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Fig. 20. Forbes or Cherry Scale, (a) Young scale, light colored, with central nipple but
no circular groove * (b) adult female scale with central or nearly central, orange-
colored nipple, and gray outer margin of scale; (c) male scale, showing the oval
shape, and nipple near one end. The body of the insect is under the scale.

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The life history of this scale is said to be as follows : It passes the win-
ter in a partly grown stage. The males emerge about the end of April. In
May the young begin to come forth and eggs and young may both be found
up to about July. There are two broods in some of the American States, but
whether there is more than one in Ontario has not yet been discovered.

The Cherry scale has been found in Ontario at Ottawa, London, St.
Catharines, Orimsby, and in Prince Edward county.

The host plants so far discovered are cherry, apple, hawthorn, fragrant
currant, and beech.

•Remedies :

The same remedies should be used as for the San Jos6 scale.

Natural Enemiei :

Several species of Chalcid flies are said to attack it, also a tiny white
mite, and the twice-stabbed ladybird beetle (Chilocorut bivulnerus, Muls.)

The English Walnut Scale (Aspidiotus juglans-regice, Comst.) Figs. 21
and 22.

Fig. 21. The .English Walnut Scale (Aspiodioius juglans-reOice). (a) Female scale; (b)
male scale: (c) male chrysalis; (d) male scales on twig; (e) female scales on twig.
a, 5, c, enlarged; d, e, natural size. After Howard. From U.S. Dep. Agr., Year
Book for 1894.

Fio. 22. Anal plate of English Walnut Scale, showing the large median lobes, and
notched outer margin of second lobe.

The English Walnut scale has been found in Ontario in only two or
three localities, although it probably exists in several others. If some sam-

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pies from CoUingwood, sent by this department to Washington, and thought
by the authorities there to belong to this species, should prove to be really
such, the scale is capable of doing great injury to the trees it attacks. The
poplars and willows at* CoUingwood on which it was found were very thickly
covered, and were dying, apparently from the effects of the scale.

The adult female scale is larger than any other species of Aspidiotus
described in this paper, averaging almost 3 mm. in diameter. It is circu-
lar or nearly circiilar in outline, very flat for its size, resembles closely the
color of the bark it is on, being usually a pale grayish brown. The exuviae are
usually eccentric and are orange or reddish in color, though often this color
is partly concealed by a waxy secretion.

Though the adult female of this scale is easily distinguished from the
San Jose by its large size and reddish eccentric exuviae, yet the winter stage
of some specimens we have received is with great difficulty distinguished
from the winter stage of the San Jose. The chief points of distinction seem
to be : (1) The winter stage of the Walnut scale is a little larger than that of
the San Jos^; (2) Even in these winter, scales, the reddish exuviae can often
be seen with the aid of a lens although a waxy secretion almost conceals it.
In the San Jose scale this reddish color does not appear.

We have very little knowledge of the life-history of this scale. From
specimens, we have seen this autumn it seems to pass the winter for the most
part in an immature stage. It does not bring forth its young alive but lays
eggs. There is probably more than one brood in a season.

The scale has been found only at Grimsby and CoUingwood (?)

The host plants so far discovered in Ontario are apple, willow and

Remedies :

The same remedies should be used as for the San Jos^ scale.

We have not been able to observe what natural enemies this scale has.

The Putnam Scale, Aspidiotus ancylus, (Put.) Fig. 23.

Fio. 23. Anal plate of the Putnam Scale, showing the unequal thickenings in first
incision, the rudimentary second lohe, and the wide interval hetween median and
second lobes.

The Putnam scale is distributed fairly widely throughout Ontario. It
has not, however, been known to do much damage in the province although
in some of the states across the boundary it is said to have been quite de*

The adult female scale is usually more nearly oblong than ciraular,
about 1.5 mm. long, 1-1.3 mm. wide, and slightly convex. The general
color is greyish black, varying somewhat with the color of the bark it is
on. The exuvi&l part is eccentric and practically always red or reddish.
Sometimes this red color is obscured by a whitish film which can easily be
rubbed off.

This scale can be easily distinguished from the San Jos6 by its oblong
shape and the red eccentric exuviee. It has the peculiarity of producing
in a small degree the purplish color so characteristic of the San Jose scale.

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It passes the winter in a nearly full grown stage. The males begin
to appear, it is said, in May. In late spring or early in summer the female
lays from 30 to 40 eggs. These hatch in July. There is only one brood
in a season.

