Graham guardian., 1905-03-03

soil section. The water table plays
but little or no part in the accum-
ulation.
RECLAMATION OF ALKALl LAND.
There is always a tendency IN
irrigated districts to use greater
quantity of water than is actually
necessary. This excess, unless
carried away through efficient
natual or artificial drainage chan
nels, sooner or later results in rails
ing the water table. At the pres
ent time but little of the irrigated
lands of the valley are in need of
drainage, Should future irrlga-
tion result in raising the water
table, however, as is likely, trouble
will enuse, especially in the heav-
ier soils. When the water ap.
proaches within six feet or less of
the surface the limit of safety is
reached and provision should at
once be made for carrying away
the excess of water. Tile or open
drains at intervals of one eighth
or one-fourth mile will assist great
ly in keeping the water table be-
low the danger line.
Among the most prominent
methods proposed for retaining
alkali lands may be mentioned the
removal of the crust by scraping,
the application of chemical cor
receives, the growing of alkali-
resistant crops, and drainage. OF
these only the last mentioned is
thoroughly effective, since it is the
only method which removes the
cause of the trouble. Some of the
other methods may, however, be
used with good results in con
nection with drainage.
The removal Of the alkali salts
by scraping the surface calls for
much labor and must be constant
ly repeated, any good that may
result being merely temporary.
This method need receive little
serious consideration
The application of gypsum IS
practiced with beneficial results in
soils where there occurs an excess
of sodium carbonate or "black
alkali". In this case chemical re-
action takes place, and the injur-
ious carbonate salt is changed into
the less injurious "white alkali".
This method alone does not re
move the cause or permanently
improve the land, aud Fit is but a
question of time until the white
alkal itself will accumulate in
sufficient quantities to be destruct
i've of plant life.
The utilization of alkali lands
and the gradual removal of the ex-
cess of alkali salts have been at
tempted with partial success by
the growing Of certain aIkali-re-
sistant plants of more or less
economic value. The harvesting
of the crop In the case of such
plants removes considerable
amount of the alkali salts, which
have been taken into the plant
tissues and cells, This method is
successful only to a limited extent,
and, like the others mentioned, it
fails TO remove the cause. 1t is
worthy of notice, however, that
some field crops Will thrive in the
presence of a greater quantity of
the alkali salts than others. THIS
is true particularly .ot sorghum,
sugar beets, and alfalfa. Land mp
on which the injury from alkali is
slight, hut sufficient to damage the
less resistant crops, should be
used for growing these harder
crops.
But it is through drainage of the
land that must be considered the
only practical and efficient remedy
for the reclamation of alkali lands.
This alone removes the cause by
doing away with the excess of
seepage water and lowering the
water table. 1t both checks furth- l.
er accumulation and makes posi-.
BILE the removal of the salt already
in the surface soil. A system of
open drains will do, but lines of
tile at frequent intervals are not
only more efficient, but are no
hindrance to cultivation, and are
permanent. The intervals be-
tween the drains will vary with
the rate of flow of water through
the soil, and can best be deter
mined in an area by experiment on
a small scale. The depth should
be such as to keep the water table
below the danger line, which, in
this area, is not less than six feet.
The drainage of large areas In
to the Gila river might, in time of
low water, increase the salt CON
tent ofIts water to such an extent
as to impair its fitness for irriga-
tion. But with the gradual ex.
tension of drainage through the
the limited area requiring it in this
district the effect would be neg
ligible.
After the installation of the
drainage system the salts should
be removed by washing them out
through the drains by frequent
nnndinn of the land. Tho wntnr