The Billings gazette. [volume] (Billings, Mont.) 1896-1919, 1899-02-10

ing. The planters do not realize Tin
deed, how a they, not seeing the con
ditions under the surface) that the
water is accommodating there, and al
though it may not be rising rapidly
enough to injure themselves, it may be
seeping down and gradually inundatinq
their unfortunate neighbors on lower
levels.
IF these Investigations do no more
than to show the full results Of over.
irrigation and the necessity of intelli-
gent and careful application Of water to
the soil and the Importance of under.
drainage, where the alkali cannot be
otherwise controlled or removed, the
authors will be we'll repaid.
Proper irrigation in an arid region
furnishes an ideal condition Of crop
production. In practice, however, the
method of applying water to the land
is extremely crude. and there is really
little cause to wonder that much harm
has been done through over-irrigation,
and it is no wonder that very serious
trouble has occurred through the rise of
soluble salts.
The soils division has invented an in
strument for use in irrigated fields, to
cost not over $40 apiece, SO that for a
moderate expense enough of these could
be distributed. even over a large plan
tation, so that the fluctuations of the
water content Of the soils of the differ
ent fields can be closely studied and
controlled.
Field work in the alkali soils at Bill
ings has shown that when the concen.
tration of the salts in active solution in
the soil moisture is as high as / per
cent the limit of most cultivated
plants is. reached. Further concentra-
ton kills all our ordinary agricultural
plants.
It was important to know the amount
of soluble salts in the principal types Of
soil, which had been kept under APP
proximately the same conditions as to
exposure, cropping and irrigation. 1t is
important to determine the amount and
distribution of the salts above the ditch
where the land had never been irrigated
and in the irrigated districts, and it
was furthermore important to study
the distribution of the salts in soils
which had been or were now being
ruined by the presence of alkali.
AS a result Of the Investigations at
Billings it was found that plants could
just exist with 0.45 of l per cent of the
soluble salts present, equivalent to
about Is, 600 pounds per acre foot, and
this is taken as the limit of plant pro-
duction. The soluble salt content of
soils in the humid portion of the
United States ranges from SO pounds
per acre foot in the sandy soils of the
Atlantic coast to as much as 5000 or
1000 pounds in some of the heavier
agricultural soils. The average amount
would be considerably less than 1000
pounds per acre foot.
Professor Whitney continues: "Some
of the planters are much inclined to ac-
cept the prevailing conditions and to
look for crops like the Australian salt
grass, which will grow in these alkali
flats and wet soils. It is wrong to ac-
cept these conditions, however. and de-
pend upon make shifts. when the con-
ditions ought in the first place to have
been prevented and ought now to be re-
moved by radical and energetic methods
Of drainage or through better and more
careful methods of irrigation. The
first harmful effects observed in these
sandy soils is caused by an excess Of
water, and if this is not Immediately
lessened further damage will result from
the accumulation Of soluble salts. If the
excess Of water is soon removed no per-
manent damage will result.
"The heavier type of soil was shown
to be derived from the disintegration Of
the shale. The still undecomposed
shale in the bluffs on the south side of
the valley was found to be penetrated
in every direction with veins of gypsum
and tie soft shale itself to be permeated
with large quantities Of sodium and
magnesium sulphates. The soils re-
sulting from the dis%integration of the
shale form a heavy, sticky, blue clay,
quite impervious to water. The drain
age is SO slow through this fine. i'm
p~ervious material that large quantities
VI ouo odAto IoHld1u III uIl0 SOl1. .
ION account Of poor drainage and
the slow movement of the subsoil
waters through this material there is
great danger Of over irrigation, and the
problem of irrigation. which is easy on
the well-drained, sandy lands, becomes
far more complicated and much more
difficult to manage on these heavy
gumbo soils. Great care has to be
taken, not only in the application of
water, but in the actual cultivation of
these soils, as they are liable to be
ruined for a time at least for alfalfa.
1.-The formation of these alkali flats
is an evidence of the effort of nature to
correct the faults of our crude system
OF irrigation. The salts are being car
ried off into the natural drainage of the
country. but the process is very slow