The scale has been reported from Ottawa, Toronto, Belleville, St. Cath-
a^nes, and Kingsville.

It has been found on plum, elm, and willow in Ontario, but is said to at-
tack also cherry, apple, red currant, maple, oak, ash, and beech.
Remedies :

The same remedies should be used for this scale as for San Jose.

Parasites :

The only parasite we have heard of as attacking it is a minute Chalcid
fly, Coccophagus varicornis, (How.)

Osbom's Scale (Aspidiotus Osborni).

Osbom's scale is found on forest trees in northern and western On-

The mature female is about the same size as the Curtis scale, averaging
about 2 mm. in diameter. It is very smooth and circular, and the exuviae
is eccentric. The general color is brown, varying somewhat with the color
of the bark of the host; under the loose bark of the paper birch the color is

It has been found on paper birch, yellow birch, cottonwood, and white

It passes the winter in a nearly full grown stage.

Parasites :

The work of Chalcis flies have been found on several occasions.

The New York Plum Scale, Eulecanium cerasifex (Fitch.) Fig. 24.

The New York Plum Scale has become one of our most common scales
and like the Oyster-shell scale has spread over practically the whole prov-
ince. Though not so destructive as the Oyster-shell, it is often quite in-
jurious where abundant and sometimes kills the infested tree.

The scale is one of our largest species. The mature female is nearly
hemispherical, but usually a little longer than broad, being 3-5 mm. and
2.5-4 mm. wide. It varies in color from light brown to almost black. The
surface is usually glossy with, however, numerous little depressions and ele-
vations which sometimes take the form of grooves and ridges radiating from
the apex to the base.

The male scale is very unlike the female in shape, size and color. It
is elongated in form, 2-2.5 mm. long, and 1 mm. wide, only slightly convex,
and is grayish white in color. Both male and female scales are found
near each other on the same branch.

The winter is passed by both sexes in the half -grown stage. The winged
males appear June 1st (this year, 1907, it was June 12th), and soon after
this the females lay their eggs and die, but their dead body still remains
as a cover for the ^f^g mass. About the end of June (this year on July 19th),
.the eggs begin to hatch out. There are sometimes about 1,000 eggs laid by
a single scale. The young scales move from the branches to the leaves
where they remain until autumn and then migrate back to the branches for
the winter. There is only one generation in a year.

We have found this scale on a great range of trees and other plants at
Ghielph, the following being the list as observed up to date of writing : —
apple, plum, pear, mountain ash, hawthorn, currants, gooseberry, wild red

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Fio. 24. Twig of plum infested with Lecanium or New York Plum Scale, ^(o) The old
scale of the previous summer empty and lifeless; (h) the immature wintering
scales, which will become full grown like (a) next June.

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Plate A.

1. Cecidomyia ulmi, Beuten. 6.

2. Lasloptera coral, Felt. 7.

a. Cecidomyia balaamifera, Llntner. 8.

4. Hormomyla cratisflrlfolia. Felt. 9. Rnabdoohfura nnHnina WaIaH

Chorlstoneura flavolunata, Fe>lT> t

Rhabdophaga batatas, 0.8... i tOOQlC
Affromyza feneiventrlR, Fallen. O

Plate B.

1. Rhoditessp. onBlacky>erry. 4. AndricuB fu tills, 0.8.

2. DiastrophuH turgidus, Bass. 5. Diastrophus potentillFe. Bass.

3. RhoditesmultispinosuK, Gill. 6. Neuroterus umbilicatas, Boss.

uiyiLi/iKU uy -^^j >^^


Plate 0.

1. AndricuB punctAtns, Baas.

2 . Blorhlza forticornis, Walsh .
t. AndricuB davula, Ba«.
4. Cvnimatrobilana. O 6. 8. pemnhiiim«iiinrii-*"o-

5. Andrlcus paplllatus Q ^., CloOQle

6. Andrlciis topiariuB, Aihra. JVv'Vv'pilv^

7. Eucosma scudderiana, Clem. *^

Plate D.

1. Erlophyes sp., Amelanchier Canadensis.

2. Eriophyea sp., Juglans nigra.

3. Eriophyes sp., Populus italica.

4. Krfophyes'sp.. Vitia cordifolia.

6. Erlophyes sp., Snlix fraeilis.

6. Young Oyster-shell scalea parasitized

by a fungus.

