Clarksville weekly chronicle. (Clarksville, Tenn.) 1873-1890, 1877-07-14
LAND PLASTER FOR TOBACCO.

quested by Mr.. M. III. Clark to give
you what information l can about
the use and effects of land plaster on
tobacco. 1t should be sprinkled
over the leaves of the plants when
they are just spreading the hills, and
again about topping time, being
careful that some of the plaster is on
all the leaves. Use about one hum
dred pounds in both applications.
The first time it takes about one half
a teaspoonful, the second time nearly
a tablespoonful to the plant; put it
on with the fingers. If only one ap-
plication is made it should be about
topping time or soon after. 1t is
best to apply early in the morning
or late in the evening when there is
not much wind to blow it off and
when there is some dew to make it
stick. / have seen it applied in hot,
dry weather, when there was no dew
or moisture to make the chemical
changes in the plaster, and there
seemed to be no benefit; also heavy
rains soon after the plaster is put on
the tobacco is liable to wash so much
of it away as to do little good.
The effect of plaster is to give to-
bacco in the field a beautiful dark
green color the difference in row
can be seen from a distance. Closer
observation will show the leaves
hang heavier and lower. When
cured it is inclined to have a dark,
rich mahogany color. OF course the
color of cured tobacco depends some
what upon the process of firing, but
this is generally the color of tobacco
that has had plaster on it.
Repeated experiments show about
ten per cent. increase in weight in
my own crops. l suppose the supe-
riOr price on our market from the
better color and richer quality of the
tobacco would be at least one dollar
in the hundred. Land plaster seems
to increase in a very great degree all
the fine qualities that make Clarks-
vile tobacco famous all over the
world.
l have noticed that the worms are
not so bad on the parts of the field
where the plaster has been used, and
l suppose that the fly is frightened
off by the white plaster on the plants
or does not like the Odor of it. 1t
costs about 81 rs to 81 90 per sack
of 200 pounds. The sack is a good
wheat sack and worth about 80 or 40
cents, which makes the plaster cost
from 30 to rs cents to the acre of to-
bacco. Land plaster is so cheap that
it does not pay to adulterate it, and
1 have never bought a poor article
of it yet.
1 give you something scientific
from the American Farmer by the
pen of Mr.. L. H. McGinnis, of Shen-
andoah county, Virginia.:
"The peculiar effects of plaster
also are to be ascribed, chiefly, to its
sulphuric acid. Plaster is one of
natures happy combinations, not
only in the inherent value as plant
food of its own constituents, but in
its chemical results in administering
ammonia. Ammonia is the most
expensive Of all commercial man.
ures. 1t exists, however, in the soil
in various shapes, and in the atmOs-
phere, in the form of carbonate. In
the atmosphere it cannot exist as
pure ammonia, because it combines
with carbOnic acid. AS this carbon
ic acid gas exists in the air in far
greater abundance than ammonia,
the latter always occurs in cOmbina-
ton with it; that is, in the form of
carbonate Of ammonia. This, though
found only in minute quantities in
the atmosphere, occurs everywhere
near the earth and in the soil. Rains
deWs and SHOWS remove it from the
atmosphere to the soil. 1t is evolved
from heterogeneous organic bodies in
and on the soil, in the gaseous form,
and escapes unless arrested by chem
ical union with fixed substances.
Plaster and water decOmpOSe and
convert it into a nOn-VOlatile salt
called SUlphdte Of ammonia; that is,
if plaster, water, and carbonate of
ammonia come together, the result
is the decomposition of the plaster
and the carbonate of ammonia, and
the simultaneous formation of car
donate of lime and Sulphate of am
mOnia, The process may be des-
cribed as follows: The sulphuric
acid of the plaster abandOnS its en-
brace of lime, and Obeys a strong
er affinity by uniting with the am
mOnia of the other compound, form
ing sulphate of ammonia. This
frees the carbOnic acid (Of the carbo-
nate of ammOnia) in the presence of
the lime, which is extracted from
the sulphuric acid, and both the
lime and carbOnic acid being free,
unite and form carbonate of lime.
1t is a double decomposition, result
ing in the formation Of sulphate of
ammonia, and carbonate of lime,
out Of the constituents of plaster
and carbonate of ammonia.
This sulphate of ammonia is a
nOn-vOlatile salt, and, in the soil, en-
tiers slowly into solution administer
ing ammonia and sulphuric acid to
the plants. The carbonate of lime,
meeting carbOnic acid in the waters
of the soil, takes double proportion
of the acid, forming bicarbonate of
lime, which is soluble and supplies
the plants with lime. 1t is not Won
derful therefore, in the light of its
peculiar power over carbonate of
existing almost every
wherein the water and air of the
soil, and in the air above, that the
use of plaster is followed by charm
ing effects on the life and vigOr of
plants.
In view of its trifiing cost COM
pared with that of the substance it
prepares and administers to plants,
to say nothing of its own cOnstltu-
ents, it may be considered one of the
most economical fertilizers in use.
But it is only under the influence of
water that plaster fixes ammonia.
In the absence Of water, the effect
is the reverse.
Very truly,
L. b. Ross.
Near GAINESVILLE.
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