Burlington weekly free press. [volume] (Burlington, Vt.) 1866-1928, 1917-08-09
TOMATO LEAF DISEASE,
Spray with Resin-ON Soap Added to
Bordeaux Mixture.

The addition of resin fish-oil soap to
Bordeaux mixture promises to control
tomato leaf-spot, although Bordeaux alone
has not prevented losses.
Plant-disease specialists in the Federal
Department of Agriculture describe the
leaf-spot disease as one which causes de-
foliation of the plants, greatly reduced
yields, and inferior fruit. Small circular
spots develop on the leaves and sometimes
on the stems. They first appear as tiny
dots, having dark or water-soaked APP
pearance. Gradually they enlarge and
turn brown, and the leaves shrivel and
drop, beginning at the base of the plant.
MAKING THE SOLUTIONS.
Bordeaux mixture is best prepared by
making stock solutions of the separate
ingredients. The copper sulphate should
be mixed in the proportions of gallon
of water, preferably soft water, to a
pound of the sulphate crystals and there
should be five gallons of this stock solution
for each acre of tomatoes to be sprayed.
The crystals should be dissolved in the
usual way by suspendng them in bur-
lap bag which touches the surface Of
the water; the solution should be we'll
stirred.
| The lime suspension or milk of lime. Is
also pound to a gallon, but only three
/
the copper solution. Thus. il there are
twenty gallons Of the copper solution there
would be only fifteen of the lime milk.
The lime should be slaked gradually by
pouring the water on in small quantities
| and at intervals until all has crumbled.
| Finally larger quantities are added with
constant stirring until the volume is COM
pleted If quicklime can not be had and
hydrated lime is available use many
pounds of the latter as of copper sulphate,
but do not increase the quantity of water.
Air-slaked lime must not be used
The resin fish-oil soap suspension Is
made with pound of soap to a gallon Of
water. AS with the lime, only three
fourths Of the quantity of water Is neces-
sary. Hot water will hasten the dissolving
Of the soap. To avoid the formation OF
troublesome Jumps the water must be add
ed slowly at first with constant stirring.
PREPARING THE MIXTURE.
For general commercial operations two
50-gallon barrels with outlets at the bot
tom are placed on a raised platform SO
their outlets will be higher than the top
Of the spray tank. To make 100 gallons
measure eight gallons of the copper-sul-
phate solution into one barrel and six
| gallons Of the milk Of lime into the
other. Add to each enough water to make
forty-seven gallons, stirring the contents
thoroughly, and then let the two solutions
run with equal rates into trough lead
ing to the spray tank. At the same time
add six gallons of the resin fsh-oil soap
solution very gradually and in small
stream through the spray-tank strainer
along with tine copper-lme mixture. The
copper sulphate and lime should be mixed
before the soap Is added.
| Notifications of the method may be
used for smaller quantities.
| APPLYING THE SPRAY.
A traction sprayer such as that en-
ployed in the spraying of potatoes may
be used except where the vines are too
large. There should be three nozzles for
each row, one to spray downward and two
on the sides spraying toward each other.
These lateral nozzles should be set low
and pointed slightly up to get the spray
on the under side of the leaves. Thor
ough spraying. repeated at from seven
to ten day intervals, is necessary for the
best results, and must be continued
through August When the plants are too
large for traction sprayer in the rows,
roadways should be opened and the spray.
ing continued with long lines of hose.