’aux Cing-Tran-
chées; la pluie se trouve interceptée, année moyenne, dans la proportion de 16,6 p. 100
au lieu de 7,6 p. 100. Ceci tient sans doule A I'épaisseur plus grande du couvert,
mais certainement aussi au défaut de précision des observations.
Toutefois, en dépit de ces critiques, les résultats obtenus concordent avec ceux de
la premiere station. :
On remarque la méme diflérence dans |’arrosement du sol forestier suivant les sai-
sons; il regoit en hiver 87,1 p. 100 de l'eau tombée de l’atmosphere et 80,5 p. 100
seulement pendant I’été.
De méme, on constate que la fraction retenue par les branches, qui est assez faible
et 4 peu prés constante de novembre A mars, augmente Iégérement en avril, puis trés
notablement en mai. Au mois de juin a lieu une faible diminution, commencement
d'une décroissance qui, interrompue en juillet-aodt par un relevement plus ou moins
sensible, s'accentue jusqu’a la fin d’octobre.
Z Sans qu'il y ait liew d’attribuer aux recherches poursuivies_4 Bellefontaine plus.
“ Vimportance qu’elles n’en méritent, il faut pourtant reconnailre qu’elles n’ont pas
été Tnutiles; on leur doit une confirmation, qui nest pas sans valeur, des observations
faites aux Cing-Tranchées.
Reste maintenant a tirer de toutes les données qui précédent les conclusions qu’elles
comportent relativement 4 l’alimentation des sources. La question a résoudre est la
suivante : le sol abrilé par la forét est-il mieux arrosé que celui de la région agricole ?
Pour savoir & quoi s’en tenir, i] suffit de comparer les indications des pluviométres
installés sous bois aux Cing-Tranchées et a Bellefontaine avec celles de Tinstru-
ment établi 4 Amance-la-Bouzule. Le tableau qui suit donne 4 cette fin, et sépa-
rément pour l’été, Thiver ect lannée entiére, les résultats des observations pour loute
la période qu’elles embrassent.
Tasteau P.— Comparaison ENTRE LES QUANTITES D'EAU PLUVIALE PARVENANT AU SOL
DANS UNE REGION AGRICOLE D UNE PART ET, D AUTRE PART, EN FORET, A LABRI DU
massiF),
TAIT SRR ES
MAI-OCTOBRE. NOVEMBRE-AVRIL. ANNEE ENTIERE.
ee ree
ANNGES. [LES ciNO-| BELLE- | amance- | LES GING-] BELLE-| ygancg-| LES CINO- | BELLE- | ayance-
TRANCHERS| FONTAINE| 4 | TRANCHGES|FONTAINE] 1, | TRANCHSES| FONTAINE] — 54
(eee | Ge Journ. | (| 0% foocanne.) (ie | G8, | sours
millim. millim. | millim. millira, | millim. | millim. millim. millim. millim.
1867.....| 340.0 | 261.0 | 315.0 | 528.0 | 414.0] 547.0 | 868.0 | 675.0 | 862.0
1868..... 290.0 | 228.0 | 978.0 | 413.0 } 331.0| 353.0 | 703.0 | 5hg.0 | 631.0
1869..... 395.0 | 293.0 | 303.0 | 334.0 | 976.0] 325.0] 729.0 | 569.0 | 628.0
1870..... 332.0 | 347.0 | 332.0 | 910.0 | 188.0] 186.0] 5he.o | 535.0 | 518.0
1871.0 6.. 389.0 | 369.0 | 365.0 272.0 | 266.0] 260.0] 661.0 | 35.0 | 625.0
1872 seco 390.1 | 358.0 | 347.1 ho3.9 | 405.0] 369.9 | 794.0 | 763.0 | 717.0
1873..... 403.9 339.0 391.3 270.2 | 274.6] 249.7 | 674.1 | 613.6 | 639.0
1874..... 341.7 | 266.4 | 308.9 | 319.0 | 253.6] 237.0 | 660.7 | 520.0 | 545.9
1875..... 578.0 | Aha | 351.4 329.7 | 314.1 | 246.1 | 907.7 | 756.5 597-2 .
1876..... 334.6 | 331.4 | 2967.6 hae.o | 396.5) 402.3 } 756.6 | 727.9 669.9
1877..... 353.1 | 356.1 | 399.9 418.0 | 466.1 | holy | 771.1 | S222 746.9
Voir a Ja fin le tracé graphique.
—+»( 25 )es—
SS II ET ES SN
MAI-OCTOBRE. NOVEMBRE-AVRIL. ANNKEE ENTIERE.
: : ne |r
ANNGES. | EBS GINO-| BELLE- | ayancu- | LBS CINQ-| BELLE- | syance- | LES clNO-| BELLE- ) ayancE-
TRANCHEES| FONTAINE| 5, |TRANCHEES|FONTAINE] 1, |TRANCHEES| FONTAINE] 4
fois), | bos). | Bovz0me: | fetes. | feiy, |rovzone) (ois | GE | nouzune.
millim, nillim. millim, millim, | millim. | millim. millim, | millim. millim.
Ii 1878..... 481.8} 4ga.4) 497.3] 401.7] 378.4] 348.5] 883.5) 870.8) 8325.8
1879..... 473.4) 437.1) 458.8} 407.9] 402.6) 268.1 881.3} 839.7] 726.9
1880..... 453.3] 395.4) 371.8) 399.2} 347.8) 307.1 845.5, 743.2] 678.9
1881..... 321.8} 347.9) 269.8} 312.3) 280.7] 344.5] 634.1} 628.6) 514.3
4882..... 487.1] 4hg.g) 490.3} 393.6] 363.1} 332.3] 880.7) 8138.0] 822.6
1883..... 469.5] 493.9} 4a8.g]) 353.1) 335.0] a5a.0] 822.6] 829.1 680.9
1884..... 287.3} 2902.0] 301.8| 350.6] 991.2} 258.5] 637.9] 493.2} 559.7
1885..... 534.0} 403.0] 417.0] 4a2.o} 313.7} 346.0] 956.2] 716.7] 763.0
1886..... 458.5) 405.0} 411.6} 498.7) 341.4] 326.4] 887.2] 746.4) 738.0
1887..... 4e1.0o] 380.1) 324.5) 306.7] 259.3] 259.5] 727.7] 582.4] 597.0
4888..... 595.1] 4a1.4) 470.5} 403.3) 266.4) 253.1 998.4] 687.8) 723.6
1889..... 4gg.8) 321.9) 331.0] 333.0] 9291.5) 931.0] 829.8) 543.4] 582.0
1890..... 467.1] 318.4) 394.7] 360.8) 916.3) 234.5] 847.9] 534.7) 629.2
1891..... 54o.1] 346.0} 406.3) 371.8] 268.1] 265.9] gt1.9] 614.3) 6472.9
1892..... 576.0} 456.2) 440.5 389.3} 251.7] 192.6 965.3] 707.9] 635.1
1893..... ‘| 333.1] 299.0] 295.7} 340.6) 270.4] 209.7] 673.7] 569.4) 505.4
1894..... 4h7.6} 299.1] 321.4 284.9] 939.0] 911.1 732.0) 538.1 532.5
1895..... 393.5] 989.5) 319.5) 543.9) 439.7) 461.6) 937.4) 729.2] 674.1
1896..... 4a7.9| 381.6} 445.8 271.1] 259.4) 2915.7 699.0} 634.0] 661.5
1897..... 372.1] 350.0) 378.5] 998.0] 990.7] 191.8] 670.1] 640.7] 570.3
1898..... 306.0] 304.3] 309.7] 259.6) 251.6] 174.4] 565.6) 555.9) 484.1
Toraux. ..| 13493.6) 11335.6] 11661.0| 11534.9] 9859.1] 9076.0] 25028.5| 91194.7| 20737.0
‘Movennzs. . 4o1.7| 354.9) 364.4] 360.4) 308.1) 283.6] 782.1] 662.3; 648.0
L’examen des chiffres montre que le terrain de la forét de Haye, au centre du!
massif, est toujours mieux arrosé que celui des plaines voisines. La différence est sur-|
tout sensible Vhiver; elle s'atténue l’été par suite de la présence des feuilles. Année |
moyenne on ne recueille 4 Amance-la-Bouzule que 82,9 p. 100 de la quantité d’eau |,
pluviale recue sous bois aux Cing-Tranchées, 1a proportion étant de 86,4 p. 100 pour
les mois de mai a octobre et de 78,7 p. 100 seulement pour ceux de septembre a avril.
Si on fait la comparaison entre Jes relevés de 1a station agricole et ceux de Belle- |,
fontaine, on obtient respectivement, au lieu des rapports précédents, ceux de 97,8
— 102,9 — 92,5 p. 100. Ces constatations concordent avec les précédentes, tout en
étant moins nettes, ce qui est naturel, les observations ayant été faites non plus au
milieu, mais sur la lisiére de la forét.
Le terrain occupé par de grands massifs feuillus est donc mieux arrosé, en hiver
surtout, que le sol nu des régions voisines non boisées; lalimentation des nappes sou-
terraines n’est par conséquent nullement compromise, au contraire, par le couvert des
foréts. Telle est 1a conclusion qui se dégage, avec évidence, de ces recherches pour-
suivies pendant trente-trois années.
II]. — Mancne ve L’EVAPORATION HORS BOIS ET SOUS BOIS.
Une fois arrivée jusqu’au sol, l'eau pluviale ou bien s’infiltre dans ses profondeurs,
on bien retourne dans atmosphere a l'état de vapeur. Si on arrive 4 déterminer la
—+>( 26 )er~-
fraction qui s’*évapore, on connaitra par 14 méme celle qui alimente les nappes souter-
raines et les sources. De 14 les recherches entreprises a ce sujet.
L'évaporation se produit d’ailleurs de deux maniéres : soit directement, soit par
Vintermédiaire des plantes en verlu de leur transpiration.
Comment connaitre la quantité d’eau absorbée par les racines d'un massif forestier?
Le probléme est complexe et difficile, et, en dépit des travaux de von Hobnel,
Th. Hartig, Risler et autres, est encore loin d’étre résolu aujourd’hui. C'est dire
quien 1866 on ne tenla pas encore d’en aborder l'étude, et les observations com-
mencées alors aux environs de Nancy n'ont visé que l’évaporation directe ou physique.
«Réduite & ces termes, Ja question reste encore pleine de difficultés. Comment, en
effet, déterminer la quantité d’eau que perdent 4 chaque instant, hors bois et sous
bois, non pas des lots isolés de terre, mais des sols en place, tels qu’ils doivent étre
étudiés? Cependant, comme il s’agit ici bien moins de déterminer une quantité absolue
qu'une relation entre les volumes de I’eau évaporée 4 Yair libre et sous le couvert de
fa forét, il a paru que des atmidométres enfoncds dans le sol, de mémes dimensions,
exactement comparables enfin, donneraient une solution satisfaisante du probléme!.»
Deux bassins d’évaporation furent donc installés, 4 Bellefontaine, 4 cdté des pluvio-
métres destinés aux observations précédemment rapportées concernant la quantité d'eau
pluviale interceptée par le couvert des arbres. L’un se trouvait done au milieu d'un
terrain non boisé, l'autre sous un massif assez touffu de charmes, hétres et frénes, dgé
de soixante ans au début des recherches.
Ces bassins consistent en une caisse parfaitement étanche, en chéne garni de zinc,
de forme carrée, mesurant 1 m. 50 de cété et 4o centimétres de profondeur. Elle est
enfoncée dans le sol et reposé sur un massif de maconnerie.
Pendant toute la durée des observations qui ont été poursuivies de 1867 a 1899,
les atmidométres ont été remplis d'eau, le premicr de chaque mois, sur une profondeur
de 30 centimetres. Les variations qui se produisaient dans le niveau du liquide, soit
par évaporation, soit par la chute de la pluie, variations rendues sensibles par le
déplacement d’un index le long d’une échelle graduée, ont fait lobjet de mesures quoti-
diennes. Les pluviométres voisins des bassins permettaient en méme temps de con-
naltre Pépaisseur de la tame d’cau recue de l’atmosphére®),
Les relevés mensuels fournis respectivement par chacun des almidométres pendant
les deux périodes 1867-1877 et 1878-1888 ont figuré dans les précédents comptes
rendus. On exposera donc ici seulement ceux qui concernent les onze derniéres
années.
“) M. Mathieu. Rapport de 1848, page 18
® On pourrait objecter, fait remarquer M. Mathieu, que !’épaisseur de la couche d'eau évaporée varie
avec Pinstrument qu’on emploie. On ne saurait denc conclure des indications d’un atmidométre Tépais-
senr de Ja Jame qui s’évapore & Ja surface d’un volume d'eau trés considérable (lac ou élang). Mais il ne
s'agit pas ici de rechercher une valeur absolue, mais une relation entre l’évaporalion hors bois et I'éva~
poration sous bois. Pour y parvenir, il suffit que, sauf la différence qui résulte de I’état boisé ou dénudé
du sol, toutes Jes autres circonslances soient égales et notamment que les deux bassins d’évaporation
soient semblables entre eux et semblablement installés. Cette condition est complétement observée a Ja
station de Bellefontaine. (Mathieu, loc. cit.)
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Il est facile de constater que, conformément aux prévisions, l'évaporation a été beau-
coup moins intense en forét qu’en terrain découvert. Le rapport entre les quantités
d’eau perdues par chacun des bassins est d’ailleurs variable d’un mois a l'autre. Le
tableau ci-aprés permettra de se rendre bien compte de la marche différente du phé-
noméne hors bois et sous bois; il donne, en effet, d’abord pour trois périodes égales
et successives de onze années, puis pour la durée tout entire des observations, les
relevés mensuels moyens des deux atmidométres.
—+e( 29 \eea-—
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—+0( 39 )14+—
On voit que durant le semestre d’hiver, au moins pendant les mois de novembre,
mars et avril, pour lesquels on posstde des données suffisantes, le bassin établi en
terrain découvert a toujours perdu 4 peu prés deux fois autant d’eau que autre. L’abri
d'un massif dépouillé de sa. verdure a done pour effet de diminuer de moitié l’intensité
de Pévaporation.
En été, 1a différence est bien plus sensible, 4 cause de 1a présence des feuilles: elle
est d’ailleurs variable et d’autant plus forte que Ja température est plus élevée. Le
rapport entre les relevés des atmidométres hors bois et sous bois est égal 4 3 en mai,
A 5 en juin, juillet, aout, 4 4 en septembre et a 3 en octobre.
Ces variations tiennent aux différences que présente, pendant la saison chaude, la
marche de I’évaporation en plein champ et en forét.
Dans le premier cas, le phénoméne dépend surtout de la radiation solaire; la quan-
tilé d’eau qui retourne a l'atmosphére croit done rapidement jusqu'au mois le plus
chaud et diminue ensuile régulierement.
Sous le massif, au contraire, Vinfluence du couvert contraric celle de la chaleur,
aussi Vintensité de I’évaporation dépend-elle de la résultante de ces actions opposées.
Elle est plus faible en juin, oi Jes feuilles sont complétement développées, qu’en mai
ou elles sortent du bourgeon; augmente ensuite en méme temps que la température
jusqu’en juillet-aodt pour décroitre avec elle pendant Pautomne"),
Quelle conclusion tirer maintenant de ces observations relalivement au résime des
sources ? Il est malheureusement impossible d’en formuler aucune avec précision. On
a bien démontré que les terres évaporent 4 peu prés autant qu'une nappe d'eau, quand
elles sont saturées, mais ce cas est exceplionnel. L’intérét principal des recherches
réside done dans ce qu’elles altestent la résistance qu’opposent au desséchement du
, 801 les cimes feuillées des foréts. Il semble logique d’en déduire qu’elles favorisent,
‘par celle raison, Valimentation des sources; mais 1a chose n’est vraie — il imporle
de bien le remarquer — que si on considére uniquement Vinfluence des massifs boisés
sur évaporation physique, la seule dont on se soit occupé dans les observations.
CONCLUSIONS GENERALES.
Plusieurs faits intéressants se dégagent des recherches relatives a !'action des foréts
sur le régime des sources, recherches entreprises, il y a trente-trois années, par
M. Mathieu, sous-directeur de l'Ecole forestitre. Exposés pour la premiére fois par Jui-
méme, en 1878, ils ont été confirmés depuis, tant par les observations ullérieures
faites aux environs de Nancy que par celles effectuées sur d'autres points, en France
ou 4 V'étranger ; ils sont aujourd'hui bien établis el universellement reconnus. Ces faits
sont les suivants : OO a
1° La pluie est plus abondante dans une région boisée que dans une contrée agricole:
| I convient d'ailleurs de noter, comme I'a fait remarquer M. Bartet dans son rapport de 1889
(p- 14), que, si telle est la loi générale qui découle des moyennes, il s'en faut de beaucoup que Jes choses
se passent toujours ainsi dans la réalité. 11 n’y a pas d’année oit il n’y ait une ou plusieurs exceptions
dues soit aux vicissitudes du climat, soil a la précocilé plus ou moins grande de la végélation. On sait
daillenrs combien de causes influent sur Vintensilé de l'évaporation : surlace de la nappe d'eau; pression
almosphérique, agitation de l'air, etc.
—+o( 31 jea—
2° La quantité d’cau inlerceptée par les cimes des arbres A feuilles caduques est
relativement faible“, le sol des foréts feuillues est donc aussi bien arrosé, sinon plus,
que celui des champs voisins;
3° Par contre, le couvert d'un massif protége le terrain contre l'influence assé-
chante des rayons solaircs.
Il semble donc qu'il soit maintenant permis d'aflirmer que les nappes souterraines
sont mieux alimentées en pays boisé. C’est 1a conclusion finale qu’on croyait pouvoir
formuler il y a vingt ans : il sied aujourd’hui d’étre plus réservé.
On a cru en effet, jusqu’a une époque récente, qu'il n’y avait pas lieu de tenir
comple, dans I’éiude de !a question, de I’évaporation qui se produit par l'intermédiaire
des végétaux.
On admettait, en se basant sur des considéralious théoriques, que le pouvoir
exhalant des foréts élait inférieur ou tout au plus égal A celui des cultures agricoles.
Or le contraire parait prouvé par les travaux effectués depuis quelques années.
Dans ces conditions, il est actuellement impossible de se prononcer, il faut attendre
pour cela qu’on ait des données précises sur les quantités d’eau absorbées par les
arbres),
Les observations dont il vient d’étre rendu compte n’ont done pas permis de recon-
naitre exaclement quelle était Yinfluence des foréts sur le régime des sources; elles
nen ont pas moins leur importance ct leur intérét. Si un point reste douteux, plu-
sieurs résultats sont acquis, et l’honneur en revient 4 M. Mathieu : le premier, il a
abordé l'étude du probleme, et, quelle que soit la solution, on lui devra toujours la
détermination de ses premiers éléments.
“) Pour jes résineux, il résulte, d’observations failes aux environs de Senlis, qu'un massif de pins
sylvestres retient plus de fa moitié de l’eau qui lui est versée. Bien que a différence entre les quantités
de pluie tombant sur une forét et sur la région agricole voisine soit encore plus accenluée quand il s‘agit
le peuplements résineux, Je sol se trouve, en définitive, moins bien abreuvé a l'abri de ces derniers.
Observations météorologiques faites de 1874 4 1878, par M. Fautrat, sous-inspecteur des Foréts.
Imprimerie nationale, 1878.
) D’observations récentes failes en Amérique, il résulterait que les quantités totales d’eau évaporée
(directement et par Vintermédiaire des plantes) sont les mémes pour les terrains bois¢s et non boisés,
toutes choses égales d’ailleurs. Voir The state Geologist of New Jersey et Revue des Eaux et Foréts (15 f2-
vrier 1901, p. 105). Compensation faite de la plus grande Sbondance des pluies et de l’eau qui intersepte
le couvert des arbres dans les régions boisées, les nappes Sguterraines du sol seraient donc en fin de
compte pareillement alimentées quel que soit l’état superficiel. By forét, les sources auraient seulement un
débit plus régulier.
Cacrtaktous at oa tte ‘Wei
Sorel Wd
rd is
Impaimente nAtionate. — Juillet 1901.
TABLEAU R._ STATION DE BELLEFONTAINE
MARCHE DE L’ EVAPORATION HORS Bats ET SOUS BOIS
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TABLEAU K _ STATION DES CINQ-TRANCHEES
HAUTEUR DE LA LAME D’EAU MENSUELLE RECUEILLIE SOUS BOIS
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TABLEAU 0. STATION DE BELLEFONTAINE
HAUTEUR DE LA LAME D’EAU MENSUELLE RECUEILLIE SOUS BOIS
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Janvier Février Mars = Avril §= Mai_-—S Juin = Juillet. = Aoait’ Septembre Octobre Novembre Décembre
REPEUPLEMENT DES RIVIERES
EN MEURTHE-ET-MOSELLE
SYSTEMES ADOPTES. — RESULTATS OBTENUS
PAR
R. DE DROUIN DE BOUVILLE
GARDE GENERAL
ATTACHE a LA STATION D'EXPERIENCES ET RECHERCHES
DE L’ECOLE NATIONALE DES EAUX ET FORETS
EXTRAIT
BULLETIN DES SEANCES
SOCIETE DES SCIENCES DE NANCY
REUNION BIOLOGIQUE DE NANCY |
Le Repeuplement des riviéres en Meurthe-et-Moselle. Sys-
témes adoptés. Résultats obtenus, par M. Raoul pe Drouin
pE Bouviizz, garde général attaché a la Station d’expériences et
-recherches de I’Ecole nationale des Eaux et Foréts?.
Il y a une cinquantaine d’années, l’apétre de Ja pisciculture en
France, le professeur Coste, annoncait qu’une époque viendrait
ou Phomme sémerait le poisson dans Jes cours d’eau comme il
jette le blé aux sillons.
