The Bridgeport evening farmer., 1911-08-17
WOOLLY MAPLE
LEAF SCALE
PhenacOcus AcericOla King

This insect was first studied at
Peoria, ILL.,, by Miss E. A. Smith, who
published an account Of the species
in the North American Entomologist
for 1880, page 70, under the name Of
PseudocOccus aceris Geoff., supposing
it to be identical with the European
species. In most Of the literature this
insect has been recorded under that
name. On further study it was found
to be different from the European spe-
cies, and was described and named by
Mr.. George B. King in 1902.
1t is now about five years since I
first observed this insect on the ma
pie street trees of New Haven though
the insect may have been present for
a much longer time. 1t has now be-
come quite a serious pest of the sug-
ar maple in Connecticut towns and
cities. L have seen it in many places
in New Haven, Hartford, Bridgeport
and South Norwalk.
On August I'd some maple leaves
were sent by a New Haven seed firm
with the statement that one of their
customers brought them in and asked
to know a remedy. The leaves came
from a place on Humphrey street,
and were seriously infested with the
woolly maple leaf scale. I visited the
place Immediately, and found sug-
ar maple of ten Or twelve inches in
trunk diameter, which was so thor
oughly infested that scarcely leaf
was free from the white masses Of
wax. Many leaves had already drop
ped. The upper portion of the trunk
was completely covered with larvae.
A leaf, showing larvae and waxy egg
masses, and piece of bark from the
trunk, showing larvae and male pu-
pae, all from this tree, are reproduced
on Plate VII Two other small trees
near by were also infested, though less
seriously.
EXPERIMENTS IN DESTROY
ING THIS PEST
The owner feared that the trees
would be killed, and wished to save
them if possible. At that time I had
treatment, and 1 recommended that
the trees be sprayed with ordinary
kerosine emulsion. This was done on
Aug. 4th, and the mixture contained
two gallons kerosene, one half pound
common hard soap and one gallon
of hot water as a stock solution, this
being diluted nine times before using.
A few days later 1 found that few
of the scales had been killed, but that
most of them had not been injured
by the spray. The owner informed me
that the spraying did no good.
These trees were sprayed the sec
ond time August 18th, using an emu1
sion containing more kerosene and
made up with a soft naptha soap
without hot water. Two gallons kero-
sene, one pound soap. one gallon wa
ter, were the Quantities used, the
whole being diluted five times before
applying This time the trees were
very thoroughly drenched, and the
spray was directed against the lower
sides of the leaves and upon the bark
of the trunk and branches where the
larvae were gathered in the crevices.
Even with this emulsion containing
more kerosene. and with the naptha
soap. it was a somewhat difficult
matter to moisten the egg masses on
account of the wax. The first spray
striking a leaf rolls off in small drops,
but if the nozzle is kept long enough
in one place the mass finally becomes
soaked with the emulsion.
A few days after this treatment the
trees were examined, and nearly all
of the insects appeared to be dead. A
few leaves only showed indications Of
having been injured slightly by the
spray.
After making these tests, I ran
across Professor Cooley's Notes on
Some Massachusetts Coccidae" in
which he states that in the cities OF
Springfield and Holyoke the authori
ties have found it necessary to adopt
comba tive measures to control this in
sect In Springfield the bark was
scraped during the winter and treated
with a concen trated whale oil soap
solution applied with whitewash
brushes. Although this seems to have
killed most of the insects, yet at the
end of the following summer they had
multiplied SO rapidly that the treat
ment was repeated the next winter.
The NAPLES of Holyoke were sprayed
with one pound of whale oil soap dis
solved in one gallon of water in Feb
ruary 1896, and for the next two years
the insects We're not sufficiently abun-
dant to require further treatment.
Enthusiastically the best remedial
treatment is a winter spray of pc
troleum, whale oil soap, or some of the
contact poisons which can be used in
much more concentrated form than
can be applied to the foliage. 1t is
difficult to combat this insect with
summer sprays. If kerosene emulsion
contains much more than Is per cent
ing the foliage, and if half this per-
centage of kerosene is employed it
will not destroy the scale.
DESCRIPTION, LIFE HIS
TORY AND HABITS. |
On the under sides of the leaves |
may be seen masses of white wax
mm- in length and somewhat less in
width Though varying greatly in
size) having a powdery and woolly |
appearance. In this mass we find |
the body of the living or dead female, |
and a large number of eggs. The adult |
female is light yellow in color, and is
about 5 NM, or one-fifth of an inch
long, bearing a number of spinnerets
and short spines on the upper surface |
of the body. The antennae are 9
jointed, the last joint being the long
est. The adult male has two wings, |
and is red in color.
Eggs are found throughout the |
waxy secretion, and are from 0.3 to
0.4 nm. in length and about half as
wide, and light yellow in color.
The larvae when first Matched oc-
cupy the under surface of the leaf,
though often found on both sides. The |
female is pale yellow. while the male
larva is reddish yellow. When ma
ture the males crawl about over the |
bark of the branches and trunk and |
transform to pupae in the crevices Of |
the rough bark. the adults emerging |
about two weeks later The maturing |
females forsake the leaves and crawl |
about on the bark, mate with the |
males, and later return to the leaves |
and settle upon the under surface. |
Soon after, the secretion of white !
wax is commnced, and eggs are de- |