The Dawson news. (Dawson, Ga.) 1889-current, 1901-06-26
ABOUT FERTILIZATION.
THE SOIL AND ITS RELATIONS TO
ATMOSPHERIC CONDITIONS.
Important Subject of Interest to All
Agriculturists Further Discussed
by Georgia state Chemist.
LETTER NO. 2.

All living things, both plant and AMI"
NAL, may be traced back to two sources,
the soil and the atmosphere. In the
last analysis every particle of which
they are composed must have been de-
rived either from the air or the earth.
The food derived from the air is by far
greater in quantity than that from the
soil, but as the elements of plant food
In the atmosphere automatically renew
themselves, there need never be any
fear that the atmosphere will be ex-
hausted of the elements Of plant food
which it contains: the soil, however,
is different proposition. The elements
of plant food contained are mnch less
abundant than in the air; in fact, many
of them are quite limited in quantity,
and the best efforts of the farmer are
; needed to improve the condition of his
soil so as to render the plant food in it
more available; to prevent such plant
food as exists from washing away,
and to add plant food from any other
available sources The soil is any part
Of the earth's surface which is capable
of cultivation and of the production of
crops.
The biologists tell us that when
the earth first cooled down from a mol.
ten condition there was no soil any
where, but only rock, great granite
! boulderS and rocks of other nature, but
that in the vast periods of time which
elapsed between the cooling down of
the earth's crust and the time when
man and other animals began to APP
pear on the earth, the rocks had
rotted and crumbled away and pro.
duced what we now know as the soil
and subsoiL The rain falling upon the
rocks sinks into the cracks and assures,
and, freezing therein, tears and fakes
| off small particles; these III turn, being
swept along by floods, are ground
against each other and gradually re-
duced TO powder. The oxygen of the
atmosphere also exerts a chemical effect
| in converting some OF the minerals into
oxides. For instance, if you leave a
| bright. new ak out exposed to the
weather you will soon note coating
| upon it which you call rust; that is
produced by the action OF the oxygen
| of the air upon the iron Of the ak, and
| is really the oxide of iron. In this way,
| then, by the action of water in freezing
and rhawing, i'll grinding and trans
porting the broken fragments of tine
| rock and by the action of the air IN OK
idizing the minerals going on for many
| thousands and thousands of years, pos
sibly millions of years, the rocks have
been gradually converted into what we
now know as the soil and subsoil.
| The subsoil may extend down only a
| few feet, or il may extend for many feet,
but when yon get TO the bottom of it
you will strike the rock, usually the
same kind of rock from which the soil
was originally derived. Soils may be
divided into these general classes
sandy, clayey, limy and peaty, accord
ing TO whether their principal ingre-
dents consist of sand, clay, carbonate
of lime or vegetable matter. A soil
which contains over 70 per cent of sand
is called sandy. Such soils usually con-
tain but little plant food. They are Ill
adapted to withstand drought, as the
sandy particles absorb and retain but
! little moisture and the crops would
soon burn up i'll long dry season; but
when the rainfall is abundant ar irri-
CATION is at hand these soils are desira
BILE, because they dry out quickly. per-
NIT the easy cultivation of the crops
and respond quickly TO liberal fertiliza-
ton. They are especially adapted TO
, quick growing crops.
so per cent of clay, and is exactly the
reverse of the sandy soil. Water perco-
lates through them very slowly and in
very wet season the crops OH them
suffer from the excess of moisture. They
are also more difficult to cultivate
These lands, however, are usually rich
er in plant food. They are well adapt,
ed to the grains and grasses. Limy
soils, lime soils, or calcareous soils, are
those which contain over 20 per cent of
lime. The lime exists in these soils III
the form of carbonate of lime, and is a
very valuable element of plant food. It
is itself absolutely essential to the plant
and il also aids i'll breaking up mineral
combinations in the soil. and so render
! ing other elements of plant food avail
able which would otherwise remian In
soluble and therefore inert.
Lime also aids materially in the
decay of organic or vegetable mat
ter in the soil; it also improves