Pullman herald. [volume] (Pullman, W.T. [Wash.]) 1888-1989, 1912-08-16
SOIL MOISTURE AND
CROP PRODUCTION
some Interesting Experiments Are
being Conducted at the State
College by Prof. G. Q. Thorn

ure to crop production.
Professor C. c. Thorn, who has
charge Of these experiments, believes
that when this problem is fully
understood the possibilities of crop
production throughout Eastern
Washington and all districts similar
VIII be increased from % to so per
cent.
Inc point of most interest In these
experiments Is the duty OF water. BY
this expression is meant the amount
OF water necessary to produce a
pound Of plant, whatever the plant
may be. In comparing the plants
| with each other, the crop is first re-
duced to dry matter by which Is
meant, a pound of crop material
from which all the moisture has
been taken out. This gives a more
uniform and absolutely just COMPARE
son as to the amount of water re-
| quired. Some interesting data in
this respect has already been OBJ
| tanned, and 1t Is found that there is
wide variation in the water re-
| quirements of the more common
crops. To produce one pound of
potatoes 1t takes 1877 pounds Of
water, while for wheat it takes 40
| nnnndG n VIZ fa
pound of dry matter. Here IS ex-
| pressed a wide variation, showing
the consequent necessity OF such
work, If the ag~iculturists and horti-
culturists of this portion of the state
are to choose the crops best adapted
to the drier sections. Accurate de-
Examinations have been made on
some IS different crops, the list Of
which is as follows:
Pounds of water produce one
pound of dry matter in each of the
following:
Potatoes, 1877; sorgum, $50;
onions, 235 corn, 200; barley, 294;
carrots, 297; beets (gugar), 304;
oats, 345 tomatoes $50; uabbage,
39S; sofa beans, 4OS; cmmer, AIS
bf ans, 444; wheat, 47O; peas, 519,
alfalfa, 800; clover. 600.
These results might be somewhat
misleading when we observe that
barley takes only 294 pounds Of
water to produce one pound of dry
matter, while wheat takes 40
pounds to produce one pound of dry
matter; yet it Is universally conced-
ed that wheat is a crop much better
adapted to the drier section than Is
barley. This result was somewhat
of a problem to the Investigators I'M
til it was learned by further expert
ment that when the barley plant
ceases to grow by being unable to
take up m ore moisture from the soil,
there is still left in the soil IL per
cent moisture, while there Is only
per cent moisture in the soil when
the wheat plant dies through lack of
moisture. This difference of per
cent, which comes during the latter
part of the season, and is the critical
period in crop production, enables
the wheat plant to keep on growing
and mature a crop, while the barley,
oats and other similar crops, being
unable to feed so closely, succumb
through their inability to take up
more moisture, thus in many, many
instances causing partial or complete
loss of crop.
1t has further been observed that
the richer the soil, the less moisture
it takes to produce pound of dry
matter for any of the given crops.
The analogy is somewhat similar to
feeding a calf upon skim-milk or
whole milk. The crop, which Is sup
piled with a richer soil solution can,
and does, get along with much less
moisture. This Is an exceedingly
important consideration to the one
same crop year after year, putting
little or no manurIal elements back
in the soil, thereby depicting the
food elements and rendering this
soil year after year more and more
less fit to produce crops, because OF
the continually increasing weakness
of the soil solution.
While these results have been OBJ
tanned in a small way, this year they
are being determined on one-tenth
acre plats on the Experiment Sta
ton farm, and the results of this, 1t
is almost safe to say, at this time,
will corroborate the work done pre-
viously, showing the practical nature
of this work and It's ultimate benefit
to agricultural practice.
Professor Thorn and his assistants
are busy preparing a considerable
exhibit of this work, and much other