Lincoln County leader. [volume] (Toledo, Lincoln County, Or.) 1893-1987, 1914-01-16
New Leaf RoIIina Pest.

oregon Agricultural COlleSe, COrVdl-
lis.-As though there were not already
enough pests to plague the Oregon
fruit grower, new species Of harm
full insects has been recorded by Pro-
fessor H. F. Wilson, entomologist of
the Oregon agricultural college. 1t is
the leaf roller that is known to scient-
lists as Archips argysophilia. The
larvae was first observed by Profes-
sor Wilson in 1911, but not until the
present season were all the stages
studied and connected.
"The insect has undoubtedly been
in Oregon for a long period of years."
says Professor Wilson, "and is now
found in various parts of the William
cite valley, and in the fruit growing
sections surrounding Hood River, The
Dalles and Mosier. This preliminary
report is made in order to meet the
demands for information concerning
small, greenish worm that causes
serious injury by eating out small Sec
tions of young fruit
"In Oregon the injury has not been
so extensive as in Colorado and New
L vi L hdfO OOoCIfCu IHO vac
feeding on the inside of the bud, often
destroying the tip of a shoot. AS the
leaves unfold, each larva confines it.
self to single leaf, one side of which
it rolls and fastens down with silken
threads. This serves as a nest. We
have not observed them feeding on
the fruit, but from the reports of grow
ers there seems little doubt that they
cause most of such fruit injury in
this state.
Eggs are deposited anywhere on
the bark in masses about one-fifth
inch square, which are then smeared
over with dark-colored substance
that blends them with the bark, max
| ing them almost indistinguishable
The masses vary in number from
20 to over $50, and the egg stage lasts
from June, when they are deposited
until April or May of the following
year.
"The larvae mature in the shells
sometime before they emerge, which
is generally during the first warm
weather after the buds begin to open
At the time of Matching they measure
about one-twentieth of an inch in
length and are of dirty yellow color
except the head, which is black They
are quite active from the first, and II
their nest is opened they quickly
wriggle out and hang suspended by a
silken thread.
"The mature larvae are about an
inch in length. The head is shining
black, with the first segment back OF
1t having a light green border. The
adjoining two-thirds of the body is
dark green, the remainder yellowish
green. The feet are glistening black
The last pro-legs and the last body
segment are yellow.
In the pupa stage the insect meas.
ures from three-eighths to one-half
inch in length, and is light brown, the
under side shaded with green. The
top of each abdominal segment is fit.
ted with two rows Of saw-like spines
that point backward. The middle
spines are quite prominent while the
terminal ones are not SO we'll deyel.
oped.
THE adult moth is dark rusty red
variegated with obscure silvery
patches, each front wing bearing two
bright spots. Some are darker than
others, and two adults that emerge
from the same egg-cluster may NOT
resemble each other in color at all
They emerge during June, the egg
masses being produced soon after
wards.
"An important control measure ir
Oregon is winter pruning, as most Of
the egg masses are formed on the
smaller branches and twigs. Enough
may remain to cause great damage
and spraying may become necessary
Arsenical sprays are less valuable fol
this than for most leaf-eating insects
and the treatment Of Professor c. P
|, Gillette, for Colorado conditions, II
recommended: Make a spraying an
plication Of good soluble oil shorti,
before the eggs hatch. Should thil
fail to kill the eggs, make two appli
!, cations OF an arsenical or Blacl
Leaf-40 spray"