The Meridian times. (Meridian, Idaho) 1909-1938, 1912-03-22

some of you in your work; for. after
all, each Of your individual problems
must be solved by yourselves.
The amount of plant growth is de-
pendent in decided measure upon
the amount of moisture, within GER
tain limits. in the soil. The supplying
and maintaining of this moisture in
an amount which will bring the great.
est return is, then, our problem.
The water found in soils is of three
kinds:
1st. Free water or the water
found between the soil particles of a
saturated soil.
End. Capillary water or that which
Is held in thin film around each of
the soil particles of a moist but not
saturated soil. This is the water used
by the plant in its growth.
3rd. Microscopic water which is
the water held by the soil but which,
in all probability, is not used by the
plant
Only aqueous or water plants can
grow in soil containing free water.
Hence our problem is confined 10 the
regulation of the capillary water only,
and to the conditions which govern
plant growth. .....
There are three ways by which soil
moisture can escape:
LIST. BY sinking into deep soils out
of reach of the plant roots, anG escap-
ing by under drainage. ~. ,..
End. By eKaporating from the sur
face.
3rd. By passing through the plant
itself in a process known as trans
piration. aE "... .#.:.
Each of these losses can be gov
erned to a certain extent. The first
by making lighter applications OF
water at each irrigation. The second,
or surface evaporation, can be check
ed by cultivating the surface suff.
Gent to form dust mulch, thus clos.
ing up the opening of the capillary
tubes which form when the surface
soil begins to dry out. And the third
or Transportation can be checked by
the addition of soil fertility or by or
binary cultivation. Thus, the last two
can be governed by the simple opera.
ton of stirring the surface after an
irrigation.
The thought is prevalent among
farmers that a certain amount of
water must be used by plant in Or
der to produce certain weight of dry
matter. AS early as 1899 Woodward
found that it required less water to
produce a pound of dry matter in a
plant growing in a rich soil where the
plant food was evenly balanced, than
in one of opposite nature. Later, in
1878, German Investigator found
that the yield of dry matter was
greatest where Transportation was
least He also found that the enrich
ing of the soil enabled the plant to
produce dry matter with less water.
Now the question may arise in your
minds: Why should cultivation de-
crease the amount of water actually
used by the plant? Cultivation per-
mfts the air and sunshine to enter the
soil more readily, causing a conse-
quent liberation of plant food which
is equivalent in effect to the addition
of the food artificially.
That cultivation actually decreases
the amount of water used by the
plant is shown in the results of ex-
perfments conducted at the Utah ex-
pertinent station in the vegetation
house. Certain tanks were planted to
corn. An equal number of tanks con-
tanning the same kinds of soil were
left bare for a check on the eyapora-
ton from the surface. Forty eight
hours after each irrigation and then
every week, half the surfaces were
cultivated while the other half were
left bare. Table No. 1 shows the re-
suits.
TABLE NO. 1.