The farmer and mechanic. [volume] (Raleigh, N.C.) 18??-19??, 1911-07-18
USES OF WATER IN THE SOIL.
Methods OF Storing Water
III the Soil Have Increased Crop
Yields Greatly.
BY G.. W. SMITH.

pant SeLS the TODD supply
through the water in The plant. which
1t drinks in or absorbs from the soil
through the membranous surfaces of
the roots with their foot hairs. which
later greatly increase the surface
connection Of the plant with the water
of the soil
Large quantities of water thus taken
IN by the GIANTS are "breathed out
into the air through the leaves The
quantity OF water thus taken in and
given out by the plant is enormous
held crops consuming two hundred to
HVe hundred pounds of water for each
pound Of dry matter they add to
their W weight in growing.
The roots Of our field crops are
much longer, much more numerous
spread farther and penetrates into
the soil to greater depths than most
people realize. On the fairly open,
easily penetrated soils. where the up
per portion of the earth is often too
dry for the plant to feed. crops send
their deepest roots downward four to
six feet and in some cases much
deeper. The greater mt Of roots.
however, are in the upper eighteen
inches Of earth.
The richest portion of the soil and
the part in which the plant likes best
to feed, if sufficient water is present.
is the lower half or tWo-thirds of the
furrow slice. With greater depth the
plant obtains food with more diff
cuIty.
While the deepest roots doubtless
secure some food, their chief function
is to bring water from deep in the
earth when the supply near the sur
face is short. These long. deeply pene-
trating roots nave few branches near
the tip, while the branches are very
numerous near the surface. where the
,nntc rr~na] o,,t 600 o~ 20 ra,ol, tbA
more concentrated plant food from
every nook and corner Of the furrOW
slice and the uppermOst layer Of sub
soil. Only the outer recently de-
Eeloped ends of the root branches are
active in absorbing water and re
ceiving soluble plant food, the older
surfaces being covered with q tough
layer of barklike cells.
The roots of other cereal grains
are quite similar. and the roots Of
tame grasses penetrate to like depths.
The clOvers go a little deeper, while
some perennial field crops, like al
falfa, extend much deeper. But in
all cases the plants get more of their
food in the upper layers OF soil.
Since the furrow slice and the part
of the subsoil just below it are the
portions of the soil which supply the
most cOngenial and the richest pas
turage to the roots of crops, the ain
of the farmer should be to keep them
supplied with the proper amount OF
moisture and to provide that mechan~
zeal condition which best promotes the
growth and yield of the crops.
That a crop draws up through its
roots and allows to evapOrate. an I'M
menSe amount of water has been
clearly shown in all parts of the coun-
try.
Careful experiments IN America and
in Europe have shown that one
to two barrels of water 600 pounds
to 500 pounds are needed to prOduc
a pound of the dry matter Of many
of our common fields. If this amount
: is not available in the soil the crop
4 suffers, and if the supply is irregular
there is a lessened Yield.
: During wheat-groWing months Whe1
q the foliage presents the greatest ex
3 panse Of surface and the roots are
2 reaching several feet into the sol
5 for water there is a very great draf
7 of water.
: A conservative estimate would place
! the average moisture percentage II
the soil bearing a wheat crop ffteeI
per cent below that in the soil bear
: ing no cop.
8 1,y-v-vNr @-u~XXr ~ NOnnS