Judith Gap journal. [volume] (Judith Gap, Mont.) 1908-19??, 1911-11-10
ALKALI.
BY Edmund Burke, Chemist,
Montana Experiment Station.

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Alkali is q popular term applied to
soluble salts found u the soil ia many
parts Of the country. These salts
were formed at the time the soil was
forming through diantegratiou of
rock material. Where the rainfall
was SUFFICIENT to leach them from the
soil and to carry them on to ind their
way ultimately into the oceans or in
land lakes, tho land IL comparatively
free from alkaii. In sections where
the rainfall was not sufhcient to leach
them out, they remained In tho soil
and are now found IN different quaint
ties and at different depths, depending
upon the character OF the soil and the
depth to the water.table. Wateftable
is the term used to designate that
point to which the grOund-water risee
and Ails all the pores In the soil.
We have two kinds Of alkaM, COM
monty known a. white all1AN and
black alkan. White alkaM 10 composed
chiefly Of magnesium sulphate (Ep-
som saks>. sodium sulphate (olauber's
sAlt). and sodium chloride liable salt),
and 10 the moro abuadant and widely
distributed. It 10 called white alkaN
because Il forms q white iucrustation
On the surface II the soil where it has
bsen brought and Aspesstsd BY the
upper movement and evaporation OF
he water. WAea water 10 applied to
allnaM sofia. either - rain or BY irri.
cation. the alksu = again carried into
the soil. only - yesurn to the surface
when the vaenr again evaporuees.
Biack alhaN 10 composed nainly Of
sodium carbons4e zeal soda or wash
ing soda). II = found IN only . few
localities II Monaasa IA euaoettlss suf.
Acisat to Do harmful. Il 10 called
black alhalt becaSoo q hes the power
= dtssssVe como d ~ organic matter
IN the cell. which gavea Il . bFownish.
black oo1er when Il terane IN iocrusta-
tfon On the surface a the ground.
Black alkali p not only injurious to
plant growth but II also destroys part
OF the osgaolc meter which 10 essen
tlal to crop production and destroys
the texture OF the SOIL In comparing
the injurious effects Of those two A.
kalies 1t may be said that black alkan
10 far more Injurious to plant growth
that the white. Black alkaN may.
however. be changed to white alkali
by applying sypsum or land plaster to
the land.
From what has already been said It
is evident that the alkalies are car.
ried down into tho soil by water. In
irrigated districts two conditions may
arise. First, where the soil is shall.
low. water may be added TO the soil
until it finds an underground outlet
The water which passes down through
the soil carries the alkali with it, but
this water usually comes to the sur.
face at some lower point, depositing
an excess Of alkali on the ground. For
this reason farmers should guard
against the seepage of canals and
should not let water run on the ground
for too long a time. as Is now done In
the irrigation of meadows
Second. where the soil is deep, irri.
CATION water. when excessively used.
sinks to considerable depth in the soil
only to return through the action OF
capillarity bringing to the surface the
salts which it has dissolved. Such
soil should be treated once with
enough water to carry the alkaii into
the soil to depth where It will not
come in contact with the roots Of
grain. and then. where possible. the
ground should be cultivated so az to
reduce the evaporation and keep the
a!kali below the roots OF the plants.
1t Is always to be remembered that OK.
cessive irrigation causes a rise of the
water-table already referred to and so
corresponding rise of alkan.
The injurious effects OF alkali may
be greatly reduced by proper cultiva.
ton. but the only method Of remoy.
ing the alkali from the soil ia by
under.drainage and flooding the land
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