Lincoln County times. (Jerome, Idaho) 1911-1919, 1911-11-09
COVER CROPS Benefit
where Irrigation Water Is
Abundant Alfalfa Is Grown.
Being Deep Roofing Leeume, It May
Be Of Advantage to Orchards
Where Moisture Is Plentiful
Some Objections.

successful irrigation is not condi-
TONED upon clean cultivation; in fact,
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. it 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-
rlgated valleys of Arizona cover
crop OF alfalfa reduces the soil tenn
perature, prevents the reflection of
neat which occurs from 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 II a 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 nse of fertilizers. and whether the
intercrop secured yields a profit upon
such investment is a calculation for
eign to this discussion. The purpose
/ simply Is TO emphasize the fact tha
on rich soil ample irrigation can pro
orchard. and 1t can do the same OF
a pastured orchard, but the heigh
and form of a cow-pruned fruit tire,
is totally abhorrent to present ideals
A cover crop and intercrop are
however somewhat different things
tween the rows of fruit trees is per
MISSILE II the land IS rich, and mois
ture. either by rainfall or by irriga
ton. is ample; but experience ha
shown that such a crop is only profit
able while the trees are very young
AS the trees expand they repress tn
growth OF the intercrop below tn
profit mark. and give no further II
ducement to the grower to longer er
danger the future Of his trees by d.
viding their sustenance with the intel
crop. On the other hand, a cove
crop. II 1t be legume, may re-enforc
the humus in the soil One Of tn
objections to continuous clean cultur
in the arid region is the tendency c
the soil to lose humus and to becom
lifeless and refractory. The growth {
clovers. peas, and other hardy legume
during the winter season. when tn
moisture is usually abundant. is bein
widely resorted TO for the purpose {
restoring humus. The summer growt
Of tender legumes with ample irrig
, ton is therefore. for this reason, a
I we'll as for lowering the soil temper
ture and escaping other effects of e.
= cessive temperature, worthy OF col
t siderauon II water is ample enoug
= to support the cover crop and II
trees.
Clearly where such practice is a
visable the irrigation method must
suitable If the land is nearly leve
j low check levees on contour lines wi
restrain sufficient water and not 4
, terfere with the use of the move
. Such contour checks may inclose
considerable number of trees. wit
greater slope the square check sy
TEN inclosing a single tree may
necessary. or dooding down Il
spaces between the trees, with a 10
levee along each row, may be II
most available system. except in sma
orchards. where pipe lines. hydrant
@ and sprinking may be used.-Farme
Bulletin No. 1l6.