The Sauk Centre herald. (Sauk Centre, Stearns County, Minn.) 1886-current, 1912-05-02
Commercial
Fertilizers.
BY Ralph HoagIand, Professor
Of Chemistry, Minnesota COL
Iege of Agriculture.

:. Iege of Agriculture. :.
4. + i. !. j. :. = !. !. j. !. i. + j. !. i. !.
A commercial fertilizer is a concen-
trated plant food, containing, in vary.
ing amounts, one or more of three
elements which are absolutely essen
tial to plant growth. These elements,
nitrogen, phosphorus and potassium.
are no more important for plant
growth than certain other elements
found in the soil; but because they
are removed in the largest amounts by
cropping they are the first to become
deficient in the soil. When a soil is
naturally deficient or becomes def
cient, in nitrogen, phosphoric acid or
potash, the largest crop yields cannot
be obtained until this lacking plant
food element has been supplied. 1t
may be done in several ways. The
growing of clover is the cheapest way
to supply nitrogen; the use of farm
manures the best way to supply all
the elements Of food, provided such
manures can be had in sufficient
amounts. The right place for a com.
mercial fertilizer, in an intelligent sys-
tenn Of farming, is to supply needed
plant food, so as to produce maximum
crop yields, when the same results
cannot be gotten more cheaply by the
use of farm or green manure, or the
growing of clover in a system of crop
rotation.
Commercial fertilizers are divided
into two general classes: First,
amendments, or fertilizers containing
single plant food element, as nitro
gen, phosphorus, or potassium; second,
complete fertilizers, or those contain
ing all three elements in varying
amounts, mixed in such proportions as
to suit the needs of various crops.
ACKNOWLEDGEMENTS of soda is
the most common fertilizer containing
nitrogen. 1t is a mineral, mined and
refined in Chile, and looks like crude,
coarsely crushed salt It contains
about 16 per cent nitrogen, and costs
about $57 ton. It is all soluble, and
is specially adapted to quick growing
leaf crops.
Dried blood, slaughter house BY
product, is valuable heterogeneous fer
tilizer, containing about Is per cent
nitrogen, and selling for about $55 a
ton. It is adapted to the same uses,
but is less soluble than nitrate of
soda; thus furnishing the element,
nitrogen, throughout the growing sea-
son.
Acid phosphate is a phosphorus fer
tilizer, prepared by treating phosphate
rock with sulphuric acid, to make the
phosphorus soluble. It contains about
IA per cent of soluble phosphoric acid,
and sells for about $18 ton. Phos-
phorus performs very important
function in the plant, In seed forna-
ton, and phosphate fertilizers are
largely used in grain growing.
Raw rock phosphate Is simply the
untreated rock. It is valuable as a
fertilizer only when used in connection
with an abundant supply Of farm or
green manure. It contains about 30
per cent phosphoric acid, and sells for
1920 ton t. o. b. st. Paul.
Bone meal consists of finely ground,
either raw or cooked bones, from the
packing houses. It is essentially a
phosphate fertilizer, although the raw
bone meal contains fair amount OF
nitrogen. 1t contains from 20 to. rs
per cent phosphoric acid. and 1.5 to
per cent nitrogen, and sells for from
$40 to $50 ton, according to compo-
sition.
POTASH FERrlLIZERs.-S ulphate
Of potash is one of the principal fer
Iilizers. 1t is mineral salt, contain
ng about SO per cent potash, and sells
'or about $5S ton Potassium is an
important plant food element for grain
grasses and especially potatoes. Pot
ash fertilizers are usually not applied
alone, but. in connection with phos-
ohate fertilizers. for grains, grasses
md potatoes. Potash alone has been
ound to give excellent results on the
,eaty soils of Illinois and wisconsin
Muriate OF potash contains about
he same amount of potash as tn
'ulphate; is slightly cheaper, and ha
he same uses.
The market values of mixed fertil
zers usually correspond to their COM
richer in plant food, the
igh0r the price: the lower in plant
God, the lower the price. There Is no