The Wisconsin tobacco reporter. (Edgerton, Wis.) 1877-1950, 1911-06-09

To obtain sufficient amount of plant
food for the rapid development OF
plants on the normal soils of WiscOn-
sin, it is necessary to make heavy APP
plications of fertilizers Barnyard ma
nures should always be applied in the
fall, especially coarse, unfermented
manures. These may either be left on
the surface to allow the fall and early
spring rains to leach the plant food in
to the soil, or be plowed under in the
fall, which is preferable where the
addition of humus to the soil is desir-
able. Horse manure which is very we'll
composted can be applied in the spring
with good results. Coarse, uncOmpost-
ed manures are liable to set up fer
mentation in the soil which is injurious
to the developing plants. Some grow
ers have obtained excellent results in
the seed beds by using prepared or
mixed commercial fertilizers. These
have the disadvantage in that the nj
trogen, phosphorus and potassium are
added in fixed ratio, regardless of the
need of the particular soil to which it
is applied Experiments at the Wis
consin station have shown that little or
no benefit is derived from the applica-
ton of phosphorus and potassium to the
ordinary seed bed soils. Nitrogen APP
piled alone has giveu the best and most
economical results. 1t is advisable,
therefore, that the growers purchase
the unmixed commercial fertilizers, and
apply the Sodium nitrate alone. In
many cases on the poorer soils it may
be necessary to apply complete fer
tilizer, but this should be compared with
the results from the use of nitrates
alone.
Nitrate of soda may be worked into
the soil at the time of preparation of
the seed bed at the rate of about one
to two pounds per rod of bed. 1t is
put on to the best advantage, however,
after the plants are up and have start
ed to form their second pair of leaves.
Two or three pounds of nitrate is dis
solved in one barrel of water. This So
luton should be made to cover two rods
of the seed bed (bed six feet wide). 1t
is often advantageous to put this solu-
ton on in two applications, in which
case one barrel of the solution is made
to cover four rods of bed. The second
application may be put on in ten days
or two weeks after the first. Pure
water sprinkled on the plants before
and after the application will lessen
the danger of injury to the plant fol-
iage.
The control of weeds in the tobacco
seed bed furnishes usually the most
tedious work in the production of to-
bacco plants. For this reason the bed
should not be located in place in
which weeds are known to be bad, or
near where hay or straw stack has
recently stood. The application of
ia
also be avoided, as it usually contains
large amounts of weed seeds.
The rotting of young plants in the
beds is due to fungus disease COM
monty termed ''damping-off. This
trouble is brought on by an excess of
moisture, high temperature, thick SOW
ing. and poor ventilation. The direct
cause is the presence of the spores of
the disease in the soil when the bed is
made. For this reason a process which
would destroy the spores, such as ster
liking the bed, would get at the very
foundation of the trouble. The most
practicable prevention which suggests
itself is not to start seed bed where
the disease is known to occur. Various
methods of sterilizing the seed beds to
prevent this disease are recommended
where yearly infestations of this disease
occur.
Burning the seed bed and steam ster-
ilization have been used with success.
Formalin treatment has proved satisfac-
tory in some localities. 1t is thought
that spraying with potassium sulphide
Oliver of Sulphur) after the plants are
up would control this pest, but this has
not yielded favorable results at this
station. Microscopic study of the di-
sease has shown it to be caused by at
least two kinds of fungi which are es-
pecially different as regards their
spores. For this reason spray mix
ture which might control one form of
the disease, might be entirely inefficient
in controlling the other form.