Cette prophétie s’est aujourd’hui réalisée.
Depuis plusieurs années, en effet, on s’est préoccupé sérieuse-
ment de porter reméde a la dépopulation des riviéres, de nom-
breux essais ont été tentés pour leur rendre leur richesse d’antan.
Le moment semble donc venu d’examiner les résultats obtenus
pour en tirer quelques conclusions sur la valeur des procédés em-
ployés.
Le département de Meurthe-et-Moselle est un de ceux ot les
tentatives de repeuplement ont eu le plus d’importance. L’opinion
publique n’y est pas restée indifférente 4 la diminution constante
du poisson, a la disparition presque complete de l’écrevisse. Aussi
1, Communication faite a la Société des sciences le 17 mai 1991.
—_— 2—
des subventions furent-elles accordées sans difficultés par le Con-
seil général 4 l’administration des ponts et chaussées d’abord, et
ensuite 4 celle des eaux et foréts, pour la remise en valeur des
cours d'eau.
De leur cété, les pécheurs 4 la ligne, réunis en sociétés, ont
procédé avec persévérance a l’empoissonnement des lots de péche
dont ils étaient adjudicataires.
Les particuliers et les agents de l’Etat rivalisant ainsi de zéle
pour l’aquiculture, des efforts sérieux ont été faits dont il paraitra
sans doute intéressant de donner un compte rendu rapide, en fai-
sant connaitre les succés qu’ils ont eus. Ce sera I’objet de Ja pré-
sente communication.
Les renseignements nécessaires ont été pris 4 bonne source : la
plupart ont été fournis par une enquéte que M. Lamblé, conser-
vateur des eaux et foréts, et M. Thoux, ingénieur en chef des
ponts et chaussées, ont bien voulu, avec la plus grande amabilité,
faire entreprendre par le personnel chargé de la surveillance dela
péche. D’autres sont dus aux présidents des sociétés de pécheurs
a la ligne, et notamment 4 MM. Florentin (de Toul), Rousselot
(de Lunéville) et Chatton (de Baccarat).
Les méthodes de repeuplement étant trés différentes suivant
les espéces dont on a en vue la propagation, nous passerons suc-
cessivement en revue les tentatives faites en ce qui concerne : les
poissons migrateurs, la truite, les poissons d’été et l’écrevisse.
Poissons migrateurs.
Le saumon remontait autrefois la Moselle et venait frayer dans
les petits ruisseaux des Vosges ; il y a une vingtaine d’années, il
était devenu trés rare; on ne le rencontre plus aujourd’hui que
tout 4 fait exceptionnellement.
Les échelles 4 poissons ne font cependant pas défaut; depuis
une vingtaine d’années, tous les barrages de quelque importance
en sont munis, méme ceux des sections canalisées, qui n’en com-
portent pourtant pas. Ces derniers sont en effet des barrages mo-
biles dont les fermettes sont d’ordinaire couchées, ou tout au
moins désaiguillées en partie, 4 ’époque des hautes eaux qui est
celle de la remonte.
Aucun résultat n’a été remarqué, bien qu’il n’y ait plus, depuis
longtemps, aucun obstacle a la circulation des poissons migrateurs.
nn
L’insuccés s’explique toutefvis si on admet que le saumon re-
tourne frayer aux lieux mémes oi il est né. Il conviendrait donc,
pour que cette espéce fréquentat de nouveau les eaux lorraines,
de faire des déversements d’alevins a la partie supérieure des
riviéres. Ces sujets y reviendront déposer leurs ceufs, si tant est
qu’en effectuant leurs migrations, ils échappent aux engins des-
tructeurs de pécheurs de nationalités différentes, peu enckins a
laisser un poisson aller se faire prendre chez le peuple voisin.
Avant d’en finir avec le saumon, signalons un essai d’acclima-
tation du saumon de Californie dans la Meurthe, qui a eu lieu, il
y a quelques années, sans aucun succés d’ailleurs..
L’alose et la lamproie sont inconnues en Lorraine, il ne reste
donc plus, en ce qui concerne les poissons migrateurs, qu’a parler
de l’anguille.
Cette espéce parait moyennement répandue dans les cours
d’eau et, vu sa voracité, on pouvait se demander s’il y avait inté-
rét a la propager. L’administration des ponts et chaussées l’a
pensé et depuis 1895 a fait déverser dans la Moselle, auprés de
Toul, environ 145,000 petites anguilles recueillies 4 ’'embou-
chure de la Somme. Le résultat obtenu a été satisfaisant et il est
juste de reconnaitre que ces anguilles ne paraissent pas avoir
prospéré au détriment des autres espéces.
Truite.
La truite ne se rencontre guére, en Meurthe-et-Moselle, que
dans la partie nord du département et dans les ruisseaux de la
chaine séparant la vallée de la Vezouse de celle de la Plaine.
Sa diminution dans ces cours d’eau, son absence dans d’autres
ou elle semblerait devoir se plaire, excitaient des plaintes et re-
grets chez les pécheurs. Notons en passant que ceux-ci étaient
souvent responsables de la situation. Sur nombre de points en
effet, on signale comme cause de ta diminution de la truite et
aussi de la perche et du brochet, la péche a la ligne a Vaide de
cuillers ou poissons d’étain, et surtout en employant comme
amorce la larve de Péphémére (dite « petite héte ») dent les espé-
ces voraces sont extraordinairement friandes.
Quelle que fit la raison de la dépopulation, on s’inquiéta d’y
porter reméde dés que le Conseil général eut décidé de consacrer
sei
annuellement une certaine somme au repeuplement des cours
d’eau, c’est-a-dire A partir de 1894. Jusque-la quelques déverse-
ments d’alevins avaient bien été effectués par certains particuliers,
mais sans résultat senstble.
Une difficulté se présente toutes les fois qu’il s’agit d’introduire
la truite dans un cours d’eau. Si les sujets employés sont trop
jeunes, ils sont délicats, incapables de trouver leur nourriture et
de fuir leurs ennemis; s’ils sont dgés d’un an, le prix auquel les
livrent les établissements de pisciculture rend le repeuplement
trés cofiteux.
Pour obtenir ces derniers au meilleur compte possible, le sys-
téme adopté en 1894 par le service hydraulique, et suivi depuis
par celui des eaux et foréts, a consisté 4 essayer l’élevage d’ale-
vins dans de petits bassins établis 4 peu de frais sur des ruisseaux
& eau vive et froide. Il suffit, pour avoir une installation con-
venable, de régulariser le lit sur une certaine longueur, et de
placer en travers du courant, 4 chaque extrémité, des chassis avec
griltage. Lorsque les truitelles ont la taille voulue, on cesse de les
tenir prisonniéres, elles descendent au fil de ’eau et ’'empoisson-
nement a lieu dans d’excellentes conditions.
Quatre réservoirs de 50 4 100 métres carrés de surface ont été
ainsi aménagés dans Ie département: Je premier par l’adminis-
tration des ponts et chaussées, au moulin de la Caulre, prés Briey;
les trois autres par celle des eaux et foréts. Ces derniers sont
situés respectivement: prés de Longuyon, sur le ruisseau de la
Machine ; aux environs de Baccarat, sur celui de la Forge Evrard ;
enfin 4 la Boudouze, dans le voisinage de Cirey.
Depuis plusieurs années un certain nombre d’alevins de 1 4
3 mois, soit de truite des ruisseaux, soit de truite arc-en-ciel,
fournis par les établissements de pisciculture de la région (Her-
serange, prés Longwy ; Wasperviller, prés Sarrebourg), ont été
élevés dans ces réservoirs.
Le résultat n’a malheureusement pas répondu aux espérances.
Presque toujours la mortalité a été trés considérable '.
L’insuccés, si c’en est un, n’est d’ailleurs que relatif. Dans les
établissements de pisciculture ou on opére sur une grande échelle,
3. On n’a guere obtenu de résullats satisfaisants qu’a Longuyon, et encore une seule
année. L’eau du ruisseau de la Machine ayant été capteée, il a falluen 1899 abandonner
Vinstallation.
rn
eee FS ee
les bassins sont parfaitement entretenus et constamment sur-
veillés, les alevins recoivent tous les soins voulus, cependant le
déchet dans la production des sujets d’un an est trés considérable,
de la leur prix ', Il semble bien difficile que des élevages restreints,
faits dans des conditions moins favorables, puissent donner des
résultats meilleurs et plus économiques.
Les sujets obtenus ont donc été peu nombreux, et les empois-
sonnements ont eu par suite trop peu d’importance pour étre
d’une efficacité trés grande.
Il a été possible cependant de faire quelques remarques en ce
qui concerne la truite are-en-ciel.
Cette espéce ne parait pas se plaire dans les eaux probablement
trop froides des ruisseaux de la partie sud-est du département.
Par contre, autant qu’il a été possible d’en juger, elle a passable-
ment réussi dans les cours d’eau de |’arrondissement de Briey,
mais sa voracité est telle, et elle mord si bien’é Phamegon, que la
plupart des individus mis a l’eau ont été capturés presque aussitét
par les pécheurs.
Les essais de repeuplement dont il vient d’étre rendu compte
n’ont pas été les seuls, d’autres ont été effectués par les soins de
Yadministration des ponts et chaussées, chargée encore aujour-
d’bui du service de la péche sur la Moselle canalisée. Elle posséde
depuis 1895, a Valcourt, un petit laboratoire de pisciculture.
Celui-ci, d’abord trés modeste et alimenté par une faible source,
a été transféré en 1899 4 ’usine hydraulique qui sert 4 |’alimen-
tation du canal de la Marne au Rhin. L’établissement a continué
d’ailleurs a étre des plus simples: quelques auges en bois, une
vingtaine de bacs a éclosion, constituent tout le matériel. Cette
installation sommaire et peu coteuse a cependant suffi, depuis
qu’elle existe, pour réussir dans des conditions extrémement sa-
tisfaisantes I’élevage d’environ 100,000 alevins.
Les sujets obtenus ont été pour la plupart déversés dans la
Moselle aux environs de Toul. Dans les cing derniéres années, on
y a déposé a peu prés 40,000 truites arc-en-ciel de 3 46 mois,
25,000 truites des lacs de 3 4 g mois, 14,000 truites des ruisseaux
1. Le propziétaire de I’établissement de pisciculture de Wasperviller estime que sur
1,000 truites d’un mois mises dans les bassins d’élevage, il n’en retrouve guere que
150 au bout d’une année.
*
a: hs
de 3 mois et enfin 14,000 truites saumonées dgées d’un mois
et demi.
On n’a pas remarqué, jusqu’ici, que ces empoissonnements
aient produit grand effet: cependant les pécheurs ont certaine-
ment repris quelques-uns des individus éclos 4 Valcourt, mais
combien peu relativement au nombre de ceux qui ont été mis
& Peau.
En résumé, it faut reeonnaitre que, malgré importance des ten-
tatives, malgré le dévouement et le soin de ceux qui y ont pré-
sidé, on n’est pas encore arrivé aujourd’hui 4 un succes définitif
et durable‘. La réussite viendra-t-elle avec le temps? La chose
est possible et souhaitable... Conviendrait-il de procéder autre-
ment qu’on ne Fa fait jusqu’ici? Peut-étre... En particulier, et
quoi qu’on en ait dit, n’obtiendrait-on pas de bons résultats avee
de tout jeunes alevins, méme encore pourvus de leur vésicule
ombilicale? Vu leur prix peu élevé, il serait possible de procéder
a des déversements abondants et répétés ; on arriverait probable-
ment ainsi, malgré Je déchet trés grand sur lequel il faut compter,
a assurer le repeuplement. I] semble enfin que ces sujets, habitués
de bonne heure aux eatx ot ils doivent vivre, s’y acclimateront
mieux que s’ils y avaient été introduits 4 un Age plus avaneé.
Quoi qu'il en soit, ce qui importe, c’est de ne pas se décourager,
et tant que le procédé de repeuplement efficace ne sera pas trouvé
de le chercher par tous les moyens. La présence actuelle de la
truite sur nombre de points, les renseignements qu’on posséde
sur son abondance autrefois, sont la pour prouver que le pro-
bléme est susceptible de solution.
Poissons ad’ été.
Les poissons d’été, carpes, tanches, gardons, etc., sont ceux
qui offrent le plus d’intérét pour les pécheurs a la ligne. Aussi
depuis que ces derniers, réunis en sociétés, exploitent certains
lots de péche sur les cours d’eau du domaine public, la question
de la propagation de ces espéces a pris la téte de l’ordre du jour.
1. Il convient cependant de signaler deux ruisseaux, celui de Chatillon, prés Cirey,
et celui de Champigneulles, pres Nancy, ot la truite existe aujourd’hui en assez grande
quantité, grace aux déversements d’alevins effectués respectivement par deux proprié-
taires particuliers, M. le baron de Klopstein et M. Hinzelin. Il est vrai de dire que les
conditions ott ils les ont entrepris étaient particuligrement favorables.
~_— 7 Seo
Ce n’est pas que rien n’edt été fait auparavant. Quelques parti-
culiers avaient effectué des déversements de carpillons ou de
jeunes tanches dans les riviéres, mais ces tentatives isolées, d’ail-
leurs de peu d’importance et discontinues, ne pouvaient avoir, et
n’ont eu aucun résultat. De son cété le service hydraulique du
département s’était préoccupé des mesures 4 prendre pour remé-
dier 4 la diminution croissante du poisson d’été. En 1894, un
étang d’alevinage fut aménagé prés du bassin de Parroy; mais
les conditions n’étaient pas favorables, on dut l’abandonner peu
aprés.
Aucun effort sérieux ou utile en vue du repeuplement n’avait
donc eu lieu antérieurement 4 1896. C’est 4 partir de ce moment
qu’intervinrent les sociétés de pécheurs 4 la ligne, devenues adju-
dicataires de certaines parties du cours de la Moselle, de la Meur-
the et de la Vezouse.
Ces sociétés sont au nombre de quatre. La plus ancienne est
celle de Nancy qui existe depuis 1892; trois autres furent fondées
4 Baccarat, Lunéville et Toul en 1895-1896.
Elles procédérent immédiatement al’empoissonnement de leurs
lots, effectué au début a l’aide de jeunes carpes, tanches et per-
ches achetées lors de la péche des étangs de la région’.
Les résultats furent suffisamment satisfaisants pour étre encou-
ragés par l’Etat au moyen d’une subvention, et par le départe-
ment qui, depuis 1898, a loué un étanq uniquement destiné a la
production de sujets de repeuplement.
Cet étang, d’une contenance de 5 hectares, est situé 4 La Ga-
renne, prés Haudonville. Sa gestion est confiée au service des
eaux et foréts.
Les résultats ont été trés satisfaisants, puisqu’on y a péché en
novembre 1899, 40,000 alevins de carpe, carassin, tanche et per-
che, pesant ensemble 1,075 kilogr. et année suivante 24,600 su-
jets, mais plus forts que les premiers, puisque leur poids total
était de 1,230 kilogr.
Pendant ce temps les sociétés de pécheurs, dort les adhérents
et les ressources s’accroissaient, ne restaient pas inactives. Celle
de Lunéville louait 4 Einville un bassin pour l’élevage du gardon,
1. Bossupré, La Garenne, La Reine, Brin, Spincourt (Meuse), Gondrexange (Lor-
raine annexée), elc.
== 8
celle de Toul aménageait deux carpiéres 4 Valcourt et Pierre-la-
Treiche, enfin celle de Nancy se rendait locataire, 4 Spincourt
dans la Meuse, d’un étang de ro hectares pour y produire, dans
les mémes conditions qu’a La Garenne, des alevins de poissons
d’été.
Il a été fait par suite depuis cing ans de trés importants déver-
sements dans les principales riviéres du département, savoir :
Dans la Mosellet . . 151,000 carpes, barbeaux et tanches.
Dans la Meurthe2. . 83,000 carpes, carassins, tanches et gardons.
Dans la Vezouse3 . 28,000 _ —
Dans la Mortagne+. . 16,000 _ _
Dans le Madon‘+. . . 3,500 —_ _
Dans Je Sanon+. . . 4,000 — —
Dans ’Euron4. . . 2,500 _ —
Dans la Verdurette4. 5,000 — —
Dans le Rupt-de-Mad4 — 2,000 — —
Total. oi 295,000 2
Tous les renseignements regus sur ces repeuplements signalent
unanimement leur parfaite réussite. Cependant sur la Vezouse et
dans la Meurthe aux environs de Baccarat, les résultats n’ont pas
été complétement satisfaisants. La cause en est attribuée a l’im-
pureté de l’eau, souillée par des résidus d’usines, 4 la présence
de loutres et enfin au braconnage.
A cette exception prés, on remarque aujourd’hui, sur tous les
points ot ont été faits des déversements, une augmentation no-
table du poisson. Les carpes et les carassins, espéces rares ou
1. Les déversements ont été effectués par les soins de |’administration des ponts et
chaussées, les frais étant partagés entre l’Etat, la Société des pécheurs & la ligne de
Toul et quelques adjudicataires.
Sur les 151,000 sujets 4 l’eau, 50,000 proviennent des carpiéres de Valcourt et
Pierre-la-Treiche établies en 1899. Les barbeaux (15,000) ont été obtenus par féconda-
tion artificielle. Get essai, tenté et réussi par M. Doudoux, conducteur subdivisionnaire
des ponts et chaussées, n’a pu étre renouvelé depuis, par suite de difficultés ayant
empéché la capture des reproducteurs.
a. Une notable partie des alevins (26,000) vient de l’étang de La Garenn ; le réser-
voir d’Einville a fourni 4,000 gardons.
Les déversements ont été faits, moitié par les Scciétés de pécheurs A la ligne de
Baccarat, Lunéville et Nancy, moitié par l’administration des eaux et foréts.
3. Les tentatives de repeuplement de la Vezouse sont ducs au service forestier, aux
pécheurs de Lunéyville el & quelques adjudicataires. Les carpes, carassins ct tanches
proviennent en majorité de I’étang de La Garenne, ct 2,000 gardons du rése: voir
d’Einville.
4. Déversements effectués par l’administration des eaux et foréts, au moyen de suiets
obtenus & I’étang de La Garenne,
3
inconnues autrefois dans les eaux lorraines ‘, s’y sont parfaitement
acclimatés ; on en prend aujourd’hui de nombreux sujets de belles
dimensions. Le gardon a prospéré également, et il y a tout lieu
de penser qu’il en est de méme pour la tanche, bien qu’on soit
moins fixé a ce sujet.
Il est 4 remarquer que les empoissonnements ont eu surtout
un effet local, c’est aux endroits mémes ou ils ont eu lieu qu’on
constate une amélioration remarquable. Leur effet se fait géné-
ralement encore quelque peu sentir en aval, pas du tout en amont.
lly a la de quoi encourager pécheurs et adjudicataires, puisque
c’est 4 celui qui a semé que revient la récolte.
I] faut enfin noter que les espéces les plus employées pour le
repeuplement, a savoir la carpe et le carassin, ne se reproduisent
pas, ou du moins trés peu, dans les eaux trop froides des riviéres
de Meurthe-et-Moselle.
Il faut par suite répéter tous les ans, ou tout au moins fré-
quemment les déversements d’alevins de ces espéces. Les eaux
courantes comportent, en ce qui les concerne, une culture tout a
fait analogue 4 celle des étangs.
La propagation des poissons d’été peut donc se faire d’une ma-
niére efficace et pratique. La méthode n’est d’ailleurs pas récente,
mais il a fallu pour sa mise en pratique l’intervention des pécheurs
qui trop longtemps sont restés indifférents ou ont tout attendu
des pouvoirs publics. L’honneur des succés obtenus leur revient,
mais il revient aussi surtout a ceux qui leur ont fait comprendre
Yimportance qu’aurait une initiative de leur part, et la nécessité
de s’unir pour aboutir. C’est en particulier 4 M. Bichat, doyen de
la Faculté des sciences de Nancy et. conseiller général, qu’on
doit étre reconnaissant de ce qui a été fait pour le repeuplement
des cours d’eau en Meurthe-et-Moselle. Il y a longtemps -que
M. Bichat s’est dévoué a celte cause, et il a tout lieu d’étre au-
jourd’hui satisfait du résultat de ses persévérants efforts.
Ecrevisses.
La disparition de l’écrevisse en Lorraine est due a l’épidémie
qui, il y a une vingtaine d’années, a sévi sur la plus grande partie
de la France. Elle se déclara dans la région en 1876, et dés l’au-
1. La carpe a cependant toujours. été commune dans le Madon.
tomne 1878 tous les cours d’eau, 4 quelques rares exceptions
prés, étaient complétement dépeuplés.
Les écrevisses étaient auparavant non seulement abondantes,
mais de qualité renommée. Aussi, quand on fut certain que l’ex~
termination avait été radicale, et dés qu’on put espérer que la
maladie avait cessé, on se préoccupa de faire des repeuplements.
L’Etat y contribua tout d’abord, puis les frais furent uniquement
supportés par le département.
Les premiéres tentatives remontent 4 1880-1881, d’autres
eurent lieu en 1887; enfin depuis 1892 des déversements ont eu
lieu tous les ans, et ont été surtout importants a dater de 1898.
Au total, il a été déposé depuis vingt ans, dans les cours d’eau
de Meurthe-et-Moselle 75,000 écrevisses, dont 30,000 dans les
riviéres navigables et flottables et 45,000 dans les autres.
On a toujours employé des sujets adultes, de l’espéce a pattes
rouges, ayant de 3 a 5 ans et de ro a 15 centimétres de longueur.
Le nombre des femelles a généralement été double de celui des
males.
Toutes ces écrevisses, ou peu s’en faut, ont été achetées au
commerce, et proviennent de Ja Pologne et de la Silésie. On a
essayé, a plusieurs reprises, de se servir de celles de la région,
mieux susceptibles, ce semble, de bien s’acclimater. Mais les pé-
ches faites dans les rares cours d’eau ot la maladie n’a pas exercé
ses ravages n’ont pas été fructueuses et on a dd y renoncer.