7. Curtis scale parasitized by a fungus.

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Parasites :

(1) A fungus disease (Cordyceps clavulata), attacks and
of the scalels.

(2) At least 3 ehalcid flies, Pachyneuron altiscuta (I
lividus (Ashm,), and Coccophagus cognatus (How.)

(3) Several species of lady-bird beetles.

(4) A large flesh-colored species of larva was found feedi
but we were not able to rear the adults.

The Terrapin Scale, Eulecanium nigrofasciatum (Perg.)

This scale was first discovered in Ontario in 1901 at St. C
to the present time it has been reported to us only from
Walkerville, and Windsor. In each case the infested twigs
taken from maple trees and these were literally covered witl
is clear from such specimens that a badly infested tree woul
so the scale is one to be guarded against. Mr. Sanders of
Entomology, Washington, in his circular No. 88, says that
be considered a "dangerous pest."

The easiest time to recognize this scale is in the winter
season it is considerably smaller than the New York Plum sea
cerasifex, which, even when mature, it never equals in size,
general shape as this well known scale, being nearly hemis]
about 2 mm. in length and slightly less in width. Along i]
longitudinally is a reddish streak or stripe about 1 mm. loi
wide. The rest of the surface is usually mottled red and
forming the ground, so to speak, and black stripes radii
reddish top to the base. Sometimes the black forms a belt ai
extending from the red boss or crown nearly to the base, i
often a red margin in such cases. Not uncommonly a seal
entirely, red or on the contrary almost entirely black. Whei
is still, the same general color and shape but there is an ii
the scple now being 3-3.5 mm. long and somewhat less thf
Later in the season the color fades.

A peculiarity, at least, of the winter stage of the seal
punctured or crushed, a reddish liquid exudes from the wou

The eggs are laid in the spring and hatch about the en(
August the tiny winged males emerge and consequently t
females are fertilized the same season.

Although only maple trees have been reported to us as
up to the present time in Ontario, yet we find that in the TJi
scale infests not only these but ^Iso the peach, plum, apple
hawthorn, and several other trees. Hence it is clear thai
should be on their guard against it.

Remedies :

The lime-sulphur wash has proved a failure in the cas<
and the most satisfactory remedy so far discovered is to spray
fully when the leaves are off with kerosene emulsion of abou
strength. Care should be taken to prevent the emulsion run
trunk and getting to the roots which it would probably injure,
or early spring before the buds begin to burst would be the
spray. While this is practically the only spray recomraende
scale insect," some very able entomologists doubt whether even
like so successful as its advocates claim. Seeing that there is
about the effectiveness of washes and that the scale is capable

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damage, the proper course to take is to be on one's guard against allowing
it to get a footing and, if a tree should be found to be infested, cut it down
and bum it at once, thus taking no risks.
Parasites :

This scale like almost all the rest has its insect foes, a tiny chalcid fly
of the genus Coccophagus has been found to attack it. A fungus parasite
known as Cordyceps clavulata is not uncommon on this scale.

Eulecanium carya:, (Fitch).

Eulecanium caryce is said to be the largest known species of Euleca-
nium. It has been in Ontario for at least ten years, having been discovered
by Dr. Fletcher in the Niagara district in 1898. Judging from the fact that
it has been found in that district and that we have discovered it at Ouelph
on several trees in the forest, it probably occurs at least all over the south-
western part of Ontario. From our own experience and that of others we
believe that the scale is very seldom abundant on any tree; in every case
where /we discovered mature scales {here were only two or three at
most, and often only one specimen to be found on a branch (always on the
under side). Consequently the scale is seldom sufficiently injurious to cause
any alarm.

It is easily identified by its large size, being more than twice as large
as the New York Plum scale (Eulecanium cerasifex). Like this scale Eule-
canium caryae is more or less hemispherical in shape. It is 7-10 mm. long,
6-9 mm. broad, and 3-4 mm. high. The surface is glossy, light brown to
black in color, and covered with a fine powder. On all the specimens a keel-
like structure ran longitudinally from end to end through the centre. The
rest of the surface was more or less rugose. In some cases we could see
fine (including the keel-like structure), nearly parallel longitudinal ridges;
in others these ridges, except the keel, were not perceptible.

We have not yet traced out the life history of the scale, but from ob-
servations made believe that it is probably very similar to that of the New
York Plum scale; that id, it passes the winter in the nearly mature stage,
the males emerge in late spring; the eggs, which are very numerous and
white in color, hatch out in July; the young migrate to the leaves and re-
migrate to the branches in the autumn.

