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TREES AS GOOD CITIZENS 



selves by fastening leaves together with a 

 web of silk. These tents are at the ends 

 of twigs. Before going into winter quar- 

 ters in the tents, the young caterpillars 

 feed on the leaves, giving them a skele- 

 ton-like appearance, but without serious 

 damage. When the buds begin to form 

 in the spring the grubs start to devour the 

 bud scales and small leaves. This spring 

 feeding sometimes strips a tree of leaves 

 altogether. The growth of an infested 

 tree is badly checked. 



In appearance the adult moth is pure 

 white and the tip of the abdomen is cov- 

 ered with dark brown hairs. The moths 

 appear during the first week of June and 

 for several weeks they may be seen clus- 

 tered around electric arc lights. The 

 caterpillars are covered with poisonous 

 barbed hairs which cause severe irrita- 

 tion when brought into contact with the 

 human skin. 



San Jose Scale 



(See description and remedies under Ash) 



Bagworm 



Habits Less common than the Elm- 



and leaf beetle, but causes some 



Damage, damage. Appears in bags, 

 woven by the insect itself from 

 bits of foliage and a silk fibre. The eggs 

 are laid within the bags in September and 

 hatch into caterpillars the following 

 spring. The caterpillars begin at once 

 after hatching to feed on the leaves and 

 to construct bags for themselves. The 

 insect carries its bag with it in moving 

 from limb to limb or even from tree to 

 tree. In winter the bags are conspicuous 

 on the leafless branches. 



Concerted action on the part of an entire neighborhood is essential in the treat- 

 ment of the bagworm. 



Remedies. The bagworm has natural 

 enemies which usually serve 

 to keep it within bounds. The simplest 

 remedy is to pick the bags from the tree, 

 wherever this can be done, and burn them. 

 Where the bags can not be thus picked 

 by hand, or to destroy any which may 

 have been overlooked, the tree should be 

 sprayed with arsenate of lead soon after 

 the time of hatching in the early spring. 



Habits 



and 



Damage. 



A black, spiny caterpillar, 



marked with red, and about 2 



inches long; found in groups. 



Eats the leaves. Its presence 



is shown by partly eaten leaves or by 



entire branches or leaves becoming bare. 



Spiny Elm Caterpillar 

 Remedies. 



When the first signs of 

 injury appear the affected 

 parts of the tree should be thoroughly 

 sprayed with arsenate of lead. Where the 

 clusters are such as to make it possible 

 to remove them bodily without much 