Les déversements ont été effectués avec le plus grand soin, sur
des fagots d’épines, dans les endroits ou se trouvent de grosses
pierres, des racines, et, lorsque cela a été possible, sur les fonds
calcaires et dans les parties réservées pour la reproduction. Les
époques choisies ont été soit le printemps, soit |’automne.
Quels sont actuellement les résultats obtenus ?
Dans la Moselle. et dans la Meurthe, la réussite a été nulle;
tout au plus a-t-on pu constater, par la reprise de quelques trés
rares sujets, que I’épidémie avait pris fin. On a cessé d’ailleurs
depuis 1887, de travailler au repeuplement des riviéres naviga-
bles ou flottables, pour ne plus tenter que celui des petits cours
d’eau, ou il y avait tout lieu d’espérer un meilleur succés.
Celui-ci est malheureusement encore loin de répondre aux
espérances. Sur certains points les écrevisses sont mortes en grand
nombre, l’échec est avéré et sa cause connue :) fournilure défec-
— If —
tueuse, époque du déversement coincidant avec celle de la mue.
Dans la plupart des cas, les sujets introduits ‘paraissent avoir ré-
sisté, mais leur acclimatation n’a pas été compléte, puisque jus-
qu’ici ils ne se sont pas reproduits.
On a observé la présence de petites écrevisses, provenant cer-
tainement de celles qui ont été déversées, dans trois riviéres seu-
lement: la Verdurette, le Sanon et le Rupt-de-Mad. On ne peut
d’ailleurs discerner les causes de ce résultat relativement satis-
faisant ou plutdt celles de l’insuccés éprouvé sur les autres cours
d’eau.
L’insuccés des repeuplements récents est-il d’ailleurs absolu ?
Il serait prématuré de l’affirmer, car vu la lenteur du développe-
ment des crustacés, on ne pourra étre fixé définitivement a ce
sujet que dans quelques années. Une chose malheureusement
sire, c’est que les déversements antérieurs 4 1897, déversements
effectués dans les mémes conditions que ceux qui ont eu lieu de-
puis, n’ont amené aucun résultat.
Il convient cependant de continuer les tentatives. D’abord les
constatations faites dans la Verdurette, le Sanon et le Rupt-de-
Mad sont encourageantes, puis il parait certain qu’il n’y a pas A
compter sur la propagation naturelle de l’écrevisse. Depuis vingt
ans sa péche est interdite en Meurthe-et-Moselle ; or, si elle s’est
maintenue dans les cours d’eau ot l’épidémie n’a pas sévi, elle ne
s’y est pas multipliée comme on aurait pu le croire, et en tous cas
ne s'est pas répandue hors des limites ou elle s’est trouvée can-
tonnée en 1878.
Il importe donc d’intervenir et, faute d’autre procédé, de con-
tinuer les déversements annuels entrepris dans les derniéres années
jusqu’a ce qu’on puisse, mieux qu’aujourd’hui, se prononcer défi-
nitivement sur leur utilité.
Conclusions.
Les conclusions qui se dégagent du compte rendu qui précéde
ne paraissent pas trés encourageantes. Une seule tentative de
repeuplement a réussi, celle qui concerne les poissons d’été,
encore a-t-elle porté surtout sur la carpe, qui ne se reproduit
guére dans les cours d’eau lorrains. L’empoissonnement, 1a ot il
est actuellement satisfaisant, est donc loin d’étre assuré de fagon
a se maintenir naturellement.
—12—
On ne doit cependant pas se laisser rebuter. L’aquiculture est
a ses débuts, et qui dit débuts dit période d’essais souvent infruc-
tueux. Les efforts trés importants qui ont été faits ont prouvé une
sérieuse préoccupation de remédier a la dépopulation des riviéres ;
ils n’ont pas été inutiles, puisqu’on leur doit d’étre fixé sur la va-
leur de certains procédés. D’autres vont étre essayés maintenant,
et dans de meilleures conditions, car la question n’intéresse plus
seulement aujourd’hui les pécheurs, mais aussi les hommes de
science. Nul doute qu’avec leur concours on n’arrive au succés,
puisque aux tatonnements empiriques succédera l’emploi de mé-
thodes rationnelles, basées sur la connaissance de jour en jour
plus parfaite du monde mystérieux des eaux.
Nancy, imprimerie Berger-Levrault et Cie,
L’EXPLOITATION
ET LA
CULTURE DES EAUX DOUCES
A L’EXPOSITION INTERNATIONALE DE PECHE
ET PISCICULTURE
DE SAINT-PETERSBOURG
PAR
R. de DROUIN de BOUVILLE
Garde Général attaché a la Station d’Expériences et Recherches
de’)’Ecole Nationale des Eaux et Foréts
L’EXPLOITATION
Er LA
CULTURE DES EAUX DOUCES
A L’EXPOSITION INTERNATIONALE DE PECHE
ET PISCICULTURE
DE SAINT-PETERSBOURG
PAR
R. de DROUIN de BOUVILLE
Garde Général attaché 4 Ja Station d’Expériences et Recherches
de I’Ecole Nationale des Eaux et Foréts
L’EXPLOITATION ET LA CULTURE DES EAUX DOUCES
AL’ EXPOSITION INTERNATIONALE DE PECHE ET PISCICULTUBE
DE SAINT=PETERSBOURG
L’Exposition Internationale de Péche et de Pisciculture, organisée &
Saint-Pétersbourg, en février-mars 1902, sous le haut patronage de Son
Altesse Impériale le Grand-Duc Serge Alexandrovitch, a trouvé un
_cadre superbe dans le vaste manége Michel. Ce manége, situé dans la
‘partie centrale de la ville, non loin de la perspective Newski, qui en est
Ja principale artére, est un bdtiment de dimensions imposantes n’abri-
tant, outre quelques vestiaires et tribunes, qu’une salle unique, rec-
tangulaire, de 170 métres de longueur sur 4o de largeur. L’emplace-
ment est donc des mieux approprié aux exhibitionsdetout genre, aussile
manége Michel est-il, 4 Saint-Pétersbourg, ce qu’était 4 Paris l’ancien
Palais de l’Industrie.
Un restaurant ayant été aménagé a l’une des extrémités de ce vaste
hall, ’Exposition proprement dite n’y occupait, a lintérieur, qu'une
surface de 5800 métres carrés, mais s’étendait aussi au dehors dans la
cour précédant l’entrée. Au total,sa superticieétait d’environ 10000 métres
carrés, on peut juger déja par 1a de son importance.
La division générale était simple. Au milieu dela grande salle avait
été réservé un espace libre d’une quinzaine de métres avec bassin cen-
tral circulaire ; 4 droite et 4 gauche, trois allées paralléles divisaient le
terrain en bandes rectangulaires longues de 50 4 60 métres, larges de
6 a 8, constituant l’emplacement réservé aux exposants. Les sections
étrangéres occupaient les parties voisines du centre. A l’extérieur, étaient
installés, de chaque cété du passage conduisant au manége, les bateaux,
tentes et appareils de sauvetage.
La décoration avait été |’objet d’une attention particuliére. Au dehors
se dressaient des mats garnis d’étendards et trophées, reliés par des guir-
landes de branches vertes. Dans le manége avaient été établies a
chaque extrémité deux murailles de rochers, avec plantes, animaux, etc.,
dissimulant d’une part Jes aquariums, de l'autre l’entrée du restaurant.
"Aux murs des écussons et des faisceaux de drapeaux. Dans les diffé-
rentes sections, beaucoup de variété dans l’agencement et la disposition
des produits exposés, et aussi dans l’ornementation, ce qui n’était pour-
—,4—
tant pas sans présenter de difficulté, les motifs décoratifs éetant presque
tousempruntés aux engins ou aux produits de péche. Un superbe éclai-
rage électrique du, ici 4 des foyers puissants, la 4 des lampes Edison
multicolores, ne laissait aucun point dans l’ombre. Bref, l’aspect était
gai, agréable, pittoresque et en un mot trés réussi.
L’Exposition concernait ala fois la péche maritime et la péche flu-
viale qui occupaient chacune, dans l'ensemble, une place 4 peu prés
égale. La seconde seule nous intéresse ici, et nous examinerons succes-
sivement les parties des différentes sections qui lui ont été consacrése.
RuSSIE
L’immense surface de |’Empire de Russie est arrosée par de grands
fleuves et de nombreuses riviéres, les lacs sont abondants, surtout dans
la partie septentrionale, et les étangs nombreux en Courlande et en
Pologne. Aussi la section russe présentait-elle 4 la fois, en ce qui con-
cerne les eaux douces, beaucoup d’importance et d’intérét. Pour passer
en revue les plus notables des objets et travaux exposés, nous les ran-
gerons sous les différents chefs suivants : Poissons —- Engins de ptche
—- Produits de Ja péche — Pisciculture artificielle — Etangs — Re-
cherches scientifiques.
Poissons. — Les eaux douces de la Russie contiennent une centaine
d’espéces différentes de poissons, dont les principales sont -énumérées
ci-aprés.
Esturgeon ordinaire. Acipenser sturio (L).
" — sterlet. — ruthenus(L).
_— huso. _— huso (L).
— étoilé, — stellatus (Pall),
— russe. _ Gildenstadtii (Br),
— schypa, — schypa (Lov).
Perche ordinaire. Perca fluviatilis (L).
Sandre ordinaire.
— duVolga,
Lote commune.
Pleuronecte chagriné.
Carpe commune.
Carassin commun,
Barbeau commun.
— A téte courte,
— deGrimée,
Tanche commune.
Bréme commune.
Lucioperca sandra.
— _ volgensis (Pall).
Lota vulgaris (Cuv),
Pleuronectes cicatricosus (Pall)
Cyprinus carpio (L).
Carassius vulgaris (Nilss).
Barbus fluviatilis (Flemm).
— __ brachycephalus (Kessl).
— tauricus (Kessel).
Tinca vulgaris (Cuv).
Abramis brama (L).
Bréme singa.
— saupe.
— wimba.
— deLeuckart.
— bordeliére.
Rotengle ordinaire.
Gardon commun.
_— de Fries.
Ide jesse.
Chevaine meunier.
—_— vandoise.
—_ de Danilewski.
Chondrostome nase.
Silure commun,
Hareng de la Mer Moire.
— délicat.
Brochet commun.
Ombre de Kramer.
Saumon commun.
— heusch.
-— deriviére.
— de la Caspienne.
Truite ordinaire.
Omble chevalier.
Eperlan commun.
Ombre commune.
Sténode nelma,
Corégone blanchatre.
— de Merck.
— omoul.
— tougoun.
— peled.
— mouksoun
— lavaret.
— polkour,
— nase.
Anguille commune.
Lamproie de riviére,
— de Wagner.
Abromis ballerus (L).
—_ sapa (Pall).
— wimba (L).
— Leuckartii (Heck) .
— bjérkna (Art),
Scardinius erythrophtalmus (L),
Lenciscus rutilus (L).
— Friesii (Nordm),
Idus malenotus (Heck).
Squalius cephalus (L).
— leuciscus (Heck).
— Danilewskii (Kessl).
Chondrostoma nasus (L).
Silmus glanis (L). :
Clupea pontica (Eichw).
— delicatula (Fordm),
Esox lucius (L)..
Umbra Krameri (Mull).
Salmo salar (L).
— _ hucho (L).
— fluviatilis (L).
— caspius (Kessl).
Trutta fario (L).
Salvelinus umbla (Mor).
Osmerus eperlanus (L).
Thymallus vulgaris (Nilss),
Stenodus nelma (Pall).
Coregonus albula (L).
— Merckii (Ginth).
— omul (Pall).
= tugun (Pall).
= pelet (Lep).
— muksun (Pall).
— _lavaretus (L).
_ polcur (Pall).
_— nasus (Pall).
Anguilla fluviatilis (Heck).
Petromyzon fluviatilis (L).
— Wagneri (Kessl).
La plupart des poissons dont les noms viennent d’étre indiqués fi-
guraient a l’Exposition, soit a l’état vivant, soit conservés de différentes
maniéres.
La truite, la carpe, la tanche, la bréme, le sterlet sont 4 peu prés
les seules espéces qui fussent présentées en vie dans des aquariums (1).
(1} Il y avait en outre une belle collection de poissons d’agrément, tels que
Si.
Ces aquariums étaient artistement aménagés dans une sorte de grotte
artificielle, alimentés d’une eau trés claire et bien éclairés a l'aide de
lampes électriques. Mais, en dépit des soins pris,les sujets qui y étaient
ronfermés, peut-¢tre en trop grand nombre, souffraient visiblement de
leur captivité; beaucoup étaient blessés ou envahis par la mousse. Ces
-inconvénients sont d’ailleurs inévitables dans une installation provisoire
comme celle d’une exposition, et tous ceux qui s’occupent d’aquariums
savent quelles difficultés on éprouve, dans les meilleures conditions, a
y acclimater et a y élever des poissons.
Une installation curieuse était celle du bassin central, piéce d’eau
circulaire de ro métres de diamétre, ornée d’un groupe en son milieu,
et divisée par des grillages en cing secteurs. Dans les compartiments
ainsi déterminés étaient renfermés séparément des spécimens des diffé-
rents poissons alimentant le marché de Saint-Pétersbourg. Pour permet-
tre de les bien voir, des guirlandes dé lampes Edison multicolores étaient
disposées 4 fleur d’eau. L’effet était des plus agréables.
Les collections de poissons soit empaillés, soit conservés dans des
liquides antiseptiques étaient
A * assez nombreuses, mais sans
présenter d’autre intérét que
celui de piéces d’étude scien-
tifique; l’ceil du profane ne
sy arrétait pas volontiers.
Une seule faisait exception,
celle du Comité pour |’assis-
tance des Pomors du nord de la Russie. Chaque sujet est contenu dans
un bac en verre ayant Ja forme d’un petit aquarium et contenant du
formol. Le poisson, fixé sur une plaque de verre inclinée 4 45°, a lat-
titude naturelle de la nage et parait absolument suspendu dans son
élément. Ce dispositif satisfait & la fois, ce semble, aux exigences du
savant qui peut, en retirant la plaque intérieure, étudier 4 son aise le
poisson sans risquer de le détériorer, et au gotit du public assez réfrac-
taire aux exhibitions de piéces ressemblant a des préparations anatomi-
ques (1).
télescopes, macropodes, combattants... mais sans intérétau point de vue de l’ex-
ploitation des eaux douces dont il est ici question. ‘
(1) Outre les poissons, les eaux de la Russie fournissent encore des écrevisses,
malheureusement décimédes depuis une dizaine d’années par une épidémie dont
les ravages se sont accentuds tout récemment.
On pourrait voir a l’Exposition, & cdté de superbes spécimens de ces crustacés,
un certain nombre de préparations et cartes relatives aux maladies qui les affec-
tent (peste, taches, etc.).
ge
Engins de péche. — I] ne semble pas qu'il y ait, en Russie, d’usines
importantes d’instruments de péche, tout au moins n’y en avait-il
guére qu’une dont les produits fussent mis en montre, celle de Jolnino,
dans le gouvernement de Nijni Novgorod. Elle appartient 4 MM. Gou-
riew et Sklialine, et occupe 2100 ouvriers ; on y fabrique des cordages
et des filets.
Ceci n’empéchait pas qu’iln’y eut de nombreux engins exposés, mais
ils l’étaient surtout par les particuliers ou les corporations (Cosaques de
l’Oural et de Kouban, commune du village Rybatskoé), propriétaires ou
locataires de pécheries importantes. D'une maniére générale ils parais-
seat étre fabriqués surtout par ceux qui les emploient et sont par suite
quelquefois un peu grossiers. Les plus employés sont'les filets harra-
ges, la senne, les nasses et verveux et enfin la foéne, cette derniére trés
en usage pour la péche sous la glace.
En ce qui concerne la péche a Ja ligne, le Musée Polytechnique de
Moscou exposait une intéressante collection d’engins fabriqués par des
paysans et amateurs en différents points du pays.
Produits de lapéche.— Le poisson sert principalement 4 1’alimenta-
tion et doit souvent, surtout en Russie, étre consommé fort loin du liew
ou ila été péché. D’ou la nécessité de lui faire subir une préparation
Je mettant a l’abri de Ja corruption. Il existe pour cela plusieurs pro-
cédés qui sont — la congélation — le fumage — la salaison — et la
stérilisation,
Congélation. — Dans un pays comme la Russie, ou Ia glace natu-
relle est généralement facile 4 obtenir en grandes quantités, le moyen
le plus pratique et le moins codteux pour empécher I’alfération des
substances alimentaires putrescible consiste 4 les soumettre A ]’action
du froid.C’est ainsi qu’on procéde, en particulier, 4 l’égard du poisson.
Congelé sur les lieux de péche, il est expédié ainsi dans les centres
de consommation ou on le conserve dans des glaciéres jusqu’au mo-
ment du besoin, On pouvait voir, dans la partie extérieure de l’Exposi-
tion, de beaux spécimens d’esturgeon et de saumon ainsi préparés.
Ce mode de conservation présente de grands avantages au point de
vue de I’économie, mais il ne va pas sans un léger inconvénient, En
l’absence de toute mesure préventive, le poisson peut, pendant le trans-
port subirun réchauffement et par suite un commencement d’altération.
Pour éviter ces accidents, un des exposants, M. Michel Podbereski,
_ propose un récipient de son invention, A l’intérieur duquel la tempéra -
ture se maintient contante sans étre influencée par celle de l’air am-
biant. Ce récipient, qui a été soumis par le jury a une épreuve sérieuse,
= §
parait devoir rendre des services pour le transport du poisson gelé,
et aussi des autres comestibles. II permettrait en particulier, entre la
Russie et la France ou l’Angleterre, des échanges de produits qui ne
peuvent jusqu’ici étre transportés a l'état frais.
Fumage. — lly a un certain nombre d’espéces d’eau douce dont la
chair est fumée a peu prés dans les méme conditions que celle du
hareng; ce sont en particulier l’esturgeon, le sténode nelma, la bréme
wimba, I’anguille, le saumon. Pour ce dernier, on pratique d’ordinaire
le fumage a froid.
Cette préparation facile ‘et peu dispendieuse est trés courante; tous
les exposants de la section des produits de péche avaient en montre
diverses sortes de poissons fumés.
Salaison. — La salaison est en Russie le moyen le plus employé
pour la conservation du poisson de tout genre. Prés des pécheries impor-
tantesexistentdes batiments spéciaux pour cette opération, des plans, des
modeéles en relief et des vues de quelques-unes figuraient 4 l’exposition.
fl convient de citer 4 ce propos les deux panoramas représentant
les ateliers de préparation du poisson appartenant respectivement a
M. Bezzoubikow et 4 MM. Sapojnikow fréres, d’Astrakhan.
Quant aux produits ainsi obtenus,ils étaient exhibés en grande quan-
tité dans des tonneaux dont un disque en verre remplagait la bonde.
Anguilles, brémes, carpes, brochets, perches, etc., y étaient empilés en
couronne dans la saumure, et on pouvait admirer et leur taille, et leur
parfaite conservation ; la préparation n’ayant altéré qu’a peine les cou-
leurs et la forme des corps.
Stérilisation. — Les conserves en boite sont surtout 'préparées avec
du poisson de mer. Bien qu’on puisse traiter de la méme maniére plu-
sieurs espéces d’eau douce, cette pratiquen’est pas trés répanduecen Russie.
Cependant dans l'importante exposition de la maison A. K, Doubinine,
d’Odessa, il se trouvait, entre autres, quelques spécimens de ‘conserves
d’esturgeon et de pleuronecte.
La chair du poisson n’est pas le seul produitqu’il fournissea l’alimen-
tation, les ceufs de certaines espéces sont comestibles, et servent A la
fabrication du caviar. On emploie d’ordinaire ceux de Vesturgeon, mais
ceux d’autres poissons, de la sandre, par exemple, peuvent aussi con-
venir. Ce produit, trés recherché, fait l’objet d’un commerce important, et
occupait une place notable parmi ceux de la section russe. Mais, quelle
que soit sa réputation trés légitime, on ne peut s'empécher de regretter
Ja destruction de quantités énormes de frai 4 laquelle donne lieu sa pre-
— a
paration, et le dépeuplement des riviéres qui en est la conséquence.
Il reste enfin 4 signaler, comme produits accessoires de la péche en
Russie, la colle, l’huile et la farine de poisson, fabriquées dans des usi-
nes annexes de pécheries importantes.
Pisciculture artificielle. — Les procédés dela pisciculture sont loin
d’étre inconnus en Russie, et c’est d’ailleurs 4 un Russe, Wrasski (r),
qu’on doit la méthode presque universellement employée aujourd’hui
pour la fécondation artificielle.
Outre les plans, croquis et photographies d’un certain nombre d’éta-
blissements, plusieurs installations pour T'incubation des ceufs de
salmonide figuraient a l’exposition, et, l’époque le permettant, les appa-
reils ont été ‘presque toujours présentés en fonctionnement, c’est-a-dire
contenant des ceufs embryonnés et des alevins 4 divers états de dévelop-
pement. Les plus importantes et les mieux aménagées de ces instal-
lations étaient celles du Baron Staél de Holstein, 4 Novo-Anzen; de
M. Kirsch, & Aalt-Salis; de la Section livonienne de la Société Impé-
riale Russe de Péche et Pisciculture; et du Ministére de l’Agriculture
et des Domaines (Etablissements de Nikolsk et Louga).
