The Caldwell tribune. [volume] (Caldwell, Idaho Territory [Idaho]) 1883-1928, 1912-01-05

to the different soils and crops in or,
der to make the greatest possible yieio
has always been serious problem to
all irrigators: 1t has always been
known that in order to secure the
biggest crop it is necessary to apply
different amounts to different crops
and to different soils with the same
crop, but just how much this amount
should be has never been known only
in an indefinite way.
The irrigation investigations de-
partment, which l represent in the
State of Idaho, has, in cooperation
with the state engineers oft1ce, Deen
carrying on series OF experiments
for the past two years by means OF
which it is hoped to determine this
very important factor, and We have
secured a vast amount OF data con-
corning it. These experiments have
all been carried out on comparatively
large areas and in practical way. >,
It does not give any indication OF
how much water. is necessary tor
maximum crop production on any
soil to merely measure the amount
that some farmer applies for the rea-
son that the same or larger crop
might have been produced with either
more or less water than that which
was really used, so we have been try.
ing to work out this feature by select
ing large number oft r acts on typl-
cal farms in different parts of Idaho
and then divide each tract into three
different parts ana apply different
amounts of water to each one. Water
was measured and varied in this man
ner on 90 different farms during l9lO
and on as many more during the past
season. Several factors in regard to
the use of water have been very
strongly emphasized, the principal
ones being that the amount of water
required depends upon: Q) The char
acter of the soil and sub-soil. The
texture of, the soil as regards poroslty.
has more to do with the amount OF
water used than any other one thing
and it has been found that adobe soils
may be irrigated with total appli-
cation of but or acre inches while
in some instances from l to Z acre feet
are required to spread over and thor
oughly irrigate an acre of very gravel
ly soil At least 20 of this latter
amount is almost invariably wasted
as it either passes into the ground
water or percolates beyond the reach
of the plant. roots. If coarse soil is
underlaid with an impervious stratum,
the amount of water necessary is ma
terially cut down, while if the imper-
vious stratum is lacking, some irriga-
ton system must be used which will
flood the ground quickly before the
water has time to penetrate too deep
ly if high duty is to be secured.
(2) Climatic Conditions.-The an
nual precipitation and. its seasonal
distribution, together with the temper
ature, humidity and wind movement,
all have very evident effect upon the
amount Of water required.
(3) Diversifcation of Farm Crops.
Where a farm is all devoted to one
crop such as grain, hay or potatoes,
the greatest need for water usually
falls within comparatively short
time, and there is but little u.s. for it
DURING the rest of the season. while
b.. diversifying his crops, the farmers
need for water will be more constant
and he is better able to make good
use of a continuous flow of the ditch
throughout the season.
~ Use of Rotation.-It is we'll
known to most irrigators that little
can be accomplished bv irrigating
with small heads of water, and much
larger and better use is secured from
the water where larger heads can be
used. Rotation systems, bv means of
which a farmer can exchange water
with his neighbor and use larger heads
for shorter periods, are now being
used with success in many localities
and the saving of water is very ma
terial. ps.. -.
(5) Preparation of the Land
Maximum crop production can not be
secured without uniform wetting of
the soil and this is impossible if the
land is not properly prepared and
leveled for irrigation. Rough, un-
even land, it is plain to see, requires
more water than smooth land, for it
has to be held on the land long
enough to soak up the high spots.
Careful preparation of the land is an
absolute necessity if the best use is to
be secured from the water.
(6) Kind of crop grown whether
cultivated or non-cultivated and
leHSIn Oh season tnat II needs water
have very direct bearing upon the
amount of water that will be required
by the crop. Spring ~rains, on ac-
count of their short season of growth
require considerably less water than
alfalfa which grows from early spring
until late fall. Winter grains, ali
other things being equal, require less
irrigation water than spring grains,
because of their ability to utilize more
OF the moisture deposited in the soil
from winter orecipitation. A crop
that can be, cultivated will need con-
slderably less water than non-cul-
tivated one because of the treat saw
ing that can be made by the reduction
OF the evaporation through cultiva-
ton. y.
1t is as easy to aonly too much wa
ter as it is to apply too little and
every bit as harmful. The expert
Iments carried on this year at Good
ing. show up the results of over-irri-
CATION very clearly We had 81 diff
ferent plots of wheat consisting of 3
varieties of plots each. These were
planted and handled in exactly the