Semi-weekly south Kentuckian. [volume] (Hopkinsville, Ky.) 1883-1889, 1886-10-15
COMPOSITION OF SOILS.
A Study Which Every Intelligent Ian
Owner Should Pursue.


Owner Should Pursue.
There is no more important study for
the farmer than careful study of his
soil. While soils are composed of three
distinct constituents-sand, clay and
humus--yet these vary greatly in their
composition. All soils, as far as their
Inorganic materials are concerned, were
originally composed by the breaking
down and decomposition of rock.
Sands result from the decomposition Of
quartz, or other rock containing quartz
or silica in some form, and the compost
ton of each individual grain is that Of
the rock from which it was formed.
Soils formed of granite are among the
most productive known. Why? Gran
ite is composed of quartz, feldspar and
mica. The quartz is pure silex, so
necessary for the proper division Of
soils. Fcldspar again consists of silica,
alumina and potash. Alumina is the
base of clay, just as the metal aluminium
is the base of aluminS, alumina being
an oxide of aluminium, and is the char.
acteristic ingredient in all ciays. With
out il soils could not be combined and
held together. With too much alumina
it becomes too dense, hard and impervi-
GUS both to water and the roots Of
plants.
Humus is any organic matter in pro-
cess of decay or in that state when ro-
duced to an impalpablo powder. Prai-
rie soils contain great deal of humus
that seems to have been deposited when
the soil was under water or partially so.
So the fact that thesa soils, as rule,
are largely composed of clay. are due
their fertility and lasting qualities, the
dark color of the soil being due to
humus, and also to the effects of burn
ing of the vegetation year after year.
Soils are generally classed as sandy,
loamy, clayey, mucky and peaty, the
latter being formed in marshy land un-
der water. Our very black prairie soils
containing much clay and vegetable
matter, are often designated muck. A
distinctly clay soil is that composed OF
pure clay, Pure sand has no fertility,
pure clay can not be classcd as fertile,
and pcaty soils are not fertile until they
have long been uncarthed by careful,
thorough drainage. -r,..
Mixtures of sand and clay are our
most fertile soils. They are classified
as loan when they contain equal vol
umes of sand and clay, as sandy loan
when about seventy-fivo per cent. is
sand, and as clay loan when about
scventy-iivo per cent. is clay. AS soils
approach either of these conditions they
are classed with that to which they re-
late most closely,
The province of fumus in the soil is
two-fold; TO render the soil light and
mellow, though its principal value. is
the power that humns possesses of de-
composing and rendering soluble the
valuable constituents of the soil, es-
pecially those of potash with nitrogen.
Humus is formed by the action of the
air on solid animal orvegetable matter.
In fact, it is process of exceedingly
slow combustion, as much as five hun
dred years being considered necessary
to reduce a large oak to humus in the
natural progress of decay. During all
this time, however, such portions as
are gradually converted into humus are
performing their natural functions in
the soil. One of the most important is
the conservation of nitrogen-the most
costly, as it is tho most easily dispelled
NJ thn ornnnic nrOductS IIndar tho