The Filler
Categories:
HOME-MIXING OF FERTILIZERS
There has been much misleading use of the word "filler,"
as applied to fertilizers. We have seen that a pure grade of dried
blood contains about 13 per cent of nitrogen. The buyer of a ton of
dried blood thus gets about 260 pounds of plant-food. The remaining
1740 pounds constitute what may be called nature's "filler." The blood
is a good fertilizer. We do not buy nitrogen in a pure state. We buy a
ton of material to g
t the needed 260 pounds of nitrogen. Thus it is
with nitrate of soda, sulphate of ammonia, acid phosphate, muriate and
sulphate of potash, and all other fertilizer materials. As freight must
be paid upon the entire ton, it usually pays best to select materials
that run high in percentage of plant-food. It is possible to get very
low-grade fertilizers that have not had any foreign material added by
the manufacturer. An acid phosphate may be poor in phosphoric acid
because low-grade rock was used in its manufacture. Kainit is a
low-grade potash because the impurities have not been taken out. Filler
may be used, however, for two reasons, and one is legitimate. When
limestone or similar material is used merely to add weight, reducing
the value per ton, the practice is reprehensible. The extent of this
practice is less than many suppose, preference being given to the use
of low-grade materials in making very low-priced fertilizers.
A legitimate use of filler is to give good physical condition to a
fertilizer. Some materials, such as nitrate of soda and muriate of
potash, take up moisture and then become hard. The addition of peat or
limestone or other absorbent is necessary to keep the mass in condition
for drilling. The use of some steamed animal bone or high-grade tankage
in the mixture helps to prevent caking. The home-mixer can use a drier
without loss, as he does not pay freight upon it. Dry road dust will
serve his purpose. His need of a drier may be greater than that of the
manufacturer, as he probably will use only high-grade unmixed
materials. If the use of the home-mixture is immediate, no drier to
prevent caking is needed, but its presence facilitates drilling.
Storage of unmixed materials in a dry place is an aid in maintaining
good condition.