Audubon County journal. (Exira, Iowa) 1884-1993, 1918-04-11

THOROUGH APPLlcATlc
prepared by the United States Depart
ment of Agriculture.)
The spraying of trees during winter
and spring, or when they are in a DOR
mant condition, Is directed largely
against scale insects, especially the
San Jose scale. There are two prin-
cipal advantages in spraying at this
time: az The absence of foliage per-
mits Of more thorough applications,
and ~ the sprays may be used much
stronger than during the growing
season. Contact sprays are employed,
as lime-sulphur solution, fish-oil and
other soap washes, kerosene and crude
petroleum emulsions, miscible oils, and
the like. The prime essential is thor
oughness in making applications, so as
to cover every part of the tree. because
I'm general only those insects actually
hit with the spray are killed.
Applications may be made In late
fall as soon as most of the leaves have
fallen, at favorable times during the
winter when the temperature Is above
the freezing point, or, preferably, In
the spring shortly before the buds are
due to swell. There is probably less
danger to fruit buds and twigs from the
iuse Of sprays in the spring than at 9th
Ter times. Better results follow spray
Ing with lime-sulphur solution in late
spring than in late fall or during the
winter, since this insures some spray
on the trees during early summer,
which is Of value in killing any young
scales, the offspring Of adults, which
may have escaped destruction.
Important Orchard Work.
Spraying dormant trees for the San
Jose and other scales and for other in
sect pests has come to be very inl-
portant part Of orchard work, especial
~ in the East and on the Pacific slope,
and in general it is possible so to time
this work that a single application will
reach most of the troubles comfortable
by dormant-tree sprays. Other things
being equal, the insecticide having the
greatest range Of usefulness should be
|employed. OF the several dormant
tree sprays, the standard lime-sulphur
solution Is the one most generally used
against the San Jose scale, and 1t Is
equally effective against several other
insects which may coexist on the trees.
1t Is an excellent fungicide, and, aside
from the inconvenience experienced in
Tits preparation and its disagreeable
character, 1t furnishes an ideal spray
for dormant trees. Abundant expert
ence has shown it to be an effective
remedy in the control Of the San Jose
scale under all conditions, and for most
other diaspine scales, as the cherry
scale, the European fruit scale, and
reasonably so against the oyster-shell
Iscale and the scurfy scale. Lecanium
Scales such as the terrapin scale and
the brown apricot scale, are more eff
fectively controlled by mneral-oil
sprays. The thorough treatment
each year, therefore, with lime
sulphur solution win keep well under
control the more important scale-in-
|sect pests of the orchard.
There are certain other troubles con-
Itrolled by the dormant-tree sprayings
with sulphur solution. It has been
found effective In destroying eggs Of
/ THE pear-tree psylla and has long been
known as effective against the pear
leaf blister mite. The red spider and
lleggs Of the clover mite and other
mites are probably also destroyed. In
I california, If applied in late spring, the
lime-sulphur solution has been found
effective In destroying the peach twig-
borer. Entomologists are not agreed
as to the benefit from lime-sulphur
spraying in the destruction of eggs Of
apple aphids, and other plant lice, but
Its value in this connection is perhaps
not important. In practice, therefore,
! the plan should be to make one thor
ough application Of lime-sulphur solu-
| ton to orchards each spring as gen
eral treatment for the control not only
| of the San Jose scale but of mi "
other scale insects and other pests.
| Homemade Concentrates.
| Several years ago the cooked lime
| sulphur wash was used largely for the
control of the San Jose scale but has
now been generally superseded by the
| commercial or homemade concentrates.
Since inquiry occasionally is received
lbs to its preparation, the formula and
/ method Of making are given below:
! Stone lime. pounds .................20 or 2
! Sulphur Commercial ground).
| pounds OBSERVATION-DISCLOSURES. 10 or ~!
| Water to make .............".......6o or