TREE INSECTS AND THEIR CONTROL 
219 
of yellow hairs, long, soft and drooping, 
with five tufts of stiff black hairs on its 
back. The moths emerge from the chrys¬ 
alis in the spring and lay their eggs. 
From these are developed the caterpillars, 
which feed on the leaves and which when 
at rest, curl up on the under side of leaves. 
SAP-SUCKING INSECTS 
San Jose Scale 
(See description and remedies under Ash) 
BORING INSECTS 
Aspen Borer 
Habits This borer does considerable 
and damage to Poplars, and is 
Damage, especially prevalent in the 
middle and western states. 
The parent insect is a gray beetle, cylin¬ 
der shaped, having brown spots. This 
beetle’s eggs are laid in a scar in the bark, 
in May, June and July. On hatching, the 
grub begins its mining, and spends its 
first year tunneling just beneath the bark, 
following this with two years of mining 
deep into the wood. The boring grub is 
cylindrical, yellowish, and has a number 
of fine, short, hard points on a plate 
immediately behind its head. The sign 
of this borer’s presence is the appearance, 
in June or July, of irregular scars on the 
trunk of a tree, especially near crotches, 
from which there exudes sap carrying 
fibrous dust from the boring. Later there 
is an enlargement of the holes, with 
increased mass of discharge. 
Remedies. Spraying infested trunks 
in late summer with poisoned 
kerosene emulsion or miscible-oil solution 
is effectual in destroying the young grubs 
in the outer bark. Another helpful meas¬ 
ure is painting the eggs with creosote 
or carbolineum. When the young borers 
begin to tunnel into the wood in the fall, 
they may be dug out and killed; careful 
attention should be given to dressing the 
wounds caused by this treatment. Trees 
badly infested should be cut and burned. 
Bronze Birch Borer 
(See description and control under Birch) 
Mottled Willow and Poplar Borer 
Habits Of the enemies of Poplars 
and and Willows this is the most 
Damage, dangerous. The parent insect 
is a broad and stocky snout- 
beetle of dark brown coloring mottled 
with gray, and with pinkish tint at the 
rear of the wing covers. In length it is 
about inch. After emerging from the 
chrysalis stage in June or July the beetles 
feed on the young bark and after a fort¬ 
night the female deposits eggs in cavities 
Remedies. The surest way to destroy 
this enemy is by cutting and 
burning infested limbs or badly infested 
trees. This must be done in early sum¬ 
mer, before the insects emerge from the 
interior, in order to make sure that all of 
them are destroyed. This season is a time 
of great activity on the part of the grubs 
and the exuding sap and “sawdust” make 
it easy to detect their presence. A 
thorough coating of the bark with lead 
