The sun., 1918-11-17
HOW TO CONTROL SAN JOSE
SCALE.


San Jose scale will bring about the
death OF most fruit trees and many
ornamental and shade trees. Its DIS
covery therefore shoAld be followed
by prompt measured OF control;
whether In commercial orchards or
private grounds. Private individuals
will scarcely feel disposed to equip
with such expensive apparatus as
orchariists may find profitable.
Where only few plants are In
! tested It IS probably better for the
owner to use some OF the prepared
washes. In fact. many commercial
orchardists prefer to use these in pref
erence TO making them a. home. These
consist of compounds of sulphur in q
highly concentrated condition, or pow
ders, 10 which II Is only necessary 20
add a sufficient quantity OF water.
The powders are much more con-
venient to handle and store than
the commercial iime-sulphur coneen-
trates. The latter, however, are still
largely used by orchardists a'ho do
not care 10 incur the expense OF con-
structirg the cooking plant 10 make
their own lime sulphur washes.
Prepared in one way or another
some form Of lime sulphur wash is the
most common agent for controlling
this scale. A formula much in use !s:
sulphur taour or Gowers). .......l5 pounds
water TO make. ................,5 so gallons
In preparing this wash about one
third OF the total quantitv of water
required is heated in a cooking barrel
or vessel: the lime then added and the
sulphur Immediately afterward. The
sulphur should previously. however
have been made into q thick paste
With water. After the lime has slaked.
about another third .: tile water
should be added and the cokinz cor.
unued for an hour, when the rest OF
the water IS put In. During the time
or cooking stirring is necessary II the1
wash is cooked in kettles. It must also
be strained as it is run into the spray
tank
Comparatively few fruit growers
now employ this method, because this
wash must be applied Immediately
after It IS cooked, otherwise there Is
crysta,lization Of the sulphur and hard
dening OF the sediment upon cooling
The cooking is also inconvenlent. II
IS fer these reasons that rlauutactur-
ers put on the market concentrated
solutions OF lime sulphur already men
toned and which when used at prope-
strength are quite as satisfactory as
the old time formula.
When lime-sulphur concentrates are
made at home the so-calied 50-l00-5O
formula IS frequently used. This is
composed Of so pounds OF lime 100
Mound OF sulphur, and water 70 make
on gallons, the respective ingredients
being boiled together for from ifty
minutes 20 an hour, while the nixturA
Is vigorously stirred either by hand
or by mechanical agitator. As soon
as the cooking Is over the solution
should be drawn OF and run through
A 80 mesh strainer into barrels. the
agitation being continued all this tins
III order 10 effect an equal distribution
or the sludge. When properl,. stirred
this solution can be kept for a year or
more before being used. Such cor
centrates vary considerably in strength.
and Il ls important that they bs tested
with hydrometer
In controlling the scale il Is aITavs
advisable 10 spray the trees while I'm n
dormant condition, for at this time the
wash may be used much stronger than
would De saIe TO use on foliage. Spray
ing may be done in the fall In mild eli
mates during the winter, or preferable
IN cary spring before the buds push
out. For small plants. low trees. orns-
mental hedges, &c, bucket pump or
knapsach pump vii, provide ali the
apparatus necessary. For orchards oc
some SIZE, as five 10 ten acres, bar
rel or hand power pump vii, prove
more satisfactory, and for large COM
nnerciaI orchards sasoiene outfits are
usually employed. Where only one or
two trees are 10 be treated It 10 quite
practicable to apply the wash on the
limos and branches with a brush.
In addition 10 the lime sulphur
washes Kerosene and crude petroleum
In emulsions may be used. Kerosene
and crude petroleum may be readily
Hmu'sired in soap and the oil thus used
at any desired strength. The so-called
'miscible oils" however, which are
commercial preparations, are now
largely used by those requiring oil
sprays in preference to the homo made