Decorah public opinion. (Decorah, Winneshiek County [Iowa]) 1895-1928, 1906-05-02


barring the air we breathe, with which
we come in closer contact than the
soil under our feet, yet at the same
time no element about which we pos
sess less specific information. 1t is a
wondrous realm, full of fascination
and interest. Farmers bulletin No.
245, issued by the United States de-
partment Of agriculture and entitled
Renovation of Wornout Soils" con-
tains mine of information on the sub
ject and should be in the hands Of
every farmer and be studied as a
primer of agriculture. 1t Is from this
we CLEAN the following facts about the
soil and plant life: The soil consists
of organic and inorganic matter. I'm
der the first heading are included all
elements in the soil that are subject
to vital processes growth and decay;
are not subject to these changes-i. e.,
minute portions of stone and gravel.
The elements named are permeated by
the soil air and water. 1t is the latter
the moisture in the soil-that con-
tains the plant food substances, and it
is these that possess most interest and
value from the human standpoint.
These substances are divided into two
classes, according to their ultimate
source. The soil furnishes nine of the
thirteen chemical elements used In
plant growth - phosphorus, potassium,
calcium, sodium, iron, silicon. chlorine
and sulphur. Nearly all varieties Of
rock particles, of which the soil quite
largely consists, contain more or less
Of these elements. Every year the soil
water dissolves a thin surface layer
from each particle, and 1t is this solu-
ton which furnishes the plant its min
eral food.
In addition to the elements named,
the plant in its growth requires hydro
gen, which it secures from water
(which is compound Of hydrogen and
oxygen; oxygen, which it secures part
ly from water and partly from the air;
carbon, which is secured from the car
bOnic acid gas in the air, and nitrogen,
which in many respects is the most i'm
portant of all the plant food elements.
AS it is not found in the rock particles
of the soil, plants have to depend for
their supply upon decaying organic
matter-manure and other fertilizers.
Being very soluble, the nitrates quickly
wash out of the soil unless appropriate
ed by growing crops. 1t is in supply
ing nitrogen to the soil that the le-
gumes possess so great value for the
agriculturist. There is a certain spe-
cies of bacteria that can use atmos-
pheric nitrogen, the supply of which is
unlimited, and the clover, bean and pea
families have learned to swap work with
them. When these bacteria are pres
ent in soil in which leguminous crops
are growing they invade the roots OF
the plants and live there. their presence
being shown by swellings-tu bercles.
the roots, where the bacteria appropri-
ate it, manufacture an abundance OF
nitrates and give it to the plant in re
turn for starch. The tissues Of the
plants thus become very rich In nitro
gen compounds. which they set free
when decay sets in and which are
available for any growing crop. A
condition of soil that likewise greatly
favors the growth of the plant is pro-
duced by humus, decaying vegetable
matter, which may or may not be rich
in nitrates, but which renders possible
proper circulation of air in the soil
and those chemical actions which ac-
company a decay of organic matter
One of the most important. objects OF
blowing is thus seen to be loosening
of the soil and a mixing of fresh air
with 1t. This is but part of the story
but still enough to show that fixed nat
ural laws underlie and govern all agli-
cultural operations, and that there Is
no field of effort where greater meas
ure Of intelligence is needed nor in
which intelligent effort is more surely
or generously rewarded.