Wessington Springs herald. (Wessington Springs, Aurora County, Dakota [S.D.]) 1883-1891, 1886-03-12
SOIL MOISTURE.
Plant Economy In Dry Times, and ]
ventive Applications.

SOIL MOISTURE.
Plant-Economy In Dry Times, and Pro.
v~entive Applications.
A soil is made up of solid particles of
different sizes, ranging from pebbles
down to the finest dust; being irregular
in shape these particles do not anywhere
fit close together, like sardines in a box;
of course, however, all of them must
touch one another in many places, so
that those above are supported upon
those below, and those below can not
get from under their burden because
hedged in closely on all sides by their
neighbors, There are spaces around
these particles of solid matter, between
the many points where they touch one
another, which also vary much IN size
from such as are no wider than the
thickness Of goldleaf to such as are
large enough to thrust ones finger into.
These spaces are occupied by air or
by the other. If always filled with water,
the soil is no better than a bog; if al
ways filled with air, it is only Il barren
desert. Water that falls on the surface
of the soil and can find its way from one
to another of the larger spaces will run
down till it reaches the level of the
standing water in the ground; just as
water poured into a pipe in a we'll does
not stop till it reaches the level of the
standing water in the well. But water
that gets into the smaller places may be
held there, many feet above the level of
the standing wafer; rs if, having filled
the upper part of the well with sponges,
we should then pour water in, we know
| that much Of it, being taken up in the
very fine capillary tubes of the sponges,
will never reach the bottom; it will stay
in them till it dries out by evaporation
into tho air.
The best condition of the soil is
thought, by.those who have studied it's
relations to water and vegetation, to be
That in which not only all the spaces too
large to hold the water up contain moth
ing but air, but where a large part Of
the small spaces are also empty. Our
| upland crops do not thrive in soils so
situated that all these smaller spaces
near the surface are full of water. Veg
| citation is constantly taking up this
small Yosidue Of water that is lcft in the
soil after all the surplus VI a rain has
drained off and dissipating it into the
atmosphere; and when the supply OF
| water is not sufficient to meet this de-
mand, at least to a reasonable extent,
the plant willis, or, rs in the ease of In
dian corn, it's leaves curl up. How the
supply is replenished when the rains are
few and far between is a somewhat puz-
cling question. Too much credit is
| given to the power that the soil is sup
posed to have of absorbing moisture
from the atmosphere; the amount so abb
| sorbed is of small account except when
the air is very damp, which is not its
usual condition at such times when rain
is scarce. The power residing in tho
plant itself of reducing its consumption
of water is of much more account for
saving it from death by drouth than any
power which the soil has Of supplying
it with water by simple absorption from
the air. Some plants an, if necessary,
lower the rate at which they take up
water by their roots and give it off into
the air to one-tenth of the usual rate,
without showing, at least for a time,
any signs of suffering; and when the
! supply of water at the roots is moro
liberal they pump away again as fast as
ever.
Some substances added to the soil
check very much the rate of exhaustion
Of the water by negotiations; salt acts
thus, and plaster appears to be partios.
larly effe:tual. Thus the opinion con.
non am ong farmers may be accounted
for, that plaster lessons the danger OF
bad effects from IL scarcity Of water; they
say it tbsorbs water; but this is but Of
the question; all the ground plaster tina:
is sold has been exposed to the air for q
long time before the farmer buys it, and
it has had ample time and opportunity
to absorb all the moisture it can from
that source. But if it serves to lower
the rate of evaporation of the saltwater
into the air through the vegetation grow
ing on the soil, it is plain that it may TO
some extent serve the same purpose as
if it did actually absorb water from tho
air to be handed over to the plant crops
according to their needs; it husbands
the scanty stock of water in the soil. and
forces the plants to be more economical
in the use thereof. Some experiments
with salt have shown that the soil Of a
grass plot to which this substance had
been applied contained ten days after a
rain had fallen twice as much water as
did an adjoining plot which had received
no salt; and the plants on the former
plot were growing vigorously after
those on the other plot had begun to
show signs of su ffering for want of wa
ter.-Dr. G. c. CuldMeN, IN N. Y. Trio
me