56 
March, 1890. 
ORCHARD 
Conducted by A. B. CORdlet, 
Agricultural College, Michigan. 
The Strawberry Leaf-beetle. 
( Paria aterrima Oliv. and Scelodonta nebulosus See.) 
One of the first insects to require our at- 
tention in early Spring is the Strawberry 
Leaf -beetle. Paria aterrima Oliv. The bee- 
tles pass the winter in the mature form and 
the first warm days bring them forth with 
appetites sharpened by a winter's fast, to 
feed upon the just starting strawberry 
leaves. In the vi- 
cinity of Lansing, 
Mich., they have 
been found as ear- 
ly as March and in 
April and May 
have been so num- 
erous as to com- 
pletely def o 1 i a t e 
and ruin the vines. 
Farther south, for 
this insect is com- Fig. 265. 
mon from Massachusetts to California 
and from Michigan to the Southern States, 
it probably appears even earlier than this. 
The beetle (see Fig. 265, after Forbes) be- 
longs to the Chrysomelida?, the same fami- 
ly lo which the Colorado Potato Beetle, the 
Grape-vine and Cabbage Flea -beetles and 
many others of our most troublesome bee- 
tles belong. It is about one-eighth of an 
inch long, and varies in color from yellow- 
ish or brown to shining black. The head, 
antenna? and legs are always yellowish. In 
the lighter specimens the vential segments 
of the abdomen and two spots on each wing 
cover are black. The mature insects con- 
tinue to feed upon the foliage of the straw- 
berry or raspberry until late in May or early 
in June, when they deposit their eggs, prob- 
ably in the ground, and disappear. He who 
dreams that their injurious work is finished, 
however, will receive a sad awakening. 
Frequently the first evidence one has to the 
contrary, is the death of the vines in patch- 
es here and there throughout the field, aV 
though a close observer will probably no 
tice the dwarfed appearance ot the vines 
before the injury has become so serious. 
The eggs deposited in May or June hatch in 
July and from then until the middle of Au- 
gust countless numbers of small white 
grubs may be found feeding upon the roots. 
Here the injury done by them no doubt 
equals or exceeds that inflicted by the ma- 
ture beetle in feeding upon the leaves, and 
is even greater than that produced by the 
crown-borer, Tylo- 
dirma frag aria. 
The first attentions 
of the larvae seems , 
to be confined to 
the smaller roots, fig. 264. 
but later they also freely gnaw and penetrate 
the main root, occasionally perforating it 
from side to side in different directions. 
Prof. Forbes says: “Ihave seen roots of 
strawberries, from fields infested by these 
larvae, which looked as if they had been 
riddled with fine shot.” 
The larvae (see Fig. 264, after Forbes) 
are small, white, six-legged grubs, from one- 
eighth to one-fifth of an inch long, with yel- 
lowish head and brown jaws. They are 
easily mistaken for the Crown-borer, Tylo- 
derma frag aria, or for tbe young grubs of 
the May-beetle. Laehnosterna fusca, but can 
be distinguished from the former by pos- 
sessing three pairs of thoracic legs, and 
from the latter by having a relatively short- 
er, thicker body, and by not being so much 
arched. The root-worms are only about 
twice as long as broad, while young grubs 
of the May-beetle of the same size, are four 
or five times as long as broad. In July and 
August the larvae transform to pupae, (see 
Fig. 266. after Forbes) which may be 
found a few inches beneath the surface of 
the ground, inclosed in a small, spherical 
earthen cocoon. They are about one-tenth 
of an inch broad by one-se renth of an inch 
long, and are white except the eyes and 
mandibles which show through the outer 
envelope red or black when the pupae are 
mature. The head, legs, antennae and 
wings are bent close to the 
body as is the case with all 
coleopterous larvae. In a 
short time they again appear 
upon the scene as mature bee- 
tles, so that although the in- 
sect is probably single brood- 
ed, it may defoliate the vines 
twice each season. First, 
early in spring," when the Fig. 266, 
leaves are just starting, and again in Au- 
gust and September just after transforming 
to the imago. 