Les auges en usage en Russie pour la truite et le saumon ne se dis-
tinguent par aucune particularité, elles sont du type Coste ou Von den
Borne (2). Les appareils pour l’incubation des ceufs de corégone présentent
une certaine diversité bien qu’étant tous basés sur le méme principe;
cété de celui de Zug proprement dit, on emploie des dispositifs dont le
croquis est figuré ci-dessous,
Etablissement de Louga. Etablissement d’Aalt-Salis,
I] était naturel de tenter en Russie Ja propagation artificielle du plus
intéressant peut-étre des poissons du pays, c’est-d-dire de l’esturgeon,
dont il est fait une péche si active et en particulier au moment du frai
4. — Les appareils ayant servi aux recherches de Wrasski figuraient a l’exposi-
tion de l’établissement de pisciculture de Nikolsk.
2.— A l’établissement de Louga, dirigé par M. Bippen, on pratique l’incubation
des ceufs de saumon dans l’atmosphére humide.
*
—- 10 —
pour la préparation du caviar. C’est ce qui a été fait par M. Borodine,
spécialiste en chef de pisciculture au Ministére de l’Agriculture. Il a
réussi la fécondation artificielle de Vesturgeon étoilé et de l’esturgeon
_Tusse, et Vincubation des ceufs dans des boites flottantes de Seth-Green.
“Les travaux publiés A ce sujet, ainsi que les appareils employés, des
collections d’ceufs et d’alevins A différents états de développement, per-
mettaient aux visiteurs de l’exposition de se rendre compte de la mar-
che et des résultats de cette,trés intéressante expérience.
Etangs. — L’élevage de la carpe en eaux closes a une certaine impor-
tance dans les provinces occidentales de la Russie.
Une exposition intéressante, 4 ce point de vue, était celle du
Baron K. de Mandteuffel, de Katzdangen, Courlande. Un plan en relief
renseignant d’abord sur l’aménagement et la disposition des étangs, de
pose et d’accroissement, puis des aquariums contenant des sujets de
differents Ages mettaient en évidence les résultats obtenus par la mé-
thode d’élevage. Celle-ci consiste 4 assurer toujours au poisson une
nourriture abondante en le faisant passer dans une série d’étangs mis en
eau successivement au fur et 4 mesure de son développement. Les spé-
cimens exhibés étaient des carpes ordinaires et des carpes amiroir de 1,
2, 3 et g ans pesant respectivement 500, rooo, 1750 et 7500 grammes.
Il n’y avait pas de différence apparente entre les deux variétés, au point
de vue de la croissanee.
A cette question des étangs se rattache celle des ouvrages de retenue.
Dans cet ordre d’idées une mention est due aux écluses automatiques
Tekor Elkor, exposées en modéles réduits, 4 courant d’eau.
Ces écluses, inventées par M. Skotnitzki et le Comte Ostrowski, sont
des appareils destinés 4 maintenir constant, en toutes circonstances, le
niveau d’un étang ou d'un bief de riviére. Elles tendent donc A éviter,
en cas de crue méme subite, l’inondation des propriétés situées en
amont du barrage, et & rendre impossible les abus souvent commis par
les usiniers en laissant l’eau dépasser, dans les canaux d’amenée, la
hauteur réglementaire,
La vanne Elkor est une vanne 4 flotteur; suivant la position de ce
dernier en aval ou en amont du piquet supportant l’axe du sytéme, la
pelle s’ouvre en montant ou en descendant. Dans ce second cas,la vanne,
moins haute, coulisse devant une partie fixe formant seuil; l’eau en
excés s’écoule comme au-dessus d’un déversoir. De cette facgon il n’y a
pas de poisson cntrainé, celui-ci se tenant presque toujours sur le fond.
— II —
Le type n° 1 convient donc pour les riviéres, le type n° 2 pourles étangs.
Ce systéme présente Vavantage de s’ouvrir dés que le flotteur est sou-
Rant
P77 DELLA E ED
Vanne Elkor n° 1.
:
Jevé, donc, en cas de crue subite, avant que le flot de cette crue n’attei-
gne l’ouvrage de retenue; celui-ci n’a donc a supporter qu’un choc atté-
nué. L’atténuation est encore plus sensible si la pelle est formée d’un
cadre avec volet se rabattant vers l’aval. Ce volet est d’ordinaire fermé
par un verrou, maisvienne une forte augmentation du niveau en amont,
le flotteur agit, non seulement sur la vanne entiére, mais encore sur le
verrou au moyen d’une chaine, le volet est chassé en avant et I’écoule-
ment se fait sans obstacle.
La vanne Tekor repose sur un autre principe. C’est une porte mobile
autour d’un axe horizontal situé & une certaine hauteur au-dessus du
seuil. Cettehauteur estcalculde de telle fagon que, pour un niveau donné
en amont, les pressions sur les parties
supérieure et inférieure s’équilibrent; si
Peau vient 4 monter, l’équilibre étant
détruit, la porte bascule, et l’eau s’é-
chappe par enhaut et par en bas tant que
le niveau fixé est dépassé. En cas de crue
violente la vanne s’abat complétement.
Vanne Tekor. Ce second type est applicable, a la dif-
férence des deux autres,. aux riviéres
flottables ou susceptibles de charrier des glacgons.
Ce systéme de vannes automatiques, séduisant en théorie, est-il vrai-
ment pratique ? C’est ce qu'on ne peut conclure du bon fonctionnement
des modéles réduits exposés. Il faudrait pour cela étudier les quelques
installations existant actuellement en Pologne.
Mais comme sans doute les brevets pris dans les différents pays ne
—i13—
tarderont pas a étre exploités, il est probable qu’on pourra bientdt, en
France méme, apprécier, la valeur réelle des écluses Tekor-Elkor.
Recherches scientifiques. — Le courant d’idées qui, dans tous’ les
pays, porte actuellement l’attention des savants vers l'étude des eaux
s'est fait sentir en Russie comme ailleurs, et d’autant mieux que la péche
fluviale et lacustre y a plus d’importance. On pouvait apprécier, a l’ex-
position, par les ouvrages, plans, diagrammes, etc., mis sous les yeux
du public, le nombre, la nature et ]’intérét des recherches entreprises.
Ces recherches ont été effectuées par les soins de I’Etat ou sous les
auspices de plusieurs Sociétés.
Le premier posséde 4 Nikolsk, gouvernement de Novgorod, un labo-
ratoire d’ichthyologie annexé 4 I’établissement de pisciculture et dépen-
dant comme lui du ministére de 1l’Agriculture et des Domaines. Ce
laboratoire est doté d’un beau matériel, 4 en juger par les microscopes,
appareils de projection et photographie, instruments de sondage et de
péche qui se trouvaient exposés. A cété, figuraient des collections bota-
niques et zoologiques et les comptes-rendus des travaux. Ces derniers
ont portt jusqu'ici surtout sur les lacs et consisté en analyses chimiques
et biologiques de l’eau et du sol, études des organismes du plankton et
sondages thermométriques.
Ce sont des recherches analogues et concernant également les eaux
lacustres qui ont été exécutées par les membres — de la Commission
permanente pour l'étude des lacs de Russie — de l’expédition zoolo-
gique du lac Baikal — de la Section d’ichthyologie de Moscou de la
Société Impériale Russe d’acclimatation — de la Station hydrobiologique
du lac Profond.
Quant aux riviéres, les travaux les plus importants sont ceux de la
Station biologique du Volga de la Société des naturalistes de Saratow,
qui exposait des collections de poissons, d’orgauismes leur servant de
nourriture, et d’animaux qui au contraire leur sont nuisibles. Il faut
aussi mentionner les cartes dressées par les soins de la Société impériale
Russe de Pisciculture et de Péche, et relatives, l’unea la propagation
dela peste de l’écrevisse, l’autre 4 la distribution géographique des
différentes espéces de poissons,
A propos de cette derniére Sociéte, il convient de rappeler que c'est
a elle qu’est due l’organisation de l'Exposition Internationale, et que
revient par conséquent l’honneur de son succés en général, et en parti- -
culier celui de la section russe.
ae |
FINLANDE
Le Grand-Duché de Finlande est la région de l’Europe la plus riche
en eaux intérieures puisque celles-ci y couvrent 11 o/o de la super-
ficie totale du pays. Les poissons qui les fréquentent sont principale-
ment — dans les lacs : le corégone blanchatre,l’éperlan, Je lavaret, et
le saumon lacustre (Salmo eriox. L) — dans les riviéres : le saumon
ordinaire, la truite de ruisseau, l’ombre commun et la lamproie fluvia-
tile. L’écrevisse est abondante dans le centre et Je sud du pays.
Les engins employés pour la péche sont surtout des filets du genre
senne, dont quelques spécimens figuraient a l’exposition. Sur les cours
d’vau sont aussi installées des pécheries, dites « pator » consistant en
barrages de formes différentes conduisant le poisson A des nasses ou
il reste prisonnier, ou 4 une sorte d’enclos ou il se rassemble et est
capturé au filet. Ces pécheries sont surtout aménagées pour prendre le
saumon.
Le poisson est généralement salé fortement, quelquefois fumé (la-
varet, éperlan, anguille et sanmon). Le grillage et le marinage de la
lamproie de riviére sont l’objet d’une industrie assez importante dans la
partie occidentale de la province.
La grande surface occupée par les lacs a naturellement amené a
chercher les moyens de leur faire produire,en ce qui concerne la péche,
tout le rendement dont ils sont susceptibles. Une station d’essais a été
créée dans ce but, a I’Institut Forestier d’Evois, en 1892, avec un budget
annuel de 1700 francs.
L’exposition de cette Station était certainement, en ce qui concerne
les eaux douces, la plus remarquable de la section finlandaise. Elle fai-
sait connaitre d’abord par des cartes et plans l’établissement et son
domaine, puis les travaux accomplis et les résultats obtenus jusqu’A ce
jour, et ces résultats, exposés dans une brochure de M. le Professeur
Bernhard Ericsson, présentent beaucoup d’intérét.
Pour favoriser la reproduction naturelle, des frayéres artificielles ont
été établies en grand nombre. Pour les poissons d’été on a planté dans
des criques tranquilles et ensoleillées, des pieux disposés en cercle entre
lesquels ont été disposés des genévriers et petits sapins, de la maniére
indiquée par la figure ci-aprés. Pour le lavaret, la frayére est faite de
pierres et de gravier. Enfin, en certains endroits fréquentés par la bréme
au moment de la ponte, des signaux ont été disposés pour empécher
Sth
Enfin deux ou trois cartes ichthyographiques, et d’assez nombreuses
publications, parmi lesquelles il faut citer les études de M. le Dr Wei-
gelt sur la pollution des riviéres et leur dépeuplement, complétaient Ja
partie de l’exposition allemande concernant la Péche fluviale.
Cette partie n’avait donc pas, A beaucoup prés, l’importance qu’elle
aurait di avoir et ne permettait de se rendre compte qu’imparfaitement
des efforts et travaux sérieux entrepris en Allemagne pour l’exploitation
rationnelle, la mise en valeur et l’étude des eaux douces.
Pour cette section, comme pour une ou deux autres, |’Exposition de
Vienne, qui devait s’ouvrir six mois plus tard, a fait tort a celle de
Saint-Pétersbourg.
JAPON
L’emplacement de la section japonaise était un carré d'une dizaine de
métresde cété, au milieu duquel se dressait un kiosque élégant orné de
drapeaux et éclairé de lampes électriques blanches et rouges. L’ensemble
avait beaucoup de cachet, la décoration était heureuse et l’aménagement
trés soigné.
L’Empire du Japon étant composé d'fles, la péche maritime y occupe
naturellement une place trés prépondérante; mais la péche fluviale ne
semble pas négligée, 4 en juger tout au moins par les superbes engins
figurant a l’exposition.
Une partie de ces engins étaient des filets de formes diverses, d’une
exécution parfaite, fabriqués au moyen d’un fil a la fois trés mince et
trés résistant ; des substances tannantes et colorantes leur donnent de la
durée et les rendent presque invisibles pour le poisson. Mais les cannes
a péche surtout méritaient ’attention ; légéres,solides et élastiques,par-
faitement équilibrées, elles réunissaient toutes les qualités requises. Il
y en avait de plusieurs types, dont l’un, particulisrement remarquable,
composé de piéces rentrant les unes dans les autres, et paraissaient faites
d’une sorte de bambou ou roseau. A cété d’elles se voyaient des lignes,
hamegons, poissons d’étain, mouches artificielles, etc., d’une exécution
non moins irréprochable. Tous ces engins, sortis pour la plupart d’ate-
liers de Tokio, soutenaient dignement Ja réputation de l'industrie japo-
naise, si consciencieuse et si soigneuse des détails.
La pisciculture artificielle est pratiquée auJapon, la propagation du
saumony a été essayée par ses procédés. Des comptes rendus publiés 4
ce sujet par |’'Institut impérial de péche de Tokio figuraient 4 l’exposi-
tion, ainsi que des photographies de l’établissement de Chitose.
am ae
Il était enfin impossible de visiter la section sans s’arréter a feuilleter
un superbe album d’aquarelles. Les différents poissons de la faune du
pays y étaient représentés, dans les attitudes naturelles de la vie, avec
une précision de dessin et une fidélité de couleur admirables. C’étaient
ala fois des figures pour ouvrages de science et de véritables ceuvres
dart.
Avec de pareils éléments et il n’en manquait pas. de semblables dans
la partie consacrée a la péche maritime la section japonaise devait avoir
et aeu du succés. N’attirait-elle pas tous les visiteurs, les amateurs, par
Vintérét réel qu’elle présentait, et les simples curieux par le cachet
artistique de son installation ?
ROUMANIE
Il n’y avait presque rien, la section roumaine, en dehors de |’exposi-
tion de la Direction des péches de Bucarest qui renseignait d’ailleurs
fort bien sur les ressources présentées par les eaux courantes de la
région du Bas-Danube, la maniére dont elles sont exploitées, et le parti
qu’on en tire.
Les poissons qui peuplent ces eaux étaient mis sous les yeux du public
soit conservés dans du formol, soit empaillés pour ceux de grande taille,
comme l’esturgeon et le silure. Différents modéles en relief de sections
de ruisseaux et bords de riviéres, avec galets, sable, plantes terrestres
ou aquatiques, et glace figurant le niveau de |’eau, faisaient en outre
connaitre les animaux ichthyophages du pays et notamment les oiseaux.
Les engins de capture da poisson sont des filets et des pécheries. Les
premiers, et particuliérement des sennes, étaient disposés en draperies
le long des murs et servaient ainsi a la décoration. Quant aux pécheriés,
qui consistent en barrages de types divers, mais ayant ce caractére
commun d’avoir des issues aboutissant 4 des pidges elles étaient repré-
sentées par une série de superbes photographies.
Les produits de la péche, dont les spécimens étaient assez nombreux,
sont 4 peu prés les mémes qu’en Russie, ils consistent en poisson salé
et fumé, caviar et colle d’esturgeon.
L’exposition roumaine avait été organisée avec soin, et, bien que
d’étendue restreinte, donnait pourtant une idée complete de état de l’in-
dustrie de la péche dans un pays ou elle a une notable importance.
——- 17
SIAM
La participation du Ministére des Affaires Intérieures du Royaume de
Siam 4 l’Exposition de péche avait valu a celle-ci une section trés cu-
rieuse, qui occupait, vis-a-vis de celle du Japon, une surface presque
double.
Le clou de cette section était, 4 l’intéricur d’une sorte de pagode, un
petit panorama fort bien rendu, représentant un village de pécheurs
avec huttes baties sur de hauts pilotis, barques 4 la chaine et filets au
séchage. Le public s’y portait en foule, et c’était justice, mais les cing
grandes vitrines qui l'entouraient méritaient mieux qu’un coup d’ail.
Elles renfermaient, en effet, une curieuse collection de modéles réduits
de barques et instruments de péche. Ces derniers consistent en nasses, filets,
gords, etc., dont Je type a bien quelques rapports avec celui des engins
employés en Europe, mais dont la forme est toujours spéciale, souvent
étrange. Les dispositifs compliqués adoptés par les pécheurs siamois
ont-ils une raison d’éire dans le pays? Peut-étre... En tous cas on ne
pouvait s’empécher d’admirer Vingéniosité et la fantaisie qui ont pré-
sidé 4 leur invention, et aussi le talent des ouvriers qui les ont repro-
duits avec un admirable souci du détail.
De toutes les sections étrangéres, celle du Royaume de Siam était sans
contredit la plus originale.
FRANCE
La surface de l’exposition frangaise atteignait presque 300 métres car-
rés, c'est dire son importance, due a la participation de deux ministéres,
ceux de l’Agriculture et de la Marine, de plusieurs sociétés et de nom-
breux particuliers. Son intérét n’était pas moindre, grace d’abord 4 son
aménagement bien compris, 4 son élégante décoration, grace surtout &
la variété des objets et produits qui y figuraient. Comment la variété
aurait-elle d’aillears fait défaut, quand la France est baignée par des
mers et arrosée par des fleuves d’allures si différentes ?
Rien n’avait été négligé pour donner une idée de la fagon dont sont
exploitées et mises en valeur les eaux frangaises ; il en était particulié-
rement ainsi en ce qui concerne la péche fluviale.
Les poissons deslacs et riviéres étaient représentés par la collection de
sujets naturalisés de l’Ecole Forestiére des Barres. Dans le méme ordre
d'idées la Société Centrale d’Aquiculture et de Péche avait fait exécuter
= 18 —
toute une série d’aquarelles, reproductions a la fois fidéles et artistiques
de toutes les espéces les plus importantes.
Pour les engins de péche, ils étaient presque tous décrits, et la plupart
figurés dans un ouvrage donnantles résultats d’une enquéte ouverte sur
ce sujet par M. Daubrée, Directeur général des Eaux et Foréts.Le public
pouvait en consulter des exemplaires mis a sa disposition, et, en outre,
examiner les collections de l’Ecole Nationale Forestiére de Nancy, con-
sistant en grandes photographies et plans en relief représentant divers
types de pécheries, et en petits modéles, avec figurines, renseignant sur
la forme et le mode d’emploi de l’araignée, du baro, du carrelet, de
l’épervier, de la senne, du tramail, de la trouble et des -verveux.
Plusieurs fabricants avaient aussi exposé et envoyé a Saint-Péters-
bourg, qui des filets, qui des articles de péche a la ligne. Ces derniers
surtout attiraient l’attention, et cependant, il faut bien l’avouer, ils n’ont
pas eu tout le succés auquel on aurait pu s’attendre dans une exposition
4 laquelle ne prenaient pas part les maisons anglaises. Les industriels
frangais avaient-ils craint de faire voyager au loin leurs piéces les plus
soignées ? Celles-ci avaient-elles subi des détériorations en cours de
route ? En tous cas le jury a eu 4 constater quelques légéres défectuosi-
tés, et c’est ainsi que les récompenses accordées par lui n’ont pas été ce
qu elles auraient pu étre. )
La place occupée pour la pisciculture était peut-étre un peu restreinte.
Cependant un plan relief, fort bien exécuté, figurait l'ensemble de l’im-
portant élablissement crééa Bessemont (Aisne) par M.de Marcillac; des
croquis et photographies en faisaient connattre le détail. La station aqui-
cole du Nid du Verdier, dirigée par M. Raveret Wattel, était repré-
sentée par un plan. Des vues de quelques autres établissements accom-
pagnaient l’exposition d’auges 4 incubation, bacs flottants et appareils
pour transport d’alevins dela maison Dagry, de Paris.
Les différents types d’ouvrages destinés 4 permettre aux poissons
migrateurs la remonte des barrages, savoir — rigole inclinée — escalier
— échelles des systémes Mac Donald, Brackett et Caméré — se trou-
vaient réunis sur un méme modéle, a circulation d’ean, permettant d’ap-
précier leur mode de fonctionnement..
La culture des étangs, nombreux pourtant en France, est loin d’étre
pratiquée d’une maniére aussi rationnelle et intensive que dans plusieurs
pays voisins, cependant leur aménagement présente souvent des parti-.
cularités intéressantes. On pouvait s’en rendre compte grace a deux
plans relief représentant — ]’un une pécherie a gradins, avec guideaux,
ou s’effectue une sorte de triage automatique du poisson qui y est
=e
entrainé par le courant —l’autreun étang dela Dombes (Ain) au moment
de l’assec, avec son systéme de biefs et faux biefs, poéle, riviére de cein-
ture, thous, embies et ébiesde différents types.
Enfin, en ce qui concerne les études et recherches scientifiques, i]
convient de signaler, outre les publications, la belle collection de piéces
ichthyologiques de la maison Deyrolle,de Paris, et le sondeur E. Belloc,
a fil d’acier, quia deja rendu bien des services pour Jes recherches
lacustres.
A cété de la partie concernant la’ péche fluviale, celle relative a la
péche maritime ne présentait ni une moindre importance, ni un moin-
dre intérét, l'ensemble était 4 la fois agréable et instructif. Le public est
venu nombreux, il est permis d’espérer qu’il a apprécié le coté attrayant
comme le cété sérieux et emporté, de sa visite 4 la section francaise,
une impression favorable et un bon souvenir.
AUTRES NATIONS
Outre Jes sections dont il a été question dans ce qui précéde, il en
était d’autres, celles du Danemark, de l’Egypte, de la Principauté de
Monaco, de la Norvége, de la Perse et de la Suéde, qui ne présentaient
rien d’intéressant au point de vue de la péche fluviale.
De plus, quelques nationaux autrichiens,belges, espagnols, indiens et.
italiens avaient participé a l’exposition. On peut meationner parmi les
objets, produits et travaux envoyés par ces derniers,les poissons natura-
lisés de MM. Lenoir et Forster,de Vienne; les trés belles collections de la
Société de péche et pisciculture de Cracovie, faisantconnaftre la faune
aquatique de la Galicie, les engins et bateaux qui y sont employés et les
appareils d’incubation en usage; enfin les soies pour lignes de M. Am-
brosano, a Procida.