This scale has been found at Guelph on the hawthorn and American
elm, and at St. Catharines on the peach.
Remedies :

Seldom any need be applied, but the same remedies as are used for the
New York Plum scale should destroy this one.
Parasites :

There is a very little doubt that the failure of this scale, laying as it
does a very large number of eggs, to increase rapidly is to a great extent due
to the attacks of parasites. Dr. L. 0. Howard informs us that a chalcid,
Chiloneurus albicomis, (How.) attacks it. (Bull, vii, N. S. Div. Ent. V.
S. Dept. Agr. 1897, p. 63). This is one of probably a considerable number
of parasites.

Kermes pubescens (Bogue).

Kermes pubescens is a large scale resembling the New York plum
scale and other Eulecanium scales, but differing in external appearances
chiefly in being more nearly spherical. It has been found by us at Guelph,
Toronto, and Perth, hence is probably wide spread over the province. Only
oak trees are attacked, as it was found in abundance on each infested tree
it must do considerable injury. Mr. Bogue, who discovered^ and named the
scale, reports it as attacking the young twigs and leaves, but we have always

5a EN r^ T

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found it in the cracks of the bark on the trunk and branches and have not
yet observed it on very young twigs or on leaves.

The mature female scale is nearly spherical as a rule in shape, though
often it seems to be modified in form by its position in the cracks or fissures
of the bark.. It is 3-4 mm. long, 3 mm. high, varies in color from light to
dark brown, often mottled with black, is shiny in appearance and covered
with a short white pubescence.

The male scale resembles very much the male of the New York Plum
scale. It is, however, whiter, being snow-white. In shape it is oblong,
2 mm. in length, 1 mm. in width and fairly convex.

The winter is passed by both sexes in the nearly mature stage. The
males en^erge about the first of June or a little earlier. This year '07 the
season was late and they were observed coming forth June 12th. Though
the females are fertilized shortly after this we have not yet had opportu-
nity to discover the date when the eggs hatch.

Remedies :

(1) Kerosene emulsion 25 per cent, put on when the trees are dormant
should kill the scale. The tree must be soaked, however, to ensure the spray
getting into the crevices of the bark where the scales are.

Parasites :

A considerable number of the scales observed had been perforated, evi-
dently the work of a small chalcid fly.

The Cottony Maple Scale, Pulvinaria vitis (L.).

The Cottony Maple Scale is by no means a stranger in Ontario. It is
found all over the western part of the province at least, and probably over
much of the remaining parts also. As the name indicates, it attacks the maple
chiefly, and in cities often does much damage to maple shade trees. It is,
however, rarely abundant for many seasons in succession, because of the
attacks of parasites.

The scale is most easily identified in spring or early summer. At this
time of the year it appears as a brown, elliptical, convex insect, with so large
a cottony-like egg-mass protruding from behind and beneath that the scale
seems to be standing on its head, or nearly so. The egg mass and scale to-
gether are about 1 cm. long, the scale itself being about 1-3 of this length.
The cottony egg-mass has given the scale its name and makes its identifica-
tion easy.

The young lice hatch about the middle of June usually, the hatching
period extending over a couple of weeks. The tiny insects at once migrate
to the underside of the leaf, though some also establish themselves on the
upper surface. On the leaves they usually arrange themselves alongside the
midrib and veins. About the end of August the winged mates emerge and
fertilize the females. A few weeks later the females desert the leaves and go
back to the branches, where they pass the winter. In the spring of the year
they rapidly swell, and in early summer form the cottony mass and lay their
eggs in it. Hence there is but one generation in a year.

Although the maple trees are the ones most commonly attacked, the scale
is found on many other trees as well. It has been found at Guelph on the
following maples : Acer saccharum, A. rfaccharinum, A. nigrum, A. rubrum,
and A. negundo; also on basswood, American elm, hawthorn, white poplar
(Populus alba), scrub willow, red-osier, dogwood, ilex (verticillata). Spiraea
(salicifolia) and grape vines.

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Except in towns there is very little need of using any remedy be-
cause parasites keep the scale well in check and, as mentioned above, it is
seldom bad many years in succession. In towns, await the hatching of the
young, and shortly afterwards prune severely, and where valuable trees are
attacked spray these thoroughly with kerosene emulsion, flour kerosene or
whale-oil soap. More than one spraying will probably be necessary.