Another insect which is very apt to be 
confounded with Paria aterrima, although 
readily distinguished from it by close obser 
vation, >s Scelodonta nebulosits, Sec. This 
beetle belongs to the same family and tribe 
of leaf-eating beetles as Paria aterrima, and 
hence the difference by which they are dis- 
tinguished in their immature forms, are 
not readily detected. The larvae of Scelo- 
donta nebulosus, correspond almost exactly 
with those of Paria aterrima except that the 
tips of the mandibles instead of being bisect 
as in the latter, are commonly entire and 
somewhat obtuse with the inner edge exca- 
vated. The difference 
between the pupae of 
the two species is even 
less marked. Prof. 
Forbes says: “The 
most careful compari- 
son of the pupae Of 
these tw T o species, has 
enabled me to detect 
only a single differ- 
ence between them. In 
Scelodonta the termi- 
nal abdominal hooks have each a strong 
erect tooth or spine attached to the up 
Fig. 263. 
per side of the base, while in Paria this 
spine is wanting. 
The mature beetles, (see Fig. 263, after 
Forbes) are more readily distinguished. 
While Paria aterrima is shining black, or 
brown with two black spots on each wing 
cover, Scelodonta nebulosus is purple or 
green, with a bronzed metallic lustre and 
is covered with a gray pubescence. They 
are also readily distinguished by the fact that 
the anterior margin of the thorax of Scelo- 
donta is straight beneath, instead of curv- 
ing forward beneath and behind the eyes to 
form the postocular lobes as in Paria, and 
from the fact that the hind tibiae are not 
toothed. Although the beetles so closely 
resemble each other, the periods of their life- 
history are curiously different and seem to 
be purposely so arranged that the insects in 
their various stages will not come in com- 
petition with each other in the struggle for 
existence. Paria feeds upon the leaves 
early in spring, deposits eggs in May or 
June, the larvae feed upon the roots in July 
and early August, during the fall months 
the beetles again infest the foliage, and then 
hibernate during the winter. Scelodonta, 
in the mature form, feeds upon the foliage 
in June, deposits eggs probably in July, and 
the larvae feed upon the roots from then 
until November when their active larvae life 
terminates. They pass the winter as nearly, 
or quite, full grown larvae in oval cocoons 
in the ground and remain in this stage un- 
til May when the change to the pupae oc- 
curs. We thus see that although both spe- 
cies may infest the plant at the same time, 
there is no active competition between them, 
for in June, when Scelodonta is feeding up- 
on the foliage, the larvae of Paria are feed- 
ing upon the roots, and from July to Nov- 
ember when Paria is feeding upon the foli- 
age the larvae of Scelodonta are feasting upon 
tender rcotlets. Again in early spring, 
while Scelodonta is wrapped in slumber, 
Paria improves the opportunity to obtain a 
“square meal” of strawberry leaves without 
being disturbed. 
Three methods of fighting these insects 
have been suggested. First, to repel the 
insects when in search of places to deposit 
their eggs. Second, to kill the larvae in the 
ground. Third, to destroy the beetles while 
feeding upon the leaves. Dr. Riley has 
suggested salt, lime, soot and ashes as re- 
pellants, and Prof. Forbes has been par- 
tially successful in destroying the larvae 
with bisulphide of carbon and with carbolic 
acid, but there is little evidence to show 
that these remedies are of practical import- 
ance. A better method of dealing with 
these pests, provided the field is to be 
plowed and replanted, is to plow soon after 
the fruit is picked. The larva? of Scelo- 
donta will be matured and many will com- 
plete their transformation, while Paria will 
at this time be found in the adult form 
feeding upon the leaves. Both will thus 
be deprived of their food supply 1 , and will 
inevitably be driven from the field, so that 
the new plants will be no more liable to 
attack than those in adjoining fields. The 