L’examen détaillé de diverses sections de l’Exposition internationale de
Saint-Pétersbourg montre qu’elle présentait plus d’un élément de succés
et ce dernier a répondu a l’attente et aux efforts déployés.
Jusqu’au dernier jour la foule est venue, nombreuse, animer le vaste
manége Michel.Sila voguen’a pas été passagére,c’est que le public, sensible
sans doute a l’attrait du décor, a pris un réel intérét au spectacle mis
Sous ses yeux. L’Exposition, eneffet, a été non seulement brillante, mais
instructive ; en la parcourant on pouvait acquérir des notions sur la si-
tuation et les progrés récents de l'industrie des péches dans les différents
— 20
pays, et il y avait la matiére 4 fructueuses comparaisons. Ce but élevé
et pratique a été pleinement atteint, grace aux heureuses dispositions
adoptées par les organisateurs pour la division, l’aménagement et le
classement. M. le Docteur Grimm et ses collaborateurs du Comité gé-
rant,qui n’ont ménagé ni leur temps ni leur peine, ont su joindre lutile
et l’agréable ; quoi d’étonnant 4 ce que leur ceuvre ait mérité tous les
suffrages ?
Extrait de la Revur pes Eaux zt Forérs, des 15 Avril,
qe" et 15 Mai 1903.
Poitiers. — Imp. Bais et Roy
Extrait du Bulletin mensuel des séances de la Société des Sciences de Nancy.
L’Epicéa du Charmois, par M. pe Drouin ve Bovvitte, Garde gé-
néral attaché & la Station d’expériences et recherches de l’Ecole
nationale des eaux et foréts.
Le chéteau du Charmois est situé dans le voisinage immédiat
de Nancy, sur le territoire de la commune de Vandceuvre, ow il
occupe le sommet d’une ondulation séparant les vallons des ruis-
seaux de Saurupt et de la Madelaine. I] est entouré d’un pare d’une
contenance d’a peu prés quatre hectares, planté d’arbres d’ornement
dont les plus vieux paraissent dgés d’une soixantaine d’années.
Parmi ces derniers se trouvent plusieurs épicéas (Picea excelsa
Link) dont un, relativement isolé au milieu d’une petite pelouse,
attire attention dés le premier coup d’ceil(*). C’est une masse
imposante de verdure, particulitrement dense vers sa moitié
inférieure (Voir Pl. I). Vient-on 4 s’approcher, on distingue tout
autour de l’arbre principal, haut de 20 4 22 métres, un certain
nombre d’autres tiges de 4 4 10 métres d’élévation, et auxquelles
est dé le facies particulier de cet épicéa (Voir Pl. II et III).
Bien qu’émergeant verticalement du feuillage de ce dernier, les
tiges en question paraissent au premier abord en étre parfaitement
distinctes. Il faut pénétrer sous l’arbre lui-méme pour se rendre
compte, non sans quelque étonnement, qu’on se trouve en présence
de marcottes. Parmi les branches basses ayant pris contact avec
le sol, huit se sont enracinées plus ou moins fortement. De 1a la
formation d’une dizaine de tiges secondaires vigoureuses, franche-
ment dressées, 2 rameaux disposés en verticilles, se comportant
(1) Deux autres épicéas, semblant dater de la méme époque que celui faisant
Vobjet de cette étude, paraissent mériter une mention. Leur port est tres spécial, les
branches basses se redressent verticalement en constituant, chez l'un d’eux surtout, de
véritables fleches; les autres branches sont normales. Ces arbres sont situés pres du
chateau et ont respectivement 2™,20 ef 2™,90 de circonférence 4 hauteur d’homme.
—_—_— 2—
absolument comme des individus isolés, mais restés en relation
avec le tronc parent (Voir Pl. IV).
Le marcottage artificiel de l’épicéa, bien que peu pratiqué, est
cependant chose possible(*), mais le marcottage naturel est trés
rare (7), Pourtant les circonstances paraissent souvent le favoriser.
Combien n’existe-t-il pas, dans les parcs surtout, d’épicéas ayant
développé des branches basses vigoureuses qui trainent sur le
sol ou sont méme plus ou moins enterrées dans l’humus? Com-
ment, dans ces conditions, ne se produit-il qu’exceptionnellement
des racines adventives (3)? La chose est singuliére, en tous cas la
rareté du phénoméne rend intéressants les quelques arbres chez
lesquels on le constate, c’est pourquoi celui du Charmois, ot la
faculté d’enracinement des branches est trés caractérisée, parait
mériter une courte étude.
Le premier examen révéle |’existence de marcottes, reste 4 con-
naitre, d’une fagon précise, leur disposition par rapport au tronc,
les points d’insertion des branches enracinées, les emplacements
des tiges secondaires, enfin les dimensions respectives des unes
et des autres. Dans ce but a été dressé le plan reproduit ci-aprés
que complétent les chiffres des mesures effectuées, consignés dans
le tableau suivant.
(1) Voir Carntkne, Traité général des coniferes. Paris, 1867.
(2) Le seul épicéa analogue 4 celui du Charmois, signalé jusqu’ici en France, est
celui du parc de Barville (Eure); il avait, en 1890, 29™,50 de hauteur, 3™,60 de cir-
conférence A 1 métre du sol et présentait dix-huit branches enracinées dont une donnant
naissance a trois fleches. La plus grosse des tiges sccondaires, distante de 5™,50 du
tronc principal, avait alors 1™,35 de tour 4 hautcur de poitrine. (Henry-Queviniy, « Cu-
riosités végétales de Barville pres Thiberville », dans l’Annuaire normand. Caen et
Rouen, 1884. — H. Gapeau ve Kerviute, Les Vieux arbres de la Normandie, fasci-
cule I. Paris, Bailligre, 1891.)
~ Dune fagon générale, le marcoltage naturel est rare chez les résineux; on I’a cons-
taté cependant aussi chez le Picea nigra Doumetii, du parc de Baleine (Allier) [Charles
Batter, De laction du froid sur les végétaux ; Paris, J. Tremblay, 1882, p. 299] et
chez un Thuya gigantea du domaine d'Harcourt (R. Hicker et L. Panpt, Feuille des
jeunes naturalistes, 1°* octobre 1902).
(3) Il semblerait, d’apres une observation faite par M. le Garde général Guinier, que
la facullé d’émettre des racines adventives soit plus développée sur le tronc que sur
les rameaux. Un épicéa de Ja forét de la Grande Chartreuse, canton de Malissart, situé
sur les bords d’un torrent, se trouva lors d’une lave enlisé jusqu’A une hauteur de 2 me-
tres par la boue. Plusieurs années plus tard une crue d’eau claire dégageait le pied de
Parbre. On constatait alors que celui-ci possédait sur le tronc un enracinement situé &
peu prés a la hauteur ow s’élevaient les terres charriées, enracinement qui s’était formé
apres leur depét; sur les branches qui avaient été partiellement enterrées on ne remar-
quait pas trace de racines adventives.
Une remarque analogue a été faite en Suisse par M. F. Fankhauser (Journal fores-
lier suisse, numéro de décembre 1900).
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L’examen des données qui précédent démontre l’existence, chez
larbre étudié, d’une faculté de marcottage trés développée. II
présente en effet actuellement huit branches enracinées(*), ap-
partenant a six verticilles différents du tronc (?); et le nombre en
serait probablement plus grand si l’extrémité de plusieurs rameaux
trainant sur le sol n’avait été coupée en fauchant l’herbe de la pe-
louse environnante.De plus trois de ces branches ont formé cha-
cune deux tiges secondaires.
Chez la premiére (4), aprés son enracinement, un rameau latéral
(devenu par suite une branche de la fléche E) s’est enraciné son
tour, donnant naissance a la tige D qu’on peut, par suite, qualifier
de tertiaire.
La branche 5 produit la tige F, tandis qu’un rameau, qui se
détache d’elle avant son point de contact avec le sol, forme la
fléche G.
Enfin, sur la branche 8, il n’y a qu’un enracinement, mais son
extrémité n’est pas seule A s’étre redressée, un rameau latéral en
a fait autant ; il ya ainsi deux tiges secondaires L et M possédant
une souche commune.
Si on ajoute a ce qui précéde que le sol est argileux, assez
compact, et normalement sec a l’abri de l’épicéa, il faut recon-
naitre a celui-ci une faculté d’enracinement des branches tout a
fait particuliére.
Cette faculté constitue bien une qualité propre, intrinséque de
larbre du Charmois, les circonstances extérieures ne paraissent
en effet V’influencer en rien. On vient de voir que le terrain était
peu favorable au développement des racines adventives, le rdle de
Vinsolation parait nul, tout au moins l’orientation des branches
est-elle indifférente (3). Sien effet la plupart de celles qui sont mar-
cottées se trouvent a l’ouest d’une ligne nord-sud passant par le
tronc principal, il en est une (g) qui se dirige franchement vers
Pest. De plus, comme il a été déja dit, on peut constater dans le
secteur sud-est que lextrémité d’un certain nombre de branches
(1) Une neuvigme (7) donne une tige secondaire (K) sans étre encore enracinéc.
Parmi les branches insérées sur le tronec entre Je sol et 1™,50 de hauteur qui subsis-
tent encore aujourd’hui, il n’y en a que deux qui ne soient pas marcottées,
(2) Les verticilles sont compris entre 0™,35 et 1™,50 de hauleur au-dessus du sol,
trois d’entre eux présentent deux branches marcottées, les trois autres n’en ont qu’une.
(3) Il est probable en effet que la situation isolée de I’épicéa n’est pas sans influence;
en massif, le méme arbre ne se serait peut étre’ pas marcotleé.
des
basses a été coupée, ce quia empéché la formation de tiges secon-
daires. La production de ces derniéres n’est enfin pas la consé-
quence d’un état méme passager de langueur ou de dépérissement
du tronc principal, contre lequel une réaction aurait eu lieu chez
les branches convenablement situées pour s’alimenter directement
au sol. Sur toute sa hauteur l’épicéa étudié a une superbe végéta-
tion et les tiges secondaires datent d’époques différentes.
C’est donc 4 l’examen de I’arbre lui-méme qu’il faut demander
la raison de cette propriété qu’il posséde d’émettre des racines
adventives sur presque tous les points oi ses branches, voire ses
rameaux, sont en contact avec le sol. Pour cela il convient de se
rendre compte de la fagon dont se produit cet enracinement qui
peut étre, soit antérieur, soit postérieur a la formation des tiges se-
condaires.
L’observation d’une branche tratnante, non encore enracinée
(7) mais a fléche déja nettement formée (K), conduit 4 penser que
le redressement des extrémités des branches et rameaux a toujours
précédé leur ancrage au sol au moyen de racines. Cette opinion
est confirmée par l’examen de la forme méme des branches, qui, au
moins dans la partie basse du tronc, s’inclinent d’abord vers le sol
a partir de leur point d’insertion, puis se relévent plus ou moins
franchement; plusieurs se terminent ainsi par une partie presque
verticale garnie de verticilles complets et bien feuillés.
Il semble dés lors que les choses se soient passées de la fagon
suivante. Tous les bourgeons latéraux de l’extrémité d’un rameau
venant a bien, alors que normalement un certain nombre avortent,
il faut A ce rameau plus de nourriture qu’a un autre, et d’autant
plus qu’il s’est développé de verticilles. Il arrive donc un mo-
ment ou le tronc ne suffit plus 4 alimenter la branche qui, alors,
ou se dénude, ou, si la chose est possible, c’est-a-dire s’il y a
contact avec le sol, émet des racines adventives(*). Une fois l’en-
racinement constitué, non seulement la tige secondaire ainsi
constituée peut végéter convenablement, mais elle se développe
vigoureusement.
Dans le cas particulier de l’épicéa du Charmois la faculté de
(1) Ce contact s’établit d’ailleurs plus facilement chez les branches 4 rameaux en ver-
ticille que chez les autres, 4 cause du poids plus fort qui les entraine vers la terre. C’est
ainsi que sur l’arbre du Charmois des branches insérées 4 1™,25 et 1™,50 au-dessus du
sol se sont marcottées.
a
marcottage parait donc une conséquence du port de l’arbre, sans
qu'il soit toutefois possible de dire qu’elle en dépend exclusive-
ment. La courbure des branches, leur redressement et la présence
de verticilles 4 leur extrémité se ren-
contrent chez beaucoup d’épicéas
sans qu'il en résulte de marcottes.
Ces conditions, qui ne sont pas suf-
fisantes;, sont-elles au moins néces-
saires ? Elles ne sont pas en tous cas
indispensables pour |’émission de ra-
cines adventives, d’aprés une cons-
tatation faite par M. le Professeur
Fliche, aux environs de Sens, sur une
i branche trainante, étalée sur le sol,
jf a rameaux disposés dans un méme
plan (*). [Voir la figure.] Mais aucun
j redressement de l’extrémité ne sem-
ble devoir étre la conséquence de
Venracinement, tout au moins aucune
tendance a la formation d’une fléche
i ne se manifeste encore. I] est donc
! douteux qu’on soit en présence d’une
Beanohe diiptcés marcotte proprement dite, et jusqu’a
avec facings adventivess preuve du contraire on peut admettre
Prana apsstomrantD que la faculté de reproduction par
cette voie est réservée aux épicéas dont les branches basses,
aprés s’étre plus ou moins inclinées vers la terre, se relévent pres-
que verticalement. Cette conclusion n’a guére toutefois que la
valeur d’une hypothése, puisqu’elle ne résulte que d’observations
faites sur un seul sujet.
La conséquence du marcottage est la formation de tiges secon-
daires; toutes celles de Varbre du Charmois sont encore en
relation avec le tronc parent, mais il semble que cette relation
pourrait, chez les plus Agées, étre supprimée sans inconvénient,
(1) Cette branche provient d'un arbre du bois de Champétu, vanton des Terres-Blanches,
Agé de 40 A 45 ans, ayant une hauteur de 7 4 8 metres et une circonférence 4 hauteur
d’homme de 0,35; il présentait encore deux autres branches basses enracinées. De
nombreux épicéas voisins ont des rameaux trainants semblables et 4 demi enterrés, mais
ne présentent pas de racines adventives.
=.
car si la branche continue a vivre entre ses points d’insertion et
d’enracinement, elle ne sé déyeloppe pour ainsi dire plus. I] suffit
pour s’en rendre compte de comparer les grosseurs des branches
marcottées et non marcottées, les premiéres sont beaucoup plus
faibles. Il n’y a d’autre part aucun rapport entre le diamétre de
celles-ci et les dimensions des tiges secondaires auxquelles elles
ont donné naissance, et dont l’importance varie avec celle de leur
enracinement. Ces tiges s’individualisent de plus en plus et fini-
ront par se comporter exactement comme des sujets distincts du
tronc principal.
Ces jeunes épicéas qui entourent l’ancien se créeront-ils 4 leur
tour une ceinture de marcottes? La chose est possible, puisque
dans la reproduction par voie asexuée toutes les propriétés et
particularités se transmettent d’ordinaire sans altération, et qu’au-
cun obstacle ne s’oppose a !’extension de l’arbre sur la pelouse qui
Venvironne. Son évolution sera intéressante 4 suivre, et les don-
nées de la présente notice, sorte de procés-verbal de l’état actuel,
pourront servir plus tard 4 des comparaisons instructives. Quoi
quil advienne d’ailleurs, l’épicéa du Charmois constitue déja
maintenant, non seulement l’ornement d’un parc, mais une curio-
sité végétale qui mérite d’étre connue et signalée.
Nancy, imprimerie Berger-Levrault et Cie.
Vue d’ensemble
prise du coté Ouest
Tiges secondaires C a G
(Vue prise au Sud)
Jeune tige secondaire (N)
(Vue prise au Sud)
Ph iV;
E
Tige
fy
Branche 5
a2)
z
B
Marcottes
ue prise a Vintérieur de l’arbre)
=
a
BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERIGA
VOL. 13, PP. 233-252 pis. 40-43
—
i
GEOLOGICAL SECTION OF THE ROCKY MOUNTAINS IN:
NORTHERN ALASKA
BY
F. C. SCHRADER
ROCHESTER
PUBLISHED BY THE SOCIETY
Jury, 1902
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BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA
VOL. 13, PP. 238-252, PLS. 40-43 JULY 29, 1902
GEOLOGICAL SECTION OF THE ROCKY MOUNTAINS IN
NORTHERN ALASKA *
BY F. C. SCHRADER
(Presented before the Society January 2, 1902)
CONTENTS
i Page
Geography and topography... ...... cc cece eee cee ce cece teeter eee e ene nes 234
TM PONeYaliis osc i nie eanread de Rie MESES ARENT S Be Fee eee FES dee area, 2O4
Koy nikal provitiCes : secu soak face sued SEP esac ae eeeee eee tas tau 234
Motintalli provVineGssccs, seats en adenakw si iabd hans Raeea ge creas SS 235
Colville or Arctic Slope province ....... 0.6. eee cece eee eee ee tetas 236
Geological section; 24 4:5. suierces cv igadageuendaae teres Veiga dowel e ee eaae he ae 237
PaleOzOiGS ess s5h a eebeweany ss 4sa dhyekalaies deans ge eennee Oi Ay GEM aes pmesS 238
Skajit formation (Upper Silurian) ..... ...-....-- riyaeic- day ake Seie were giwtes 238
, Character and OCCUrTENCE.... 6.2 cee nee rete nett ent e ene 238
Structure ..............000e- danni Ree RT Gos GR RMON LEE ESSE Za eS 239
AGO. crneeiasnisee: since ood ede eteese ae tse setae Bee 239
Totsen series (Silurian).... 2.0... ccc cee cee ee cece eee teen ba eeee 239
Character and OCCUIYENCE..... 00. c cece eee et teeter cere eens 239
Strtietlive: syucesiecscaeicte ctihwete vee yaardemeh clare thos emeiied 240
APG. tc auikindadttsda g ODRMREE ET ER Pee IRR! Bae geese Uae eemots 240
Stuver series (pre- -Devantan’ ae ee ee 240
Character and occurrence.......0. cece cece ete nee ene teen te ees 240
GEriGtTeisdccmacececaaws Heel WhinebemsihlGs wekgmeeaete Gasset 240
AGO cr ddinke eaeeg gee Cee ochn san menienNeanaeh Cie al caneeues 241
Lisburne formation (Devonian)....... ...eeeeeee Ba a hentai dae meunaende 241
Character and occurrence..........- Hance cance enste Gamaen aek ae asian 241
SUMOUIPE ccao ad csee Se Weve See ee ee hb ee Sea E es Dien eg ae 241
Noe sca dating naavientanaeauee sab Giada asbedilacs oie enn ay eomemaaeet 241
Fickett series (Lower Carboniferous)..... 666. 06 veer eee e ee cee eee ee 242
Character and OCCUITENCE.... 0. . cee eect eee eee e ete eens feet eees 242
Structtre i. ssc cnceanecccaea ry eee es Rudid Plaheaa te HK AGEs ONas SarteRa NS 242
ABO cece ee cece een nen nnn enn EET tenet tt ete ece 243
Correlation of Paleozoics .. 0.2... seer cece ee cette nent e een nees ve cae 248
Mesozoies:. ..cvvccvec cect cd Heawow reek seer seo NG EEE Ce eee da eener eves 244
Corwin series (Jura-Cretaceous) . 01... see e sect cere ese terete rnc ee enes 244
Character and occurrence .......-.e cee ee nee ee er eetne eens teneee D44,
Structure... cee cet ence eee eee n eee ee eee eee tenet ete Fees 244
AGC cece reece ee etree Fenner ene ete EE Fe teens 244
* Published by permission of the Director of the U.S. Geological Survey.
XXXV—Bors. Gron. Soc, Am., Vor. 13, 1901 (233)
2384 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Page
Anaktoovuk series (Lower Cretaceous).........0065 cece cece reece ee neee 245
Character and occurrence......----+seee eee cece teen eee teenies 245
Structures: <2 ste-we accent heed oie idee gland Satan Oe teak Bee 245
AGCiaws ck pene eeqeerags kets, ELL stayin teareri CAs, “Oe Raie eamina dans eae at 245
Koyukuk series (Lower Cretaceous)....-- 2-062. .: eee e cere ere eee een e nee 246
Character and occurrence....... 6. cee eee cee eee eee een cee eeeee 246
StRIGEOTS oo 5065. ceaescds BRE Ce Eae ds eeNEeeE thee es Season nae 246
HiBe cau (tipid debadata maces set aeA ce Aaee ee SON aancnate cae a 246
Bergman series (Cretaceous?)... 1-206. cee eee eee e eee ene eens 246
Character and OCCUrrENCE... 1.1 kee ccc ee eee etree eee einen 246
Stractulie osiwat osteoma eaten ope oekds wa eee eee 247
ARE bc Gide cree ba eee ewe Gene ee ete eee tenes Ene wnene ene es 247
Nanushuk series (Upper Cretaceous) ......--.0e cece eee terete eee seve BAZ
Character and OCCUITENCE.. 1... cece ee eee eee er eet eects 247
ABCbisisae ened ade ae nee oe EVES TE ES DEE Lowe (aa ey dea DY bs 248
Upper Cretaceous on the Koynkuk............. es oL oe Ns RAR RESET SE Tt 248
Tertiary—Colville series..........200 0s eee ee eee eee josde Spee sa teedeye tes 248
PlGIStOCEHG weiss Gee dedie ade ase Aedaguedaltenssidlote ale seh d8easeme ase 249
The deposits ...... 0... cece eee ee reece eee eens Rien thas Raia doa ano ZAD
GOODICSANGB: +0452 nes davks ousesenee rey Getasesseeeew nese een eb te 249
Glacial material. .... .. oa pid eles, See Gaeivie gh, SALMA ele aleleeaieiin nade es 250
Ground ice, marsh, muck, mud flats, etcetera...........0..04- ded Unend aber 251
GEOGRAPHY AND TopoGRAPHY
IN GENERAL
The section lies in the hitherto unexplored part of northern Alaska.
