218 
TREES AS GOOD CITIZENS 
particularly on twigs and the under side 
of leaves. There are several hundred 
varieties of the insects. Their principal 
damage is to the appearance of a tree and 
serious injury is not caused. 
POPLAR 
LEAF-CHEWING INSECTS 
Cottonwood, Poplar and Willow Leaf-beetle 
Habits These leaf-eaters are active 
and in every state of their develop- 
Damage. ment from birth to maturity 
and death, and the several 
succeeding generations of a single season 
may destroy all the leaves on a tree. 
They appear in the spring, after winter¬ 
ing on the tree, and at once begin feeding 
on the developing leaves, usually on the 
under side. In a short time the parent 
lays eggs on the under side of the leaves, 
producing a new generation. This pro¬ 
cess is repeated from three to five times 
each season. The presence of the insect 
is shown by leaves partly or entirely bit¬ 
ten through, early in the season, and later 
entirely consumed, by the beetles and 
grubs. As grubs the insects are short, 
stout, soft-bodied and spotted; upon 
developing into beetles they are hard- 
shelled, spotted or striped, and half an 
inch long. The eggs are yellow or reddish 
and are found in batches. Upon reaching 
maturity, the beetles issue from skins 
fastened to leaves, sometimes called 
“hangers.” 
Remedy. Spraying with lead arsenate 
is the most efficient measure 
of control for this insect. This spraying 
should be done as soon as the growth of 
the tree starts in the spring, when there 
are signs of the presence of the beetles. 
Care must be taken to direct the spray 
against the under side of the leaves. Soap 
added to the spraying material will be 
useful by causing the spray to stick to 
smooth leaves. 
Bagworm 
Spiny Elm Caterpillar 
Large Elm Sawfly 
Brown-Tail Moth 
Forest Tent Caterpillar 
White-marked Tussock Moth 
Fall Web worm 
(See descriptions and remedies under Elm) 
Cottonwood Dagger Moth 
Habits The leaf-chewing caterpillar 
and of this moth does serious dam- 
Damage. age to the Carolina Poplar and 
Willow in the prairie regions 
of the United States. A tree may be 
entirely stripped of leaves by the attacks 
of the two generations produced in a 
season. This caterpillar has a thick coat 
Remedy. Spraying is the most effectual 
remedy for this insect. Lead 
arsenate, thoroughly applied, will rid a 
tree of infestation. 
