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 

 These leaf-eaters are active Remedy. Spraying with lead arsenate 



Habits 



and 



Damage. 



in every state of their develop 

 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." 



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 



(See 



Brown-Tail Moth 

 Forest Tent Caterpillar 

 White-marked Tussock Moth 

 Fall Webworm 



descriptions and remedies under Elm) 



Habits 



and 



Damage. 



Cottonwood Dagger Moth 



The leaf-chewing caterpillar Remedy. Spraying is the most effectual 



of this moth does serious dam 

 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 for this insect. Lead 

 arsenate, thoroughly applied, will rid a 

 tree of infestation. 



