Savannah courier. (Savannah, Tenn.) 1885-1979, 1897-02-05
FARMER AND PLANTER.
SCIENTIFIC FACTS.
Tho Dissolving Power Of tho Roots o


Tho Dissolving Power Of tho Roots Of
Plants.
That all cultivated plants take their
food only in the form of solution, and
this almost exclusively directly from
the soil by means of their roots, are
facts generally recognized The meth
DDS by which the result is accom-
plished are. however, comparatively
unknown, yet their practical bearing
on the problem of plant nutrition and
food supply Is of vital Significance.
Water passes through the soil taking
but little soil-matter with it in solu-
tion, showing that the plant-food con-
stituents are comparatively insoluable
in water. Much of the material added
TO soils as sources OF fertility is like
wise only partly soluble in the moving
waters OF the soil. 1t is therefore APP
parent that the elements of nutrition
either naturally or artifcially present
in the soil would be comparatively in
accessible to the growing crop, but
would remain locked up in the soil.
were the dissolving power OF water
the only available means for its con.
version into solution and thus bccom-
ing assimila BILE to the plant.
The roots of plants, however, are en-
dowed with the power Of dissolving
their own food when not otherwise
available. The roots possess the prop
erty Of secreting an organic acid,
which, being exuded from the growing
tissue, comes in contact with the in
soluble ingredients Of the surround
ing soil and acts Us q solvent on the
same, much as the gastric juice of
animals acts on the food In their
stomachs, rendering the food constit-
uents soluble, and reducing to solu-
ton, 80 that it is readily taken up,
and entering the plant through the
same roots, is assimilated and becomes
the new tissue in the growth and de-
velopment Of the crop. The practical
bearing of this fact lies in the fact that
the most important nutritive ingre-
dents of the soil exist very largely in
combinations not otherwice sufficient
~ soluble to meet the demands of the
crop during the season OF rapid
growth. The importance Of this con-
dtion is still further enhanced by the
fact that even materials added to the
soil in the form of soluble fertilizers
are to a very considerable degree
transferred in the soil into forms not
soluble in soil waters.
- o,.l
fore, most important mineral soil con-
stituents are phosphoric acid and pot.
ash, and they are the ouly ones for
which crops must chiefly depend on
artificial supply. These two sub
stances, an acid and base, would
naturally unite to form phosphate of
potash. This is very soluable sub
stance and were nothing to interfere
by changing its character 1t would be
rapidly dissolved in the soil water and
be washed away faster than it could
be taken up by the plant; and thus
these indispensable plant nutriments
would be lost to the crop. Nature has
provided, however, that they undergo
a reconciliation in the soil, each unit
ing with the other soil constituents to
form insoluble compounds.
These latter, however, though not
readily dissolved by soil water are
chemically soluble and thus available
to the crop. The solvent secreted by
the roots is the most active agent in
effecting this result, and therefore IL
is clear that the dissolving power OF
the root is the most potent factor in
rendering soil ingredients available as
plant food. An equally important fact
is the truth that this same property is
indirectly responsible for the conser.
walton in the soil of the mineral food
ingredients till required by the crop,
instead Of passing away in the perco
latng water, the most important Of
which, potash, exists in quantities
hardly equal to even the present de-
mand.-Cor. Farm News.