It extends from the 66th parallel north latitude roughly along the 152d
meridian by way of the Koyukuk, John, Anaktoovuk, and Colville rivers,
a distance of nearly 400 miles, to the Arctic coast.*
Geographically the region traversed by the section comprises three
distinct provinces, that of the Koyukuk or southern, the mountain or
middle, and the Arctic slope or northern.
KOYUKUK PROVINCE
This province, extending from the 66th parallel more than 100 miles
northeastward to the southern base of the mountains, lies mainly in the
northwestern part of the large Koyukuk bagin.t The province in gen-
* For a fuller account of this region the reader is referred to the Preliminary Report on a Re-
connaissance in Northern Alaskaalong the 152d Meridian to the Arctic Coast, soon to be published
by the U. 8. Geological Survey.
+ For a more complete description of the Koyukuk basin the reader is referred to ‘‘ Preliminary
report on a reconnaissance along the Chandlar and Koyukuk rivers, in Alaska, in 1899." Twenty-
first Ann, Rep. U.8. Geol. Survey, part 2, p. 467. See also ‘‘ Bulletin of the American Geographical
Society,” vol. 34, No. 1, February, 1902: “‘ Recent work of the U.S, Geological Survey in Alaska,"
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KOYUKUK AND MOUNTAIN PROVINCES 235
eral consists of a rolling country composed essentially of Mesozoic rocks
whose low, rounded hills and ridges vary from 1,000 to 3,000 feet in ele-
vation. It is supposed to represent the Koyukuk portion of the Yukon
plateau, but which here is not distinctly marked. The drainage, which
is separated from that of the Arctic slope by the Endicott mountains,
is southwestward. The master stream is the Koyukuk, which flows into
the Yukon, while the large tributaries are South Fork, John, Alatna,
and Alashuk rivers. The lower part of all these tributaries, as well as
the Koyukuk, meanders in wide valley flats, bordered by the rolling
country which has been noted. The Koyukuk river is navigable by
steamboats to Bettles, near the 67th parallel, a distance of about 530
miles above its confluence with the Yukon.
MOUNTAIN PROVINCE
The middle or mountain province is the most striking. It consists of
a rugged range of mountains composed of Paleozoic rocks extending
east and west across the field between latitudes 67° 10’ and 68° 25’.
These mountains, for which the name Endicott is locally proposed, here
have a minimum width of 80 miles and an average elevation of 6,000
feet. Orographically the range is regarded as the northwestward con-
tinuation of the Rocky Mountain system of the United States and British
Columbia, which here trends nearly east and west entirely across northern
Alaska, forming the great Transalaskan watershed between the Yukon
on the south and the drainages of the Arctic ocean on the north.
In their northward and finally westward course they form a promi-
nent feature of the concentric geography of Alaska, and embrace in the
concavity which they present on the south the great basin of the Yukon
and its well known but not always distinct feature; the Yukon plateau.
West of the 153d meridian, in the region of the head of the Colville and
the Noatak rivers, the mountains decrease in elevation and seem to
divide or fork, forming two ranges. The northern range, continuing
westward, terminates in the low mountains and abrupt sea cliffs of cape
Lisburne at Bering sea, while the southern forms the divide between the
Noatak and the Kobuk rivers.
On the southern side the rise from the rolling Koyukuk country is by
means of foothills, but rapid. On the north the mountains bréak off
somewhat abruptly, much as they do along the edge of the Great plains
in the western United States, as shown in plate 41. Pronounced fault-
ing and uplift are evidenced by marked deformation of the strata and
the presence of fault scarps, sometimes recognizable for miles. Where
they were crossed the mountains locally present a crescentic or concave
front to the northward, which is followed by low concentric ridges in the
plateau beyond, though these grow weaker and die out farther northward.
936 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Where best observed during the past season, principally on the John
and Anaktoovuk rivers, a view across the top of the range presents the
general appearance of a deeply dissected plateau or baselevel plain,
which has probably been uplifted from near sealevel, and whose former
surface is denoted by the expanse of closely crowded peaks, which in
general rise to an elevation of 6,000 feet, forming an even sky line, as
shown in plate 42. The floors of the mountain valleys lie,at about 2,000
feet, and the open pass near the northern edge of the range between the
John and the Anaktoovuk rivers lies at an elevation of scarcely 2,500
feet. For this dissected plateau feature at the top of the range the name
Endicott plateau is proposed.
It.seems not improbable that, as our knowledge of the physical geog-
raphy of Alaska becomes more complete, it may be found that the
Endicott plateau, having probably a considerable extension to the east-
ward, may be correlated with similar features, namely, the Chugatch
plateau, representing the westward continuation of the Saint Elias range
in southern Alaska, whose dissected surface also lies at an elevation of
about 6,000 feet.*
The drainage of this portion of the range is principally southward
into the Koyukuk. The master stream is the John river, rising near
the northern edge of the range. The main drainage ways are therefore
of a transverse character, extending across the strike and trend of the
rocks as well as across the trend of the range, while the tributaries of
these larger streanis, being nearly always controlled by structure, flow
in general along the strike to enter the master streams, producing a
rectangular system of drainage. John River valley may be characterized
in general as open, though certain sections are canyonous, because of the
character and structure of the rocks. Benching or remnants of old val-
ley floors occur at heights respectively of 1,700, 600, and 100 feet above
the present stream, and seem to mark stages of comparative rest in the
progress of orographic uplift of the land mass from a former lower level.
Northward sloping benches at the head of John river denote that a large
area of the drainage at the head of this stream, now flowing southward
into the Koyukuk, formerly drained northward and entered the Arctic
ocean through the Anaktoovuk and the Colville instead of Bering sea
through the Koyukuk and the Yukon, as at present.
COLVILLE OR ARCTIC SLOPE PROVINCE
This northern geographic province extends from the northern base of
the mountains, in latitude 68° 25’, northward to the Arctic coast, a dis-
*The geology and mineral resources of a portion of the Copper River district, Alaska. U.S.
Geological Survey, Washington, 1901,
BULL. GEOL. SOC. AM. VOL. 13, 1901, Pl. 42
ENDICOTT PLATEAU AND ENDICOTT MOUNTAINS CARVED FROM IT
COLVILLE OR ARCTIC SLOPE PROVINCE 237
tance of 160 miles. It consists primarily of two distinct features, a very
gently rolling plains country, for which is proposed the name Anaktoovuk
plateau, and a nearly flat tundra country or coastal plain. The inland
edge of the Anaktoovuk plateau, which is composed of Cretaceous rocks,
has an elevation of 2,500 feet, and with gentle slope extends northward
for a distance of 80 miles to latitude 69° 25’, where, at an elevation of
800 feet, it is succeded by the nearly flat Tertiary coastal plain, which,
with very gentle slope, extends 80 miles farther northward to the Arctic
coast. The drainage of this province is almost directly northward into
the Arctic ocean. The master stream is the Colville, whose headwaters,
so far as known,seem to make a somewhat wide detour to the westward
before flowing directly to the sea. The next larger stream is the Anak-
toovuk, which, rising in the mountains just east of the head of John
river, flows northward through the southern part of the province and
into the Colville. The most prominent features of the plateau are a few
low, transverse ridges, extending across it from east to west, feebly imitat-
ing the front of the mountain range and the shallow valleys that carry
off the drainage. ?
The coastal plain, which is underlain by Tertiary beds, has a breadth
of about 80 miles. It descends with very gentle slope from an elevation
of 800 feet in the interior to near sealevel at the coast. In its inland
portion, the Colville river has sunk its bed to a depth of 200 feet below
the surface of the plain, but the interstream areas are flat, with the sur-
face, which appears to be fresh-constructional in form, dotted here and
there by extremely shallow ponds and lakelets, which in most instances
are without outlet and present no suggestion of progress toward the de-
velopment of any system of drainage.
GEOLOGICAL SECTION
The horizontal scale of the section (plate 40) is 10 miles perinch. In
order to show the structure in the Tertiary coastal plain and represent the
flats and delta near sealevel at the north, it has been given a vertical ex-
aggeration of 5:1. As the section is confined to the line of traverse, in
order to represent more accurately the relations of the rocks as actually
observed, it deviates somewhat from a straight line in its extent across
the field from A to J. Owing to this restriction to the line of traverse
in the valleys where the relief has been relatively reduced by erosion,
especially in the mountainous portions, the profile rarely rises to the
normal height of the top of the Endicott plateau; consequently this
plateau feature of the range is not represented by the profile of the sec-
tion. Atthe northern base of the mountains, where the profile descend-
ing from the mountains, passes from the upturned Devonian on to Plies-
238 =F. GC. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
tocene till, which is soon found resting on Lower Cretaceous, a belt of
several miles has been left blank. It is thought possible that Carbonif-
erous and Lower Mesozoic strata may occur in this region between the
Devonian and the Lower Cretaceous.
The rocks encountered comprise representatives of most of the geo-
logic formations from Silurian to Recent. In point of distribution, as
shown in the section, they consist primarily of a belt of Paleozoics 80 to
100 or more miles in width, constituting the Endicott mountains, against
whose slopes, unconformably on either side, rest the edges of the plateaus
or uplands, composed of Mesozoics, which in turn are succeeded by Ter-
tiary. Beginning with the oldest, these several formations or rock series
will be briefly noted. As the field is new, the names here employed to
designate the various formations or series are proposed provisionally.
To afford a more comprehensive view of the relations of the several
series and avoid repetition in referring to them individually, it may be
well to note at the outset some features of structure which are common
to nearly all the Paleozoic series and apply to the range as a whole,
namely, that the series all strike or trend approximately east and west,
parallel with the trend of the range. They are nearly all traversed by
the dominant jointing or major structure of the range, cutting the rocks
in a northeast and southwest direction, with dip nearly vertical or
steeply northwest, at an angle of 75 to 80 degrees. This dip may be
considered normal, since the uplilt of the land mass of the range to the
east exceeds that on the west. The series also nearly always exhibit
one or more sets of secondary jointing or minor structure, trending in a
general northwest or southeast direction, approximately at right angles
to the major structure. The above statements of structure pertaining
to the Paleozoics in the range apply also in a limited way to the adja-
cent Mesozoics on either side.
We may also note that, with the exception of the greenstone schists
occurring in the Totsen series. the Paleozoics of the range, as well as the
younger formations of the Arctic slope, are all sedimentary and, so far
as observed, free from igneous intrusions of any kind.
The Endicott range consists of two somewhat distinct geologic axes,
of which the southern seems to be composed of the oldest rocks, namely,
the Skajit formation, and the Totsen series, of which the former is the
most prominent.
PaLrozorcs
SKAJIT FORMATION (UPPER SILURIAN)
Character and oecurrence.—The rocks of, the Skajit formation consist of
heavy-bedded limestone and mica-schist. The limestone is highly al-
SKAJIT FORMATION AND TOTSEN SERIES 239
tered, being finely crystalline, schistose, and often micaceous. Some
layers, becoming more and more foliated, grade into mica-schist. The
series occurs in the southern part of the Endicott mountains, where its
breadth or exposure in a north and south direction is 15 or 20 miles.
Here it rises toa height of more than 5,500 feet, forms some of the
highest and most rugged topography of the southern axis, and seems to
have a thickness of at least 4,000 feet.
Structure.—So far as known, the formation has a general east and wegt
strike, parallel with the trend of the mountains. The middle portion is
synclinal, while the northern and southern edges are anticlinal. The
formation is unconformable with the Fickett series of the north and ap-
parently so with the Totsen series on the south. both of which it seems
to underlie. In general the dips are gentle, but in some localities fault-
ing and folding has been intense. The rocks are cut by the major and
minor jointings of the range, with the joint planes sometimes locally fol-
lowed by veins of calcite and quartz, containing occasionally a little
galena or pyrites of iron and copper.
Age.—Though the limestone, as noted, is much altered by metamor-
phism, it contains imperfect faunal remains, one of which has been
identified by Mr Charles Schuchert as probably Meristina or Meristella,
referring the formation provisionally to upper Silurian and placing it
among the oldest known fossil-bearing rocks of northern Alaska and the
northern part of North America.
TOTSEN SERIES (SILURIAN)
Character and occurrence.—This series of rocks,-including a strip of
greenstone schist, occupies an east and west belt 12 miles in width.
It occurs to the south of the Skajit formation, which it seems to uncon-
formably overlie, while it unconformably underlies the Bergman series
on the south. The rocks consist mainly of mica-schist and some quartz
mica-schist, in both of which the essential minerals are biotite and quartz.
Locally the rock becomes graphitic and in cases carries considerable
quartz in small veins and lenticular bodies, some of which may be the
source of the placer gold colors found in the gravels. The series is essen-
tially of sedimentary origin, but the period of sedimentation seems to
have been accompanied by igneous effusives or flows of basaltic character,
which were later sheared and schisted with the sedimentary beds, giving
rise to greenstone schist, of which the most prominent belt, having a
width of several miles, occurs in the southern part of the field. Though
on account of deformation and folding there is probably some duplica-
tion in the Totsen series, its total thickness, by conservative estimate, is
probably 6,000 or 7,000 feet.
240 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Structure.—The Totsen series, like the other rocks composing the range,
trends approximately east and west, and though asa whole the series
has been intensely folded, the dip in general is monoclinal, being south-
ward at an angle of 60 degrees. The major and minor jointings of the
range are pronounced. Cleavage was noted at several localities.
Age.—Though the Skajit formation and the Totsen series have un-
doubtedly been folded and crushed together, judging from the apparent
higher degree of metamorphism in the Totsen series we should infer that
it may prove to be the older, notwithstanding, it seems to overlie the
southern edge of the Skajit formation. It is provisionally referred to the
Upper Silurian with the Skajit series.
STUVER SERIES (PRE-DEVONIAN)
Character and occurrence.—The Stuver series is the oldest group of rocks
exposed in the northern axis of the Endicott range, of which they form
the core. This is on the east and west line of the most pronounced and
geologically most recent crustal disturbance. The uplift, which seems
to have been going on since middle or late Paleozoic time, has taken the
form of a broad anticline whose longer limb extends to the southward,
while the shorter forms in part the north front of the range. Elevation
was accompanied by faulting; the movement or thrust came from the
south, and along the axis of the anticline has produced an over thrust
fold or fan structure. On the north, faulting has resulted in the break-
ing of the strata and the formation of a fault scarp in the north limb of
the anticline, between the north edge of the Stuver series and the Lis-
burne formation. This was farther accompanied and followed by fault-
ing and erosion, which broke up the immediate region into several great
fault blocks, and finally brought the Stuver series into view along the
bight of the fold. From the north edge of the range pronounced faulting
extends southward into the range for a distance of 15 or 20 miles. The
Stuver series consists primarily of hard flinty conglomerate and quartzite,
with some slate and shale.
Structure—The exposure is limited to a narrow belt about 5 miles
in width, trending northward for an unknown distance from the Anak-
toovuk valley between the faulted and eroded edges of the Lisburne
formation on either side. On the south, by uplift and faulting, it has
probably been brought into contact with the lower Carboniferous of the
Fickett series. Both here and at the north edge of the series, the fault-
ing, as shown in the section, seems to be normal, but in the Stuver series
the major jointing trends about east and west and the minor nearly
north and south. The series is cut by a well marked cleavage, dipping
northwest at an angle of 45 degrees. The undisturbed relation of the
Stuver series to the Lisburne formation is apparently conformable. If
any unconformity exists, it must be very slight,
STUVER SERIES AND LISBURNE FORMATION 241
No estimate can be formed of the thickness of the Stuver series, as its
lower limits are unknown. The exposed portion amounts to approx-
imately 2,000 feet.
Age.—From its position below the the Lisburne series, which is con-
sidered to extend to below the middle Devonian,.the Stuver series can
certainly not be younger than lower Devonian, and is regarded probably
pre-Devonian, to which it is provisionally referred.
LISBURNE FORMATION (DEVONIAN)
Character and occurrence—The Lisburne formation consists of medium-
bedded limestones, with some shale. It occurs next above the Stuver
series, and. like the latter, has been greatly disturbed by crustal move-
ments. It forms a belt 15 or more miles in width, extending east and
west across the valley of the Anaktoovuk. On the southwest it is soon
delimited by the fault scarp of Contact creek, and farther westward by
the Carboniferous of the Fickett series, with which its relations are not
definitely known. To the eastward of the Anaktoovuk the belt seems
to widen. The series is probably in contact with the Carboniferous on
the south, while in descending the slope of the mountains on the north
it disappears beneath the mantle of glacial till, where, judging from
topography, it is probably soon met and overlain by the Mesozoic or
‘Lower Cretaceous. From what has been observed in the region of the
Anaktoovuk, the thickness of the formation is probably a little over
8,000 feet.
Structure.—The entire area of the Lisburne formation here considered
is more or less deeply involved in the system of faulted and disturbed
blocks referred to under the Stuver series. At the north base of the
mountains west of the Anaktoovuk, the formation disappears beneath
the covering of glacial drift with a dip of 60 degrees to the north, while
east of the Anaktoovuk, a couple of miles distant, it similarly disap-
pears, but with a dip to the south at an angle of 75 degrees against the
fault scarp of the Stuver series, as shown in the section, plate 40.
Age.—On the basis of Devonian fossils found in surface fragments near
the top of the mountains formed by the Lisburne formation, the latter
is provisionally referred to the Devonian.
The Upper Devonian fossils thus collected by the writer have been
identified by Mr Schuchert as follows:
Zaphrentis. Rhombopora.
Aulocophyllum. Eridotrypa near or identical with E.
Diphyphyllum. barrandei (Nicholson).
Fenestella. Productella two species.
Unitrypa Spirifer disjunctus.
Hemitrypa. Platyostomu,
XXXVI—Rur. Gron. Soc, Am, Vor, 13, 1901
242 ¥F. C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Fossils were also found in place, but these are too highly altered and
crushed for identification.
FICKETT SERIES (LOWER CARBONIFEROUS)
Character and occurrence.—The Fickett series comprises rocks of very
diverse character, ranging from chloritic schists or phyllites on the south,
through limestone, slate and sandstone, quartzite, and grit, to hard con-
glomerate on the north. As shown in the section, figure 1, the series,
roughly speaking, lies essentially in the broad trough between the two
axes of the range already described. This trough was probably occu-
pied by a shallow arm of the sea in late Paleozoic time, when the axis
on the north and the south stood above sealevel, and from which
sediments of the Fickett series have probably been in part derived. The
series has a width or north and south extent of about 50 miles. On the
south its edges rest unconformably on the Skajit formation of the
southern axis, as shown in the geological section, while on the north,
owing to the faulting, as noted at the head of the John and Anaktoovuk
Tivers, its relations to the older rocks of the northern axis are not defi-
nitely revealed. It seems, however, to meet the Stuver series and Lis-
burne formation by fault contact, as has been indicated in the section.
To the north of this contact, so far as observed in the region of the
Anaktoovuk, all trace of this series in place, though it must have been
of considerable thickness, seems to have been removed by deformation
and erosion. To the westward, however, beyond the limits of the fault-
block system of the Devonian, at about 20 miles from the Anaktoovuk,
the Fickett series, as already noted, seems to overlie the Lisburne for-
mation and possibly extends beneath the Mesozoic at the north base of
the range,
Structure.—The Fickett series, like the other Paleozoics of the range,
has been subjected to faulting and folding incident to the mountain-
building forces. The folding in some localities has been intense, as is
shown by closely appressed anticlinal folds, and puckering in the schist.
The structure, however, broadly speaking, is essentially monoclinal,
with strike and trend east and west and the dip south at an angle of
about 45 degrees, pointing strongly to a later and also to a greater ele-
vation along the northern axis than along the southern. The major
structure of the range is exhibited throughout the region covered by the
Fickett series. ‘There are many faults whose planes are usually slicken-
sided and dip 70 to 80 degrees northwest. ‘The minor jointing is also
present. The schists, and notably the phyllites, often exhibit excellent
cleavage, with medium north to northwest dips.
FICKETT SERIES 248
Age.—On the basis of Lower Carboniferous fossils found in the stream
gravels, and the lithologic resemblance of the fossil-bearing gravels to
the rocks contained in the series, and the relation of the series to the
limestone formation, which seems to be Devonian and to underlie it, the
Fickett series is provisionally assigned to Lower Carboniferous; but as
the fossils are believed to occur near the base of the series, it probably
contains also rocks younger than the Lower Carboniferous.
The following are the principal forms collected by the writer and
identified by Mr Schuchert:
Lithostrotion. Pinnatopora.
Cystodictya nearest to C. lineata. Productus scabriculus Martin.
Streblotrypa near nicklesi Vine. Productus semireticulatus Martin.
Rhombopora. Spirifer striatus Martin.
Fenestella. Spirifer near S. neglectus Hall.
Fenesteila near F. cestricensis Ulrich Spiriferina cristata Schlotheim
Mr Schuchert states that—
“The above localities represent one formation, in the upper portion of the
Lower Carboniferous. This fauna, however, is unlike that of the Mississippi val-
ley, in that if does not have such characterizing fossils as the screw-like bryozoan
Archimedes and the blastoid genus Pentremites.
“he only other Alaskan region with which this Arctic Lower Carboniferous
fauna can be compared is that found on Kuiu island, in southeastern Alaska.”
