Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1915-02-02
(To be continued.)
FORMULAS FOR FERTILIZERS
Clemson Expert Tells How they May
be Fiqured Out.

Clemson Expert Oils 1oW they way
be Figured Out.
Calculating a fertilizer formula is a
hard task for any one who does not
understand certain principles on which
the calculations are based and a very
simple task for one who has learned
these few rules. Home-mixing Of fer
tilizers, which was strongly urged by
Clemson college last year, with good
results, will be even more strongly
urged this spring. T. E. Keitt, chem
ist Of the South Carolina experiment
station at Clemson college, has pre-
pared a brief circular which will in
struct any farmer how to calculate his
formulas for home mixing and this
circular Is to be had by writing to the
extension division Of Clemson college.
Prof. Keitt writes in part:
In calculating fertilizer formulas,
unit is per cent Of ton, and, as there
are twenty hundred pounds in ton,
there are always 20 pounds in a unit
When we speak of fertilizer formula
such as "S-4-4," we mean that there
are eight units or 160 pounds Of actual
phosphoric acid, nitrogen equivalent to
four units, or 80 pounds Of ammonia,
and potash equivalent to four units or
so pounds Of potash. The order OF ele-
ments in naming formulas is always
Phosphorous-Nitrogen-Potash.
In home-mixing fertilizer 1t is ad-
visable to have two sources Of am
monia, one rapidly available, which
can be derived from nitrate Of soda,
sulphate Of ammonia or dried blood.
Two thirds Of the ammonia should be
procured from a gradually available
source, as cottonseed meal, fish or
tankage.
1T pays to buy high-grade acid
phosphate, and muriate Of potash Is
the most economical source Of potash
for general farm crops, but should not
be used on tobacco or potatoes.
Suppose we desire to make for
mula that will analyze S-4-4 from 16
per cent acid; two sources Of ammonia,
IS per cent nitrate Of soda and per
cent cottonseed meal; and 4S per cent
muriate of potash.
"One- third of 80 pounds Of ammonia
(four units) is q pounds, to be derived
from nitrate Of soda. Each 100 pounds
of soda contains nitrogen equivalent to
IS pounds of ammonia. Therefore, II
we divide o. the number Of pounds OF
ammonia desired, by Is, the number or
pounds in each 100 of nitrate Of soda,
we get Is, the number Of hundreds Of
pounds of nitrate Of soda required to
furnish 81 pounds Of ammonia; that
is to say, $50 pounds Of nitrate of soda.
This leaves SO pounds Of ammonia
to be derived from cottonseed meal.
each 100 pounds Of which contains
pour.ds of ammonia. Calculating SINH
larly, we have SO divided by I, getting
as an answer 157 pounds Of cottonseed
meal.
In addition to it's nitrogen -equiva-
lent to ammonia content, cottonseed
meal contains per cent Of available
phosphoric acid and u per cent of wa
ter soluble potash. Therefore, 75I
pounds Of cotton seed meal will furnish
in addition to ammonia, Is pounds OF
phosphoric acid and II pounds of
water soluble potash.
Our mixture was to contain l60
pounds of phosphoric acid Is units),
but Is pounds are contained in the
cottonseed meal, leaving 145 pounds to
be derived from Is per cent acid phos-
phate. Then 145 divided by 16 equals
9O6 hundred pounds, or 906 pounds Of
16 per cent acid.
THE formula requires 80 pounds OF
potash a units), but II pounds have
been furnished by the cOttOnseed meal
leaving 50 pounds to be derived from
8 per cent muriate Of potash. Then
60 divided by 4S equals 1.44 hundred
pounds, or 144 pounds Of muriate OF
potash"
This S.4-4 fertilizer will, therefore,
contain $50 pounds nitrate of soda, 151
pounds cottonseed meal, 906 pounds 16
per cent acid phosphate, 144 pounds
muriate of potash. This gives 1857
pounds. If desired for purposes Of fa-
cilitating measuring to make an even
ton, it is done by adding 43 pounds
filler.