The progressive farmer. [volume] (Winston, N.C.) 1886-1904, 1901-03-19

Tor cotton. It is also true that a
relatively, as we'll as absolutely,
larger amount of nitrogen is found
In the 1,5OO pound cotton crop. But
In the fertilizer formulas found to be
best suited for these crops respect
lively, the relative proportion of
nitrogen is nearly twice as great for
corn as for cotton.
These facts indicate that there is
a difference between the appropriat-
ing and assimilating powers of diff
ferent plants, and it has not been
made to appear that there is any
relation between this difference and
the composition of the respective
plants. In the cases of corn and
cotton it is suggested that the former
is a grosser feeder, and may be able
to utilize the potash found in the
soil to larger degree than can the
cotton. 1t may also be true that the
corn plant has less appropriating
power over the nitrogen compounds
in the soil and air than is exercised
by the cotton plant. At any rate,
whatever may be the true explana-
t1on, we are confronted by facts,
and theories may we'll stand aside
when determining practical methods,
and await laboratory research and
demonstration.
A remarkable fact, a paradox it
may be called, will appear on a little
further examination of Table 1 Ten
years of field experimentation on the
varying soils of the Georgia Expert
ment Station Farm have enabled me
to reach what consider a very close
approximation to the relative com
position of fertilizer that gives the
best results when applied to cotton
in amounts varying from 400 to 800
pounds per acre. The formula may
be thus stated:
Acid phosphate IA per cent.
available) ).................1,O , 900 lbs
Muriate of potash $50 per
cent. K2O). O)............... rs lbs
Applying about $50 pounds of the
formula to an acre capable of pro
ducing 1,50O pounds of seed cotton
would ordinarily cause an increased
yield of 500 pounds of seed cotton.
Fifteen hundred pounds of seed
cotton require, phosphoric acid AZ
pounds, potash 80 pounds, nitrogen
81 pounds.
Apply $50 pounds of formula, phos-
phoric acid so pounds, potash Is
pounds, nitrogen Is pounds.
Resulting 500 pounds increase seed
cotton, phosphoric acid IA pounds,
potash 81 pounds, nitrogen 20 pounds.
You see we have applied so pounds
of phOsphoric acid and received in
the increased yield only IA pounds.
What has become of the 36 pounds?
We applied 15 pounds each of potash
and nitrogen and recovered in the
increased yield 81 and 20 pounds re
spectively. Where did these come
from? The necessity of adding more
plant food than is required by def
mite increase in the crop is we'll
recognized by agricultural writer's.
Prof. Ville's theory on this point is
based on the following propositions
"0) Give the earth more phosphates,
more potash and lime, than the har-
vests have taken from it. (2) Give
it so per cent. of the nitrogen they
contain" He probably means that
the applied fertilizer should contain
more phosphates (phosphoric acid),
more potash, and more lime, than
the expected increased yield would
require, and one-half as much nitro,
gen.
These facts, the result of direct
experiments-point to the conclusion
that the only reliable and practicable
method of ascertaining the fertilizer
needs of the soil with reference to
the production of any particular crop
is to apply to the soil different pro
portions of the valuable elements
and note carefully the results. This
method is in common use at the sew
eral experiment stations, and by
few intelligent lay experimenters
throughout the country. To ask the
soil whit it requires is the only way
to secure a reliable answer. 1t is
practicable for any intelligent farmer
to ask the question in this way. 1t
is the natural way. It can be asked
of any soil and with regard to any