CORRELATION OF PALEOZOIC
As lack of space forbids the correlation of each individual formation
or series, especially of those of the Paleozoics, with similar formations of
the same age in other parts of Alaska or the Arctic regions, it may here
be briefly stated that the present season’s work, together with the evi-
dence previously collected to the eastward and that to the westfvard in
the Cape Lisburne region, seems to indicate beyond question the exten-
sion of a well developed belt of Paleozoic formations across northern
Alaska, along the Rocky mountains, from the 35th meridian near the
Mackenzie to the 66th meridian at cape Lisburne, a distance of nearly
1,000 miles. In the Cape Lisburne region, as noted, these rocks, having
a known width of 75 or more miles, terminate in abrupt sea cliffs. The
thickness of the section here is not known, but it must be considerable,
from which it seems safe to infer that as a submarine geologic axis the
Paleozoics probably extend far seaward, and, as this part of the ocean is
known in the main to be shallow, it is not unlikely that the same Paleo-
zoic axis may continue across and reappear to the westward on the
Siberian coast. It may be noted, however, that on the portions of this
244 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
foreign coast visited by Doctor Dall he reports the rock to be essentially
crystalline or igneous.
Mrsozorcs
CORWIN SERIES (JURA-CRETACEOUS)*
Character and occurrence.—The Corwin series is not represented in the
section, nor is it known to extend go.far eastward as the Anaktoovuk.
It was encountered several hundred miles northwest of this on the
coast near Wainright inlet, whence it extends southwestward a dis-
tance of 180 miles to near cape Lisburne, where it plays a very impor-
tant part in the geological section of that locality, and since the topog-
raphy and the open, uniform character of the intervening country sug-
gests a probable great extension of the series to the eastward, and its
geological horizon is known on fossil evidence to be above the Fickett
and below the Anaktoovuk, to be next described, it seems not unlikely
that the Corwin series occupying this horizon may extend far inland
along the north slope of the range to near, if not beyond, the meridian
of the section. The series consists of medium to heavy bedded impure
gray and brown sandstone and arkose, with shale, shaly slate, and coal.
The coal includes the Wainright, Beaufort, ‘hetis, and Corwin coals, to
which the names Cape Lisburne coals and Cape Beaufort Coal Measures
have also been collectively applied, and which are likely to prove of
economic value. While the northwestern edge of the series forms the
coast line, the southern edge seems to rest unconformably on the Paleo-
zoics on the south.
Structure—The beds lie nearly horizontal or dip southwest at an angle
of 80 to 40 degrees, are slightly folded and faulted, and are traversed by
two set# of jointings, one approximately parallel with the strike and the
other approximately at right angles to it, agreeing in a general way with
the major and minor structures in the inland portion of the range, as
has been noted.
Age.—Fossil plants found in the Cape Beaufort region, and more par-
ticularly in the shale near the Thetis mine, at cape Sabine, by Mr Dumars
and Mr Woolfe and others, have been identified by Professor Fontaine
and Doctor Ward as not older than the Oolitic nor younger than the
Lower Cretaceous, but as probably on a line between the two.t
On this evidence, together with forms collected by the writer from
* It is possiblo that the rocks at cape Beaufort may on further research prove to be older than
Jura-Cretaceous, but for the present it seems best to include them in the Corwin scries,
+A full description of these collections will appear in Doctor Ward’s second paper on the Older
Mesozoic floras to be published by the U, 8, Geological Survey.
CORWIN AND ANAKTOOVUK SERIES 245
near Wainright inlet, the Beaufort series is provisionally assigned to the
Jura-Cretaceous. :
The forms from near Wainright inlet are as follows:
Nageiopsis longifolia Font. Older Potomac of Virginia (Lower Cretaceous).
Podozamites distantinervis Font. Older Potoniac of Virginia (Lower Cretaceous)-
Baiera gracilis (Bean) Bunbury. Oolitic of Yorkshire, England (Jurassic).
ANAKTOOVUK SERIES (LOWER CRETACEOUS)
Character and occurrence—The Anaktoovuk series, named from the
river on which it occurs, forms the southern or principal part of the
gently rolling Anaktoovuk plateau along the north side of the Endicott
range, which it meets at an elevation of about 2,500 feet, as shown in
plate 41. Here its inland edge seems to rest unconformably on the
Devonian limestone of the Lisburne formation, from whence the series
extends northward a distance of about 60 miles, where it unconformably
meets and underlies the Nanushuk series. Eastward the Anaktoovuk
series is probably soon limited by the front of the Paleozoic range, while
to the westward and northward it probably embraces and constitutes
the so-called Meade River mountains, and, continuing northwestward,
may extend to the Arctic coast. The series consists essentially of heavy-
bedded impure, dark-gray, or dirty-greenish, fine or medium grained
sandstone. An inspection of their mineral constituents shows that the
sediments are obviously derived from the Paleozoic rocks of the range,
and especially from the Stuver series.
Structure.—The strike or trend of the Anaktoovuk series is approxi-
mately east and west, with the prevailing dip generally north, so that,
broadly considered, the structure is in the main monoclinal. Follow-
ing deposition, the beds were gradually uplifted and thrown into gentle
anticlinal and synclinal folds, probably in sympathy with the later
of the mountain-building forces that were exerted in the range to the
south. Two systems of jointing frequently traverse the rocks. Of these,
what seems to be the dominant or major system trends northwest
and southeast, with dip steeply southward at an angle of 80 degrees,
while the secondary or minor traverses the rocks at nearly right angles
to the major, with dip 80 degrees southeast, both systems agreeing in
general trend with those of the Paleozoics in the range to the south.
Age.—The series is determined on fossil evidence to be Lower Creta-
ceous, constituting the typical Aucella beds of Alaska. Remains were
collected at 8 miles north of the foot of the mountains and successively at
other points in crossing the series. Of these forms, the principal or most
characteristic, as determined by Doctor Stanton, are Aucella crassocollis
246 ¥. C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Keyserling, or a closely related form and undoubtedly of Lower Cre-
taceous age. The series is to be correlated with the Koyukuk series, to
be next described, though the lithologic difference between the two series
is somewhat marked.
KOYUKUK SERIES (LOWER CRETACEOUS)
Character and occurrence.—The Koyukuk series constitutes the southern
45 miles of the section lying principally between the 66th parallel and
the Arctic circle, on the Koyukuk river. The series, however, is known
to extend much farther southwestward, and may with further discovery
prove to have a very wide extent over the Koyukuk basin. The rocks
of the series consist of impure pink and reddish limestone, dark shale,
slate, and some sandstone or arkose, all more or less associated with or
intruded by igneous rocks, denoting volcanic activity during and subse-
quent to Lower Cretaceous time. The series is represented as limited
on the northeast by the Bergman series, which in a general way it seems
to underlie, but may later be found to be closely connected with it in
point of geologic ‘age. Owing to the various breaks in the sequence of
outcrops, and the changed attitude of the rocks, no estimate of the thick-
ness of the Koyukuk series can be given as yet. It may be noted. how-
ever, that at the point where the fossils were collected, near the southern
end of the section, the limestone alone exhibits a thickness of about 800
feet. :
Structure—The series has been variously disturbed by folding and
some faulting, but the prevailing dip seems to be northward, roughly
speaking, at an angle of 40 degrees. A profuse jointing trends nearly
north 25 degrees west and dips steeply northeast, while a well marked
cleavage dips 75 degrees southeast.
Age.—The age of the Koyukuk series is supposed to be the same as
that of the Anaktoovuk series, Lower Cretaceous. This assignment. is
based on the evidence of fossils collected in the impure Hmestone near
the southern end of the section, and which were found to be undoubtedly
of Lower Cretaceous age by the presence of Aucella crassicollis Keyserling,
thus correlating the Koyukuk series with the Anaktoovuk series, both
containing Aucella beds typical of Lower Cretaceous in Alaska.
BERGMAN SERIES (CRETACEO vf )
t
Character and occurrence.—The series consists of a comparatively uni-
form group of rocks, covering a large area in the Koyukuk basin and
forming in large part the rolling Koyukuk upland already noted. It
succeeds the Koyukuk series on the north, and has a north and south
BERGMAN AND NANUSHUK SERIES 247
extent of about 60 or 70 miles. On the north it rests unconformably on
the schists of the Totsen series at the base of the mountains, while on
the south it is apparently infolded with the Koyukuk series, which it
is supposed to closely succeed in geologic age. The series consists essen-
tially of thin-bedded or medium-bedded impure gray or brownish sand-
stones and dark slates, with some dark shale and occasional conglom-
erates ; but along the north it is bordered by a belt of conglomerate from
several to 10 miles in width, which apparently represents the basal
member of the series. The series is undoubtedly of sedimentary origin,
but the sediments have been largely derived from igneous rocks, as
shown by the generally feldspathic constituents of the sandstone and
by the presence of basaltic or diabasic and granitic pebbles in the con-
glomerate on the Alatna river and at Lookout mountain. The sup-
posed basal conglomerate on the north is, however, composed essentially
of limestone and mica-schist materials derived from the Skajit formation
and the Totsen series. An accurate estimate of the thickness of the
series cannot be given. From a general impression, however, it seems
safe to indicate that it will probably amount to 2,000 feet.
Structure—The series has been considerably folded and somewhat
faulted, but to a much less degree than the Koyukuk series. A pro-
nounced jointing trends northwest and southeast and dips 80 degrees
northeast. A minor jointing trends north and south and dips east at
an angle of 80 degrees. On the north, where the series apparently rests
against the Totsen series, the dip is about 45 degrees south.
Age.—No fossils beyond undeterminable lignitic plant remains have
thus far been found in the Bergman series. From its apparent close
relations, however, to the Koyukuk series it seems that the Bergman
series is probably Cretaceous. Lithologically it bears a strong resem-
blance to the Anaktoovuk series to the north of the range.
NANUSHUK SERIES (UPPER CRETACEOUS)
Character and occurrence—On the north, the Nanushuk series succeeds
and seems to unconformably overlie the Anaktoovuk series, while north-
ward it disappears beneath the Tertiary rocks of the coastal plain, with
which its relations are also apparently unconformable. Its width in a
north and south direction is about 30 miles, while its east and west dis-
tribution is probably somewhat similar to that of the Anaktoovuk series.
The rocks are mainly thin bedded gray and brown sandstone, generally
fine grained and sometimes friable, slate-colored arenaceous and impure
fossiliferous limestone, dark shale or mud rock, soft uncleaved slate,
fine grained gray quartzite, drab-colored chert, and bituminous coal.
248 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
Where best observed on the Anaktoovuk, the beds strike nearly east and
west and dip south at an angle of 80 degrees, but the prevailing dip of
the series, however, is probably north. The series has been somewhat
folded and slightly faulted, and it is cut by a pronounced system of joint-
ing or sheeting along planes approximately horizontal.
Age.—On fossil evidence, the series is assigned to the Upper Cretaceous
by Doctor Stanton, who has identified the following forms :
Inoceramus, a large species. Tellina, two species.
Astarte, numerous. Siliqua.
Nucula, numerous specimens. Modiola.
Avicula. Scaphites.
Pectiunculus, several specimens. Hammonia.
Thracia.
UPPER CRETACEOUS ON THE KOYUKUK
To the south of the Endicott range and south of the limits of the
section in the Koyukuk region, Upper Cretaceous has also been found.
Of the collection made here by the writer, Doctor Stanton reports the
following forms and refers the beds to about the same horizon as the
early Chico:
Ostrea. Lucina.
Anomya. Trigonia cf. T. leena Gabb.
Mytilus. Corbula. :
Pectunculus cf. P. veatchit Gabb. Actxonella ef. A. ovifornis Gabb.
Opir ?
TERTIARY—COLVILLE SERIES
This series of Tertiary terranes succeeds the Upper Cretaceous or
Nanushuk series on the north, forming a flat tundra country or coastal
plane. It extends from some distance above the mouth of the Anak-
toovuk 100 miles northeastward to the Arctic coast. The inland edge
of’ the coastal plain has an elevation of about 800 feet, from which, with
very gradual slope, the surface descends approximately to sealevel at the
coast. The series consists principally of heavy bedded, partially con-
solidated silts or mud rock, with intercalated harder layers of soft sand-
stone, limestone, shale, lignite, and unconsolidated silts (see plate 48).
The sediments are conspicuously derived from the preceding Cretaceous
formations and the Paleozoics of the Endicott range. So far as observed
during the past season, the series is separable into two parts—Oligocene
and Pliocene. The portion assigned to the Oligocene is best exposed
along the Colville in the region of the mouth of the Anaktoovuk. Here
VOL. 13, 1901, PL. 43
BULL. GEOL. SOC. AM.
COLVILLE RIVER AND BLUFFS
COLVILLE SERIES 249
.
it constitutes the lower three-fourths, or 150 feet, of the section exposed,
and includes ‘all the above noted rocks, excepting the unconsolidated
silts. These latter are free from lignitic remains, and on the basis of
their invertebrate fossils are assigned to the Pliocene. Accordingly the
Pliocene, so far as observed, gonsists of nearly horizontal stratified beds
of mostly tine gray slate,and ash-colored calcareous silts, containing
faunal remains. By conservative estimate the thickness of the Colville
series is probably 500 or 600 feet, and, judging from topography, it prob-
ably has a very great extent in an east and west direction, possibly reach-
ing the coast in the region south of point Barrow.
Though the series, as shown in plate 48, has been slightly faulted, °
folded, and crowded from the inland direction, it is on the whole but
little disturbed. The beds lie nearly horizontal or dip gently north or
northwestward at a low angle of 4 or 5 degrees, as shown in plate 43.
The lower part of the series is supposed to be Oligocene on the ground
of the presence of the lignite beds and vegetable remains it contains and
its resemblance to known similar beds occurring elsewhere in Alaska,
and also on the ground of its relation to the Pliocene silts which it im-
mediately underlies. Lignitic shale examined by Doctor Dall is sup-
posed to contain the form of Sequoia lungsdorfi Heer. The upper part
of the series is assigned to the Pliocene on the basis of its fos8il forms,
which have been reported by Doctor Dall as follows :
Chrysodomus, 2 species. Macoma incongrua von Martens.
Amauropsis. Astarte semisulcata Leach (possibly
Tachyrhynchus polaris Beck. Quaternary intrusion).
Macoma frigida Hanley. Saxicava arctica L.
PLEISTOCENE
THE DEPOSITS
Besides the present stream gravels, the most important Pleistocene
deposits traversed by the section, but not represented on it by reason of
the small scale, are the Goobic sands, glacial deposits, ground ice, and
muck.
GOOBIC SANDS
This formation is a surficial deposit of brownish sand or loam about
10 or 15 feet in thickness, which, like a continuous mantle, overlies the
beds of the Colville series unconformably, as shown in plate 43 at the top
of the bluff just above the light-colored triangular exposures of Pliocene.
It seems to be distinct from the Colville series and to be persistent over
XXXVII—Burn. Gron. Soc. Am., Vor. 13, 1901
250 F.C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
a wide area of country. It not only forms the surficial terrane of the
coastal plain along the Colville, but seems to be persistent along the coast
from the mouth of the Colville westward, while its inland margin seems
to overlap onto the Upper Cretaceous of the Nanushuk series. In char-
acter, the material composing the deposit is fine-grained and, on the
whole, uniform or homogeneous. Its description as fine sand, with an
admixture of considerable silts or earthy material, perhaps best conveys
an idea of the texture of the deposit. In some localities it seems to be
more distinctly sandy toward the base and earthy toward the top, where
it sometimes grades into from one to several feet of dark-brown or black
humus or muck, clothed at the surface with moss and a little grass.
The deposit is ordinarily free from gravel, but in several instances peb-
bles ranging from mere grains to as large as one-fourth of an inch in
diameter were found. These consist essentially of dark flint and may
be characterized as subangular. They are sometimes roughened or
grooved, as if wind-worn. They occur very scatteringly indeed. It
should be noted, however, that in some instances a very fine gravel or
grit occasionally intervenes between the base of the deposit and the
underlying Tertiary beds.
The deposit, as a rule, is structureless or devoid of stratification. In
only a féw instances were indications of stratification observed, and this,
though it was faint and indefinite, seemed to dip at a considerable angle
and was accompanied by indistinct crossbedding. Weathered faces of
the deposit frequently present the appearance of unpronounced stratifi-
cation ; but on careful removal or cutting away of this weathered part,
in search of more conclusive evidence, the material is found to be struc-
tureless. Owing to its surficial and widespread occurrence, the homo-
geneity of its materials and its structureless character, and the difficulty
of explaining its origin, for want of a better term in field-work the de-
posit was called loess. After further consideration, however, it is feared
that the retention of the term would be undesirable, for which reason
the deposit is here given the name of Goobic sands.
To account for the origin of the Goobic sands, the following causes
have suggested themselves, namely, glacial, fluviatile, delta, eolian,
marine or beach, none of which alone seems to afford a satisfactory ex-
planation. It is probable, however, that the fluviatile delta theory, in
conjunction with shallow coastal conditions and intense Arctic freezing,
may prove the most tenable.
GLACIAL MATERIAL
; . bor tinea da
While there is no evidence ofAtealp+recional glaciation in northern
Alaska, it is now known that ice action has been far more extensive than
PLEISTOCENE DEPOSITS 251
has been generally supposed by geologists who have drawn their deduc-
tions concerning this remote region from observations made on a trip
down the Yukon or along the western coast. The Endicott mountains,
as illustrated in the topography shown in plate 42, do not seem, so far
as observed, to. have been overridden by an ice-sheet, but in the valleys
nearly everywhere there is such evidence of ice drainage as strise, ter-
minal moraines, and deposits of till. The breeding ground for these
glaciers was in the Endicott range, with the zone of maximum accumu-
lation probably somewhat north of its median line. Here the mountains
were doubtless largely overlain by an ice cap or névé, but the ice move-
ment was confined essentially to the drainageways leading off to the
north and to the south. But on the north slope of the range the ice
seems to have moved off, at least locally, in a continuous sheet or small
regional glacier, with its front reaching north beyond Willow creek, some
35 or 40 miles beyond the base of the mountains. This is evidenced by
the more or less continuous till sheet overspreading the entire region
and by deposits of drift and erratics on the highest portion of the Cre-
taceous plateau. In the valleys this sheet or ground moraine attains a
thickness of about 150 feet. From the edge of the ice-sheet ice drainage
in the form of valley glaciers continued about 40 miles farther north-
ward, to near the mouth of the Anaktoovuk, but none crossed the Col-
ville, whose drainageway does not seem to have been interrupted since
the Tertiary. Aw.
On the south_#f the Koyukuk basin similar, but not so pronounced,
evidence extends to beyond the Arctic circle, a distance of 50 or more
miles southward from thé base of the range. Here, however, the gla-
cial phenomena, so far as observed, are more of the valley glacier type,
but the deposits are undoubtedly till and contain striated pebbles of
distinctly glacial type. Along the route of traverse, omitting the mound-
like remnant, about 3800 feet in diameter and 60 feet in height, near the
middle of the range in John River valley, the glacial ice has disappeared
from the country.
GROUND ICE, MARSH, MUCK, MUD FLATS, ETCETERA
The northern 30 miles of the section, pet the point where the
Tertiary bluffs of the Colville series leave the river, lie in marsh flats
whose inland half is continuous with the ground abandoned by the Col-
ville river in its lateral migration or drifting of 30 or more miles west-
ward and its simultaneous down-cutting into the Tertiary terranes,
while the coastal half lies in the Colville delta, both of which features,
however, slope down to low marshes, and finally expansive tidal mud
252 =F. C. SCHRADER—GEOLOGICAL SECTION IN NORTHERN ALASKA
flats and bars at the coast. Inland, these abandoned flats are probably
underlain, in part at least, by the lower beds of the Colville series; but
where their edges form the banks of the river at 10 to 20 miles from the
coast they seem to be composed of dark muck and ground ice for a
depth of 10 or 15 feet below the surface.
DEEP SEA EXPLORATIONS
BY
C. H. TOWNSEND
DIRECTOR OF NEW YORK AQUARIUM
Printed by permission from
THE NEW INTERNATIONAL ENCYCLOPAEDIA
PuBLISHED BY Dopp, Mrap anp Co.
Coprricat, 1902, sy Dopp, Mreap anp Co.
DEEP-SEA EXPLORATION
1. U.S.S, ALBATROSS dredging, 8. SURFACE NETTING.
2. THE OREDGE AND ITS RIGGING. 4. TANGLES,
5. INTERMEDIATE SELF-CLOSING TOW-NET.
DEED.
deeds being required only to convey the class
of interests known as incorporeal, such as ease-
ments, profits, future interests in land, and the
like. : But deeds have now, under the technical
description of grants, almost entirely superseded
other modes of conveyance of interests in land.
Only estates for years or tenancies at will are
still capable of arising by parol or by writing
not under seal, and in England even leaseholds,
for three years and upward, can be created or
transferred only by deed. In Great Britain and
most of the United States, the general use of
deeds for purposes of conveyance is a matter of
regulation by statute.
In form, however, the deed remains substan-
tially the same as at common law. The writing
must still be on paper or parchment, though it
may to-day be done by the typewriting machine
or the printing-press. The old requirement of a
seal is also generally adhered to, though in a
few of the Western States it has been abolished,
and in most others a scroll, or similar mark
made with the pen, may be substituted for the
more usual wafer or sealing-wax. But, whatever
its form, the important thing is not the adhesion
to the paper of something called a seal, but the
sealing of the instrument by the party to be
bound by it. It must be ‘his own act and seal.’
At the present time, also, it is generally con-
sidered that the instrument must contain the
name of the maker in his own handwriting, al-
though prior to the Statute of Frauds, in 1648,
signing was not necessary to the validity of
deeds, and it is not clear that the statute con-
templated any addition to the formalities with
which they were already surrounded.
Delivery is properly accomplished by the obli-
gated party handing over the sealed writing in
person to the party to be benefited thereby.
