The record-union., 1899-09-04
Forests and
Rainfall.
By WINFIELD ]. Davis.l

and fertility Of the soil. The effect OF
the denudation of the forests OF Can-
fornia was a subject of scientlhc dls-
cussion as early as 1859 so far as re-
lated to climatology, though in desul-
tory way. In February, 1868, Or. l.
NJ Logan, a recognized authority on
meteorology, published a resume or the
rainfall at Sacramento for the period
from 1S49 to that date, and incidentally
touched on the subject of drouth and
its causes He said: The drouth, IN
consequence of the diminished rainfall
of 1864, caused the destruction of
from one-third to one-half of the cat
tie and sheep that ranged in the lower
valleys of the State. 1t has been sug-
gested in the annual report of our State
Board of Agriculture that seasons OF
drouth may be in a measure prevent
ed, or at least ameliorated, by a gen.
eral system of arboriculture.
I'm the present State of our knowl-
edge it cannot positively be affirmed
that the presence or absence of trees
affects the total annual quantity of
rain, though the balance of testimony
strongly favors the conclusion that
more rain falls in wooded than in open
countries. 1t is a well-established fact,
however, that forests, not only by
means of the moisture which they pro-
duce and condense, but likewise on ac-
count of the obstacles they impose on
evaporation from the soil, and by the
action Of their roots in rendering the
soil permeable, insure a permanency
and regularity of natural springs, and
this nT1lu Will hn IF1affc
the wood, but at some distance beyond
the borders.
LAS the forests are destroyed, the
springs which flowed from the woods,
and, consequently, the greater water
courses fed by them, diminish both in
number and in volume. This fact is so
familiar throughout the American
States and British provinces, that there
are few old residents in the interior of
those districts who are not able to
testify to its truth as a matter of per-
sonal observation"
The doctor quoted from Man and
Nature" a work on physical geography
that had been recently written by
George p. Marsh MY own recollec-
tion suggests to me many instances of
this sort, and / remember one case
where a small mountain stream, which
disappeared soon after the clearing of
the land where it rose, was recovered
about ten or twelve years ago by
simply allowing the bushes and young
trees to grow up on a rocky knoll, not
more than half an acre in extent, inn
mediately above it, and it has since
continued to flow uninterruptedly The
abounded in streams and rills, but in
many parts of those States which have
been cleared for above a generation OF
two, the hill pastures now suffer Sc
Verely from drouth, and dry seasons
no longer afford either water or herbage
for stock"
It is traditional that whole regions in
Spain which are now barren or nearly
so for pasturage a part of the season
were, before the noble woods were cut
down, free from drouth and rich in
crops. And the denuding Of that
country of it's trees has made the riv-
ers for the most part mere channels
for the winter rains. The Guadalquiver
which some poet called 'the mighty
river" enters the sea without water
enough to cover the loose black stems
that pave it's bed. The Holy Land now
often misses the latter rain" or re-
ceives it but sparingly and the brook
Kedron is but a low, dry ravine, pass
ing off to the eastward from Jerusalem
to descend between perpendicular walls
beside the monastery of Mar Saba to
the valley of the Jordan and the Dead
Sea.
In France the same tendency was
checked by legislation, which inter
fered, as early as 1863, to prevent the
Telling of forests without permission
This legislation became very stringent
early in the present century, and, in
addition, the Government exercised the
right of the compulsory planting OF
trees on the land of citizens who would
not plant voluntarily. The French law
of 1859 prevented the cutting down
of any wood larger than twenty-five
acres, unless it should appear to the
proper authorities that such wood was
not necessary to protect the soil on
mountain or steep slopes; or against the
.encroachment of rivers; or to preserve
springs and water courses from drying
up, or the sea shore from being blown
or washed away; or for the defense OF
the frontier or for the public health
1t was found in that country that tc
cut off the forests caused the hillsides
to be stripped Of soil, and the springs
to dry up; that torrents and freshets
were much more injurious afterward
and that the sea sand encroached upon
the arabic fields since the woods neal
the shore disappeared.
The effect of the laws against cut
ting and in favor of planting trees in
France was such that instead of q
land in the country. there was a con-
stant gain. In 1860 the wooded sur
face Of that country was S,7S3 "a:
hectares, or less than %, 10000 acres
the whole number of acres in France
then being at least 125, 100000. II
1865 the number Of hectares of woot
had increased to over 100000. OF
nearly q million acres more. In a few
of the other European countries the
preservation of wood has been under
taken, but nowhere with so much sue
cess as in France.
In 1867 NJ. Becquerel read a paper
on the subject before the French Acad-
emy, the first portion of which gave
details respecting the extent of for
est lands in France at various periods
the second discussed the climatic ac-
tion Of forests, and in it he stated that
their influence will be found TO de-
pend on their extent, on the nature oi
the trees, whether having deciduous OF
sar,F