The Florida agriculturist. [volume] (DeLand, Fla.) 1878-1911, 1878-07-10
Lime as a Fertilizer.

~ ~ AAnic OH SOILS, ana Its
uses and value, are very clearly set
forth in the following extract from q
report of Mr.. Falconer King, a Scot.
tishagricultural chemist of established
reputation
In considering the part played by
lime in agricultural operations. It
should always be remembered that
mat substance acts in the soil in two
perfectly distinct and separate ways.
rirst' lime acts as manure, by sup
plying necessary calcareous food d.
rectly to the plant; and second, it
acts by supplying food indirectly to
the plant, either by unlocking the
storehouse ofplant food already exist
ing in the soil, or by converting use
less or even deleterious ingredients
Ihereof INTO substances useful, or at all
events harmless, to vegetation.
Lime, as is well known, is required
directly by all cultivated plants as
food, and therefore a soil which is
totally devoid of lime is simply bar
rem, and the obvious remedy by which
to render such a soil fertile would
be OF course dose of lime. Such a
case as this, however, is extremely
rare. Of all the suspicious soils
which l have analysed, cannot recall
one to mind which was proved to
oweits barrenness to being completely
devoid of lime.
In most cases, therefore in which
lime acts beneficially when applied to
the soil, it does so either by supply
ing food to the crop indirectly, or by
destroying some noxious constituent
already existing in the soil.
The plant food which lime supplies
indirectly may be divided into two
cIasses-frst, mineral or inorganic,
and secondly, vegetable or organic.
The principal member OF the first
class seem to be silica and potash
These substances, however, it should
be borne in mind, are not i'm anv way
contributed to the soil by the lime
they are merely changed by it's action
from their hard, stony, insoluble
nature into a condition in which thew
are available to plants as food. These
two substances, silica and potash, are
found in greater or less proportion in
almost all fertile soils, but in some
soils they exist principally in an in
soluble or locked up condition, if I
may use the expression, and are there
lore of no use as plant food until they
have been set free either by the action
of lime OF by some. other suitable
agent.
The principal members of the sec
ond or vegetable class of food mate
rails which lime prepares for the use
of plants, is nitrogen. Now this sub
stance nitrogen, as is well known, is
an indispensable and most valuable
ingredient ofplant food, and therefore
any substance which can apply it to
plants in a readily available form is
an egent of very great utility. This
office is performed, and performed
very satisfactorily, by lime. The
lime does not, indeed, add or contrib
ute any nitrogen any more than it
adds potash to soils, but it converts
the nitrogen which, though it already
exists in the soil, is present in COM
paratively inert state, into form in
which it is easily assimilated by
plants. In these different ways,
therefore, may lime be used with
great benefit, viz on soils which con-
tain a large quantity of undecomposed
mineral matter, and on soils which
contain an excess vegetable matter
Lime, however, is useful in another
way, and that is by destroying sub
stances hurtful to vegetation, such as,
for example, certain compounds of
iron and certain acids, which are al
legged to be the cause Of the peculiar
evil known as sourness. A soihit is
we'll known, may contain all tie in
gradients necessary for supporting
plant life, and yet be unfertile in con
sequence of containing some deleter-
ious or poisonous ingredient. Lime
may act, therefore, very benefcially
on some soils, not by providing an
increased supply Of plant food, but
merely by neutralizing or destroying
some such hurtful substance which
may be present.
In all the instances have men,
toned, lime, we have seen, acts bene-
ficially; and it now remains for me,
before concluding this short note, to
point out, in a very few words, how
lime may act prejudicially-so act,
indeed, that its continued application
may not only be useless, but actually
be hurtful. 1t is an old idea that