The Leavenworth echo. [volume] (Leavenworth, Wash.) 1904-current, 1915-10-15
SOME OF THE INSECT PESTS
THAT BOTHER fRUITGROWERS
Federal Bureau Making Study of Best
Way to Combat the Enemies of
Fruit TreSS

during the tall, winter ana early spring
Certain destructive insects are held in
check only by spraying during the dor
mant period OF trees when stronger
washes may be used than when the
trees are in foliage. Many insects Of
the orchard spend the winter on the
trees in the egg, larval or pupal stage,
and their destruction in the course OF
pruning or other orchard work is prac-
ticable and is of much importance in
keeping them reduced.
Orchard scale insects as class are
best treated after the foliage has dropt
from the trees. This WORK may be
done in late fall, during the winter
when the temperature is above freezing,
or in the spring before the buds swell
to any extent. Spraying of apple, pear,
peach and other trees for the San Jose
scale with strong lime-sulphur or other
suitable wash is now very generally
practiced by orchardists, and many per-
sons owning but small number Of
fruit trees in the yard also regularly
spray the trees for the control of this
serious insect pest. Lime-sulphur con-
centrate is used in spraying for the San
Jose scale, and may be purchased Of
manufacturers or made at home. The
commercial article usually has density
of 80 to "a degrees as registered on a
Baume hydrometer, and in preparing
the concentrate at home effort should
be made to secure a wash of about this
density. Such concentrate is used
at about the rate of one part to or 9
parts of water. Only one treatment
each winter is necessary to hold this
pest in subsection, but the application
must be very thoro, coating all parts OF
the twigs, limbs and branches. This
work requires spray pump, and these
may now be obtained for work on
almost any scale and range in size from
the so called bucket pump suitable for
work on a few trees in the yard to the
large gasoline power outfits employed
in extensive orchards. More specific
information on the San Jose scale and
the preparation at home Of lime-sulphur
concentrate will be found in Farmers
Bulletin $50.
Certain other scale insect pests which
may be present on the trees-the cher
ry scale, oystershell scale, etc, are also
pretty we'll held in check by this an
nual treatment with lime-sulphur wash.
This treatment is also effective against
the pear-leaf blister mite, which is uni
versally present on pears and in some
localities is very serious apple pest.
Certain destructive apple tree lice win
ter in the egg stage on the apple, es-
pecially on the newer growth, and thru
lime-sulphur spraying for the San Jose
scale undoubtedly results in the de-
struction of many of these eggs, tho
the treatment is not always sufficient to
obviate spraying after the insects have
Matched and the foliage is putting out.
Spring spraying Of peach trees when
the buds are swelling, in addition to its
destructive action on the scale insects
mentioned, is also an effective check
to the so called peach twig-borer, or
peach worm, which is very destructive
in California and numerous arid valleys
in the west. This spring application
of lime sulphur to peach is practically a
specific for the serious fungous disease
known as peach-leaf curl. In some
sections of the country the pear Psylla
is very serious pest to pears. The
adults hibernate in crevices and cracks
on the trees, resuming activity with the
first warm days in the spring. Spring
spraying Of pears for the San Jose scale
has in addition a very marked value in
checking the pear Psylla.
The socalled terrapin scale Of peach,
as we'll as Lecanium scales in general,
are not satisfactorily controlled by the
lime-sulphur spray, but should be dosed
with strong kerosene emulsion, or with
a mixable oil. This latter is general
term applied to several commercial
preparations which are used at the rate
of one part to Is or 20 parts Of water.
In addition to routine dormant-tree
spraying much good work may be done
in the control of orchard insects by op-
erations during the leahess period. The