The Oyster-shell Scale, Lepidosaphes ulmi, (Linn.) Fig. 25.

The Oyster-shell scale is found in almost every district in Ontario, and is
doing more injury to the fruit trees of the province as a whole than any other

The scale can easily be recognized even without the aid of a lens. It is
2.5-4 mm. long, and .75-1 mm. wide in the broadest part, tapers toward the
the end, is shaped like a diminutive oysier-shell, and closely resembles in
color the bark on which it is found. The small end, or exuvia, is usually
much lighter in color than the rest. The male scale differs from the female
chiefly in being considerably smaller and broader in proportion to its length.

It passes the winter in the egg stage, from 20-100 eggs being concealed
under the covering of a single scale. The eggs hatch about the first week
in June. The tiny, white, young scale insects run about for a day or two on
the bark or leaves and then insert their sucking tubes in some chosen spot
from which they never move during the rest of their life. There is only
one brood in a season, but even so, the scales increase very rapidly where no
attempt is made to keep them in check. Badly infested trees become much
weakened and often die.

Not only does this scale attack apple, pear, plum, and cherry trees, but
it also attacks currants, gooseberries, rose bushes, spirieas, lilacs, and num-
erous shade and forest trees, such as the mountain-ash, hawthorn, red-osier
dogwood, black and white ash, American aspen, prickly ash, mulberry, and


There are several remedies that can be used with success in combating
it: —

(1) Spray with kerosene emulsion, flour kerosene, or whale-oil soap dur-
ing June as soon as all the eggs seem \o have hatched. This date can easily
be ascertained by examining carefully, even with the naked eye, a few infested
branches. These remedies are the most popular.

(2) The lime-sulphur wash. This remedy, though not so popular as
No. 1, has given excellent results when well made and carefully put on late
in the spring when the buds are well swollen or are opening.

(3) Whitewash. The trees must be sprayed twice, with an interval of
a few days between, with whitewash. This should be done as soon as the
leaves fall in the autumn. . Use 1 to 2 lbs. lime to 1 gal. water.

Parasites. — ^The most common parasites are : (1) A tiny little mite, probably
Tyroglyphus maluSf that preys both upon the adult and the eggs; (2) a small,
yellowish chalcid fly, probably Aphelinus mytilaspidis, Le Baron, the larva
of which preys upon the eggs (scales perforated by small, round holes have
been parasitised by this kind of insect) ; (3) certain species of ladybird beetles,
especially the twice-stabbed lady beetle (Chilocorus bivulnerus) Muls. This
year we found a pink fungus attacking the young scales, and on a mountain
ash tree, in Toronto, which was covered with scales, the pink fungus para-
sitised and killed nearly all the scales on the tree. (See Plate D. Pig. 6.).

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Fio. 25. Oyftter-shell fiarklouse (Lepidosaphes ulmi). (a) Adult female, back view,
showing the two moulted skina at anterior end, and the bristles of the sucking
tube; (b) adult female turned over, showing the insect at the anterior end and the
eg^ at the posterior end: (c) adult male scale, much smaller than female^ with one
moulted skin at anterior end.

The Scurfy Scale, Chionaspis furfura, (Fitch). Figs. 26 and 27.

The Scurfy Scale, though widely distributed throughout Ontario, is-
seldom found in so great abundance as the Oyster-shell. Badly infested
trees or other plants are very much weakened and not infrequently die as a

The mature female scale is somewhat of the shape of the Oyster-shelly
but is much broader in proportion to its length, and is more properly describ-
ed as pear-shaped, being 2-3 mm. long, 1-2 mm. wide in the broadest part
and tapering rapidly to a fine point at one end. It is very slightly convex
and is grayish white in color. The scurfy appearance which it gives to a
badly infested branch or twig has evidently been the cause of its receiving
its present popular name.

The male scale is very different from the female. It is elongate in shape,
is only about 1-3 the length of the female, is whiter in color and has three
parallel longitudinal ridges on its back (tricarinate).

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Tlie Scurfy Scale has a very similar life history to the Oyster-shell. It
passes the winter in the egg stage, there being from 20-80 purplish red eggs
under a single scale covering. About the first of June these hatch into tiny
orange or reddish brown larvae, which run about freely for a few hours, and
then in some favourable place insert their sucking tube, or proboscis, into

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