Shoshone journal. [volume] (Shoshone, Idaho) 1884-1931, 1911-11-24
COVER CROPS BENEFIT
Where Irrigation Water Is
Abundant Alfalfa Is Grown.
Being Deep Roofing Legume, tt May
Be Of Advantage to Orchards
Where Moisture Is Plentiful
Some Objections.

Successful irrigation is not condI
toned upon clean cultivation; In fact
1t may be quite otherwise Cover
crops are sometimes of advantage
Recent practice in some parts where
Irrigation water is abundant beyond
the requirements of the tree, is to
grow alfalfa in the orchard. Being a
deep roofing legume. 1t may be of ad-
vantage to the trees In the presence
OF ample moisture, while with scant
moisture 1t would rob the trees and
practically ruin them In the hot ir-
rigated valleys of Arizona a cover
crop Of alfalfa reduces the soil tenn
perature, prevents the reflection of
heat which occurs from a light-colored
soil surface, and Is said to insure
thrifty young trees where clean cul-
ture destroys them. In cooler parts
OF the arid region, as in the mountain
valleys OF northeastern California and
in Idaho, alfalfa is also grown in
irrigated orchards. These facts are of
wide Significance as showing that irri-
cation may be found of benefit even
where clean culture may not be
thought desirable 1t is certainly rea-
sonable that If cover crop is grown
at all 1t should be attended by the
surety that the trees shall not suffer
for moisture, and they unquestionably
do sometimes suffer seriously under
old turf. even In lands of summer
rains.
This view is wholly apart from the
subject of exhaustion of soil fertility
by intercropping. OF course, compen-
sation for the depletion must be made
by use of fertilizers, and whether the
fntercrop secured yields a profit upon
such investment is a calculation for
eign to this discussion. The purpose
simply is to emphasize the fact that
on rich soil ample irrigation can pro-
duce good fruit on an intercepted
orchard, and 1t can do the same on
pastured orchard, but the height
and form of a cow-pruned fruit tree
is totally abhorrent to present ideals.
A cover crop and intercrop are,
however. somewhat different things.
The. growth of a cultivated crop be-
tween the rows of fruit trees is per-
If the land is rich, and mois-
ture, either by rainfall or by irriga-
ton, is ample; but experience has
shown that such a crop is only profit
able while the trees are very young
AS the trees expand they repress the |
growth of the intercrop below the |
profit mark. and give no further in |
ducement to the grower to longer en- |
danger the future of his trees by d. |
viding their sustenance with the inter-
crop. On the other hand, a cover
crop, If 1t be legume, may reinforce
the humus In the SOIL One of the
objections to continuous clean culture
IN the arid region is the tendency of
he soil to lose humus and to become /
ifeless and refractory. The growth of
,lovers. peas, and other hardy legumes
Turing the winter season, when the
moisture is usually abundant. is being
widely resorted to for the purpose of
estoriDg humus. The summer growth
If tender legumes with ample irriga-
ion is therefore, for this reason, as
veil as for lowering the soil tempera-
ure and escaping other effects of ex-
essive temperature, worthy of con-
liberation If water is ample enough
o support the cover crop and the
rees.
Clearly where such practice is adj
isable the irrigation method must be
uitable. If the land is nearly level,
DIV check levees on contour lines will
estrain sufficient water and not in
erfere with the use of the mower.
uch contour checks may inclose a
number of trees. With
reater slope the square check sys-
EN- inclosing a single tree may be
ecessary. or dooding down the
PAGES between the trees. with low
wee along each row. may be the
lost available system. except in small !
where pipe lines. hydrants.
nd sprinkling may be used.-Farmers
ulletin No. ZIG.