Duncan Arizonian., 1911-11-01
WATER AND HARDPAN
First Care Is to Get Water Deep
Iy Into the Soil.
Rapid Evaporation From the Surface
Promptly Arrests the Downward
Seepage and the CapiIlarity Is
Then Upward.

The first care of the orchard irriga-
tor is to get water deeply into the soil
without flooding or pudding the sur
face. 1t is not after all so much mat
ter OF the number of inches used as
the deep diffusion of the water through
the soil to the full depth of the natural
roofing OF the tree. In this dry eli
mate, If the first two or three feet of
the soil are quickly saturated will
water, perhaps sufficient for six fee
CT healthy moisture, and then the III
cation is stopped, the rapid evapo
tion from the surface soil will prom
ly arrest the downward seepage al
the capillarity will be upward, sON
that none will go into the subsoil The
subsoil will then gradually dry out and
harden and each repetition of this op-
Grafton will aggrayate the subsoil con-
ditions until hardpan is formed into
which the water will not seep readily.
This results in the lower roots of the
tree being encased in hard, dry soil to
become inactive or even die, writes e.
]. Wickson in the Denver Field and
Farm
Another evil Of this condition is that
at each irrigation the air is driven out
of the upper soil so that the roots in
it are smothered, followed by such
evils as gum disease, die-back, paling
foliage and fruit dropping for we see
the tree unable to obtain sufficient
water to properly dilute the food elab-
t0H in hn fo = In,
proper solution for distribution
throughout the tree, and carry it to the
roots for the work of root extension
and mineral solution All attempts to
remedy this by the application of ma
nures and mulch to supply dissolvents,
or such delicately soluble salts as nj
trates to stimulate the solution, are
only temporarily beneficial and in the
long run bring on the greater compli-
cations.
Few irrigators k " much about
how water acts in the soil, as they
only see the surface and warrant the
criticism, of Wilcox in his Irrigation
Farming that "unskilled lkbor has a
penalty of twenty-five to fifty per cent !.
water and unfortunately this class is
too prevalent in the irrigating fields"
One of the mistakes often observable
on heavy soils is the running of five or
six burrows between each row of trees,
whereas three or four are sufficient.
The burrows should be no nearer than
sufficient to allow the water of each to
cif in M 70 IL
meet below. If streams are so close
that they mingle in their downward
course a foot cor two below the sur
face they cause pudding of the soil
and consequent driving up of air, which
in short time Nrrests the downward
action of the water making it seep
more and more slowly, until practi-
cal standsti2l occurs The result is
generally hardpan.
AS irrigation is usually practical but
one way through the orchard a deep
subsoil track or tunnel should be run
half way between the trees transversely
the streams. This can be done with
small tool on a sub-soil plow shank
big enough to make a track about the
HsNO " q 9OPAOA L I'LL cC q uCplA VI III
teen to twenty inches. The benefits
accomplished by this are the dissem-
ination of water all around the trees,
the more rapid spreading of the water
without driving out the air, as in the
deep furrow, and the carrying of the
air deep down into the soil, thus as
sisting irrigation. This may be OBJ
jected to as a root pruning operation
which it certainly is, and on this ac-
count it is not practical in all sea-
sons. This is to be regretted because
1t is great advantage to irrigation.