Either party may, however, be represented by an
agent, and a delivery to an unauthorized third
person is good if subsequently ratified by the
benefited party. Indeed, it has been held that
any unequivocal act on the part of the obligated
party, showing an intention to vest the posses-
sion of the document in the benefited party, is
sufficient to constitute a delivery, even without
a manual transfer of possession to any one—as
where the former, at or after the time of sealing,
utters the words, ‘I deliver this as my act and
deed,’ or where he incloses the sealed writing in
an envelope, addressed to the benefited party,
though retaining it in his own possession. There
is some cogflict of authority, however, as to
whether a delivery of the latter sort, or to a
third person, which, in fact, never comes to the ,
knowledge of the party intended to be benefit
will be sustained by the courts.
be a conditional delivery, which is m:
third person, as an ‘escrow,’ or mey@ writing,
to be delivered over to the benefited party on
the performance of some act or the happening of
some event. An escrow does not take effect as a
deed until the delivery over, when it takes effect,
by relation back, as of the time of its first de-
livery. See Escrow, and the titles of the vari-
cus kinds of deeds. as Covenant; Grant; Liase
AND RELEASE. Consult: Coke on Littleton;
Blackstone, Commentaries on the Laws of Eng-
land; Kent, Commentaries on American Law;
Pollock and Maitland, History of English Law
(2d ed., London and Boston, 1899) ; Holmes,
740
DEEP-SEA EXPLORATION.
The Common Law (Boston, 1881); and the au-
thorities referred to under REAL Property.
DEEMS, Cuartes Force (1820-93). An
American clergyman. Te was born in Baltimore,
graduated at Dickinson College in 1839, and was
for some time agent in North Carolina for the
American Bible Society. He was professor of logic
and rhetoric in the University of North Carolina
from 1842 to 1845, and held the chair of natural
sciences in Randolph Macon College (Ashland,
Va.) from 1845 to 1846. He then became a
Methodist preacher at New Berne, and for five
years was principal of the Greensboro Female
College. In 1865 he went to New York, where he
helped found the Church of the Stranger (unde-
nominational), of which he became pastor. In
1881 he founded the American Institute of Chris-
tian Philosophy. Among his many publications
are: Life of Dr. Adam Clarke (1840) ; The Home
Altar (1850); Annals of Southern Methodism
(1856) ; Life of Jesus (1872); A Scotch Verdict
in Evolution (1886); The Light of the Nations
(1886) ; The Gospel of Common Sense as Con-
tained in the Canonical Epistle of James (1889) ;
Chips and Chunks for Every Fireside; and
Wit, Wisdom, and Pathos (1890); The Gospel of
Spiritual Insight, and Studies in the Gospel of
John (1891). Consult his Autobiography (New
York, 1897).
DEEM’STER, Dempster, or Doomster (AS.
dom, doom, judgment, as in Domesday Book;
hence doomster or deemster, a judge). The
name of an officer formerly attached to the High
Court of Justiciary in Scotland, who pronounced
the doom or sentence of condemned persons. The
office was held along with that of executioner. At
the conclusion of a trial, this dread official was
produced in open court, in presence of the
wretched criminal, as is graphically described by
Scott in his tale of Old Mortality. See notes to
that work, and also notes to Heart of Mid-
Lothian. The office of deemster has been long
abolished. In the Isle of Man and Jersey deem-
sters are judges, the office as well as the title be-
ing of great antiquity and dignity. The highest
judicial authority in the Isle of Man is divided
between two deemsters, one for the northern and
the other for the southern half of the island.
DEEP RIVER. A river rising in Guilford
County, N. C. (Map: North Carolina, C 2). It
flows southeast and then east, and, joining the
Haw River (q.v.) in Chatham County, forms the
Cape Fear River (q.v.). About 120 miles long,
the stream drains an area of 1350 square miles.
Extensive coal and copper deposits are found in
its valley. It furnishes extensive water-power
-at Lockville, and is navigable to Carbonton.
DEEP-SEA EXPLORATION. The depths
of the sea have been explored with precision only
during comparatively recent years. Deep-sea
investigations began in the necessity for accurate
soundings for submarine cables, and this is still
the main reason for sounding, but much more has
been accomplished in this field by dredging for
purely scientific purposes.
The most important part of our knowledge of
deep-sea conditions has been gained since 1870.
The Challenger expedition sent out by the British
Government from 1873 to 1876 (see CHALLEN-
GER) engaged in pelagic investigations for nearly
four years, sounding and dredging in the oceanie
basins at more than 350 different places. This
cr
DEEP-SEA EXPLORATION. 7
vessel was well equipped, and carried a scientific
staff under the direction of Sir Wyville Thomson.
A great amount of deep-sea work was accom-
plished, and the large series of Reports form the
most important contribution ever made to the lit-
erature of this subject. Other extensive deep-sea
investigations have been conducted at various
times by most of the European governments,
while vessels of the United States Coast Survey,
or of the Fish Commission, have been engaged
in them more or less regularly since 1870. The
Prince of Monaco has made very important con-
tributions to this department of knowledge, as he
has for many years employed his yachts almost
entirely in deep-sea work, and has devoted much
time to the improvement of the appliances for
investigation.
The methods employed by the earlier investiga-
tors for measuring the depths were slow and un-
certain, for their soundings were made with hemp
rope, which was greatly drifted by currents and
gave inaccurate depths. The soundings and
dredgings conducted on the Challenger were so
made, and often under great difficulties. At the
present time such investigations are made by
means of wire, the first successful employment of
which was by Sir William Thomson in 1872.
Wire sinks rapidly, presents the least frictional
surface, and is but little affected by currents;
and the machinery is now so perfect that sound-
ings may be made with accuracy in the greatest
depths. The improved methods show that the
early soundings by the Herald, Congress, and
other vessels with rope, supposed to have reached
over 7000 fathoms, were erroneous, and that
there are probably no such depths in the ocean.
The greatest depth known was discovered by
the United States cable-survey ship Nero in 1900,
near the island of Guam, where a sounding was
made of 5269 fathoms, or nearly six statute miles,
a depth sufficient to submerge the highest moun-
tains. It is probable that future soundings will
reveal slightly greater depths. For four years
prior to the voyage of the Nero the deepest water
known was north of New Zealand, where the
British ship Penguin sounded in 5155 fathoms.
Off the coast of Japan, in 1874, the United States
ship Tuscarora found a depth of 4655 fathoms;
and in 1900 the United States Fish. Commission
steamship Albatross made a sounding in the
western Pacific of 4813 fathoms. Many great
depths have been discovered in the Atlantic, the
deepest (4561 fathoms) off Porto Rico, by the
United States Coast Survey steamer Blake. More
than forty ‘deeps,’ or depressions ranging from
3000 to 5200 fathoms, are now known, some of
them mere holes, others of vast extent. The
deeps are well distributed over the seas, but
none have been found north of the fifty-fifth
degree of latitude. The average depth of the sea
is probably not less than 2200 fathoms.
Meruop or Sounpine. In the operation of
sounding several instruments are sent down with
the wire. A thermometer takes the temperature
at the bottom; a closing cylinder brings up a
specimen of the bottom water for analysis, and
the sounding cylinder at the end of the line
brings up a specimen of the bottom mud or ooze,
for examination as to the character of the bot-
tom. These instruments are all self-acting at
the bottom and are not affected in rising to the
surface.
To the sounding cylinder is attached the sinker
41 DEEP-SEA EXPLORATION.
—a 60-pound iron shot—which detaches itself on
striking the bottom. An indicator attached to
the reel on deck shows the number of fathoms of
wire that have run out. After sounding the wire
is reeled in by steam. It takes about one hour to
make a sounding three miles deep and get the
instruments back on board.
Deep-Sea Drepeine. The methods employed
on board the United States Fish Commission
steamship Albatross, doubtless the best-equipped
deep-sea dredger in existence, may be taken as
illustrative. The Albatross has brought together
larger deep-sea collections than have been made
on any other vessel. She has made nearly 6000
hydrographic soundings, and nearly 2000 hauls
of the dredge or beam trawl. The investigations
of this vessel cover areas extending from the
Banks of Newfoundland along both coasts of
North and South America to Bering Sea, and also
limited areas in the tropical Pacific, and in the
regions between Japan and Kamchatka. Her
work has carried dredging into deeper waters
than ever before, animal life having been obtained
near the Tonga Islands at a depth of 4173 fath-
oms, while the dredge on one occasion in Bering
Sea brought up from a depth of 1771 fathoms
more than 800 deep-sea fishes at a single haul.
The creatures of the deep sea are brought up
by means of a dredge or beam trawl towed by a
wire rope, operated by a powerful engine on deck.
The first operation in dredging is to ascertain
the depth by sounding, after which the trawl is
put overboard and allowed to sink to the bottom
as the dredge rope is let out. The dredge, or beam
trawl, is simply an iron frame to which is at-
tached a strong bag-shaped net about 20 feet
long. The mouth of the dredge, as formed by the
iron frame, is about eleven feet wide and two
feet high. Dragged along the bottom, it quickly
fills with animals. Sometimes it settles into
mud or ooze and is very hard to lift. The dredge
rope is connected with a large spring, or accu-
mulator, attached to the foremast, which often
shows the dredge to be pulling thousands of
pounds. Before the dredge reaches the surface,
most of the cozy mud washes away, so that the
dredge haul is usually light enough to be hoisted
from the water and landed on deck with safety.
Sometimes it is filled with fishes; sometimes
with sea-urchins, starfishes, crinoids or corals:
sometimes with squids and devil-fish. It often
brings up a varied collection, in which many
classes of marine animals are represented. The
time required by the Albatross in gmaking her
deepest dredge haul—that from 4175 fathoms—
was ten hours, the engine reeling in the great
weight of line very slowly. In depths of 1000 to
1500 fathoms hauls can be made in three or four
hours, according to conditions.
In addition to the dredge, another collecting
machine, very useful on rough bottom, is the
‘tangle.’ This consists of bunches of shredded
rope attached to iron bars, and when dragged
over the bottom it frequently brings up sea-
urchins, starfish, and crinoids in abundance. A
deep-sea fish-trap has been devised by the Prince
of Monaco, in which fishes have been taken as
deep as two miles. The Albatross, in 1897, suc-
ceeded in setting ordinary gill-nets a mile deep,
and catching Macrurus and other deep-water
fishes. Decp-water exploration by means of gill-
nets, traps, and trawl lines promises to yield
interesting results,
DEEP-SEA EXPLORATION.
Deep-Sea Lire. The surface of the sea nearly
everywhere bears an abundance of minute animal
and plant life. In this surface life, or ‘plankton,’
as it is called collectively, many groups of inver-
tebrates are represented. The phosphorescence
often seen upon the surface of the sea is due en-
tirely to their presence. These almost micro-
scopic creatures are constantly dying and falling
to the bottom. They constitute the principal
food of the smaller animals dwelling there, and
their remains form a large part of the deep-sea
oozes. The most important forms among them,
considered with reference to abysmal deposits, are
the Globigerinide and the radiolarians, which
are enormously abundant.
The marine deposits on the ocean floor are gen-
erally referred to three groups: Those of the con-
tinental slopes are called Terrigenous Deposits,
derived from the land through the wearing ac-
tion of rivers, tides, and currents. These coast-
wise deposits are the blue, green, coral, or vol-
canic muds, and are characteristic of the adja-
cent land slopes from which they are derived.
Farther off shore, generally about 200 miles, oc-
eur the Pelagic Deposits, made up of dead ma-
rine organisms from the surface—the minute sur-
face life already referred to. Here we find oozes,
such as diatom, radiolarian, or globigerina oozes
which depend respectively upon the character of
the surface life prevailing above them. Beyond
these, in the deeper parts of the ocean, are the
Red Clay Deposits, which cover about half the
ocean floor. This region is not affected by matter
from the land, and receives little pelagic matter
from the surface. It lies so deep that the shells
of surface organisms falling down are removed
through the solvent action of the deep water.
The red clay is believed to have formed very
slowly, not more than a few feet of matter hav-
ing accumulated since the Tertiary period.
INTERMEDIATE DEPTHS. The question as to the
existence of life at intermediate depths has been
given general reconsideration since the perfecting
of closing tow-nets for the exploration of such
depths. The experience gained with the various
intermediate nets used on board the Albatross
has shown no mingling of surface and bottom
forms. The latter occur, of course, at all depths
along the Continental slopes. See DrsrTRrBvu-
TION OF ANIMALS.
From the evidence now at hand with respect to
light in the sea, it seems certain that the sun-
light does not extend below a couple of hundred
fathoms, and even there becomes very dim. Be-
low this the vast body of the ocean is absolutely
dark, being illuminated only where phosphores-
cent creatures may shed a certain amount of
steady or intermittent radiance (see below).
Conprtions aND Lire at Great Deprus. It is
always cold at the bottom of the sea, the influence
of the warm surface waters not extending below
a few hundred feet. In the great depths the
temperature is always close to the freezing-point.
In warm equatorial seas, where the depths ex-
ceed 400 fathoms the difference between surface
and bottom temperatures usually ranges from 40°
to 49° F. It has been found that from 100
fathoms down, or throughout the waters beyond
the influence of the sun, temperatures remain
practically constant. At the surface of the sea
the lines of equal temperatures are parallel with
the equator, although subject to deflections by
currents, while at the bottom they follow the
742
DEEP-SEA EXPLORATION.
general trend of the continents. The cold water
of the depths comes from regions far to the north
and south of the tropics, the coldness being due
to the water in polar or subpolar regions sinking
and gradually spreading itself over the ocean
floor. If for any reason the cold polar waters
should cease to flow downward toward the deep
tropical basins, the deep-sea water would rise in
temperature, and deep-sea life would perish from
lack of the air which the polar currents absorb
at the surface and carry down with them. So far
as is known, the bottom currents are extremely
slow, and, as the water is not affected by storms,
it is likely that the lower part of the deep sea is
a place of calm repose.
There is a tremendous pressure of water in the
depths; so great, in fact, that it will crush all ob-
jects that are not constructed to resist it. All
deep-sea instruments are made to withstand a
pressure increasing about a ton to the square
inch with each 1000 fathoms of depth. At the
greatest depth known there would, therefore, bea
pressure of nearly six tons to each square inch of
surface. The tissues of deep-sea animals are so
permeated by fluids, however, that a balance is
maintained, and at the bottom they may be as
firm as animals of the shallow waters. Most of
these creatures are so soft that when withdrawn
from the pressure which keeps them in a firm
condition at the bottom and brought to the sur-
face, they must be treated carefully to prevent
their going to pieces. The bones of abysmal
fishes are especially cartilaginous. When deep-
sea creatures are dragged to the surface from
deep water they are always dead, and doubtless
die during an early stage of their upward jour-
ney.
PHOSPHORESCENCE AND Coror. It has been men-
tioned that no light reaches the abyssal regions,
which are absolutely dark so far as sunlight is
concerned; hence plant life is unknown there,
and all the animals of the depths are carnivorous.
Deep-sea dredging, however, has brought up so
many phosphorescent animals that there can be
little doubt of considerable phosphorescent light
in the depths. The amount of such light given
_off at the surface is no measure of that produced
under normal conditions at the bottom. Phos-
phorescent organs take many forms in the depths,
and occur in both fishes and invertebrates.
The colors of deep-sea animals are usually as
brilliant as those of animals living under the
influence of light, although not so varied. The
reds, yellows, purples, and greens predominate,
and the colors, when they occur at all, are apt
to be in solid masses, in striking contrast, or the
whole animal is of a uniform brilliant coloration.
There is a conspicuous absence of blue. The
fishes, as a rule, are dark-colored, but many of
the crustaceans, holothurians, and starfish are
brilliant.
EXPLANATION OF PLATE.
1. Method and theory of deep-sea dredging, as practiced
on the U.S. 8. Albatross. 2. The deep-sea dredge and its _
derrick. 3. Gathering the surface life, by hand nets, and
by a towing net rigged to the port boom. 4. The tangles,
showing its rigging. 5. The Townsend intermediate net,
open and closed. Having been sunk to the depth desired,
it is towed for a time and then a sliding weight is allowed
to run down the line; striking the ring which holds upright
the iron arm hooked to the tow-rope, it dislodges the ring
and releases the arm, which falls, permitting a weight be-
neath it to slide down and pinch together the folding rim
of the netting bag, which may then be drawn up without
loss of contents.
DEEP-SEA EXPLORATION.
Some of the deep-sea animals are blind. Those
that have eyes probably capture their prey by
the phosphorescent light shed from their own
bodies and the bodies of the vast number of other
creatures that are constantly flashing their faint
lamps over the ocean floor. Fishes of the greatest
depths have the smallest eyes, while those of mod-
erate depths have very large eyes, as, for in-
stance, those of the Macrurus type. Many of
them have highly developed organs of touch.
Some of the fishes have enormous jaws, much
larger proportionately than are found among
shallow-water forms. Their teeth also are more
formidable. See Macrurus and Plate of CopFisH
AND ALLIES.
Sizz. All the animals that have so far been
brought up from deep water have been taken in
dredges of moderate size, so small, in fact, that
they are only capable of taking small animals,
the largest specimens of fishes seldom exceeding
four or five feet in length. It is quite possible
that by using larger dredges larger animals could
be taken.
ConcLusion and BisiiocrapHy. It will be
seen from the foregoing that the fauna of the
depths lives under such extraordinary conditions
as temperature close to the freezing-point, pres-
sure amounting to a ton to the square inch
for each 1000 fathoms of depth, and darkness
except for light due to phosphorescence.
Consult: Thomson, Depths of the Sea (London,
1873); Wild, Thalassa (London, 1874); Re-
ports and Narratives of the Challenger Expedi-
tion (see CHALLENGER ExpepITIOoN) ; A. Agassiz,
Three Cruises of the ‘Blake’ (Boston, 1888) ; an-
nual Reports, Bulletins, ete., of the United States
Fish Commission (Washington, 1872 onward) ;
Bulletins and Memoirs of the Museum of Com-
parative Zodlogy (Cambridge, 1875 onward) ;
Tanner, Deep-Sea Hxploration (Washington,
1897) ; Townsend, Records and Bibliography of
the ‘Albatross’ (Washington, 1901).
DEEP-SEA FLOUNDER. A name given lo-
cally in the North Atlantic States to both the
plaice and the pole-flounder (qq.v.).
DEEP-WATER SCUL/PIN. See Sea-Raven,
DEEP-WATER TROUT. See SQueTeacuE.
DEEP-WATER WHITING. See Wauittne.
~
co ties acne wild beast, animal, Ger-
Thier, a oth. dius, wild beast; cf. AS.
déor, bold, OHG. tiorlih, wild). The popular
name for even-toed, hoofed mammals of the fam-
ily Cervide and subfamily Cervine. The musk
(q.v.), usually called musk-deer, forms a dis-
tinct subfamily, which is sometimes accorded
full family rank. More than fifty species of deer
are known, occurring in all parts of the world
except Australia and southern Africa. South-
eastern Asia especially abounds with them, some
of the largest as well as many of the smallest
residing there. Only two species of deer dwell
in the whole continent of Africa, and both of
these are near relatives of European species and
occur only in the northern parts of the continent.
In North America there are perhaps eight or ten
species of deer, while Central and South America
possess u much larger number.
Deer are characterized by the absence of a gall-
bladder and the possession of upper canines, lat-
eral digits on both fore and hind feet, « remark-
able suborbital sinus or tear-pit below each eye,
743
_ ealled a ‘hart.’
DEER.
and antlers. Antlers are the most noticeable of
these characters, though they are usually present
only in the male. The female reindeer has ant-
lers and individual females of other species some-
times have small ones. Antlers (q.v.) are out-
growths of bone, which are covered with a thin,
highly vascular hairy skin during their growth,
but when this is completed the blood-supply is
cut off, and the skin, or ‘velvet,’ as it is called,
dries up and is peeled off, leaving the bone bare.
Antlers are renewed annually, the fully formed
pair becoming detached from the ‘pedicels’ on
which they were developed, and a new pair aris-
ing at the same place. Antlers are usually shed
soon after the close of the breeding season. An
antler may be straight and unbranched, but
usually there are branches, called tines or snags.
The number of these increases with age, so that
the most handsomely developed antlers are found
only on fully matured males. The antler and its
branches are generally more or less cylindrical or
terete, but in some cases they are very much
expanded and flattened, and the antler is then
called ‘palmated.’ .
Deer are animals of very graceful form, com-
bining compactness and strength with slenderness
of limb and fleetness. They have for many cen-
turies been renowned as objects of the chase, and
the flesh of many species is highly esteemed for
food, under the name ‘venison.’ The best-known
species, which may serve as an example of the
group, is the European red deer (Cervus
elaphus), the adult male of which is the ‘stag,’
and the female is the ‘hind.’ The former is some-
times nearly seven feet long and over four feet
in height, but the hind is much smaller. The
body is covered by a double coat of fine wool and
longer, coarse hairs, the latter longest on throat
and chest. The wool is brownish-gray, and as it
is longest and most abundant in winter, the sum-
mer coat is brighter-colored and smoother. The
young are spotted with white. The antlers are
at first unbranched and only show the number of
tines characteristic of the adult in the fifth year,
and it is not until then that the young male is
dignified with the name stag. An old stag is
The hinds and young stags are
usually found together in large herds, but the
older stags occur in smaller groups, while harts
are generally found alone. The feeding time is
during the evening and at night. The food varies
with the season; in winter it is chiefly lichens,
moss, bark, and buds, while in summer leaves and
herbs form most of the diet. Stags are said to
eat only fungi during the breeding season. The
red deer occurs in all parts of Europe and in
northern and western Asia, It is exterminated
as a wild animal in populous districts, but is
preserved as an object of the chase, or as a semi-
domesticated pet, in all parts of western Europe,
though not so common in Great Britain as the
fallow deer. It is exceptionally swift of foot and
an excellent swimmer, and all of the senses are
marvelously acute. The hinds and fawns are
gentle and can be tamed as pets, but the stags
are untrustworthy and become quite dangerous
during the breeding season.
The American deer (Cariacus or Odocoileus
Virginianus) is considerably smaller than the
stag, but resembles it in many of its habits, It is
found throughout the eastern United States,
ranging northward into southern Canada, west to
the Missouri, and south to Florida and Texas.
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