INSECTS AFFECTING OHIO SHADE TREES 185 



The Forest Tent Caterpillar, P"?* the last *?* Centt "T K the , re 

 Malacosoma disstria Hubn. have been occasional severe outbreaks 



of this insect in widely separated sec- 

 tions of the United States, the hard maple being: the principal suf- 

 ferer in the north. 



The eggs are deposited in late summer, usually upon the lower 

 branches of the tree, though they sometimes may be found upon 

 the topmost twig's. They are placed in belts of about 150 each sur- 

 rounding- small twig's. After the egg- is deposited, the larva de- 

 velops within the eg-g-shell, but does not break through until the 

 following spring, about the time the leaves are appearing. As the 

 larvae feed and develop, they do not spin a sheltering web as do some 

 of the other leaf-feeding caterpillars, but, as they pass up and down 

 the limbs of the tree, they spin a silken thread behind them, which 

 after many passages becomes a silken path. . When not feeding up- 

 on the leaves they rest in clusters upon the limbs and trunk of the 

 tree. They also take this position to shed their skins. 



The full grown caterpillar is about two inches in length and is 

 characteristically marked with a blue head and a row of diamond 

 shaped spots down the middle of the back. 



The cocoons are spun in any sheltered position, such as among 

 crumpled leaves on or under the tree, in crevices of the bark and of 

 fence-posts, etc. They are composed of the hairs from the insect's 

 body, silken threads, and a liquid which the caterpillar ejects, the 

 latter giving the mass a yellow, powdery appearance. 



The adult is a brown moth, bearing a darker colored band 

 across each fore-wing, almost parallel to the outer border. They 

 fly mostly at night. 



Concerning remedial measures, as with the tussock moth, much 

 good may be accomplished by collecting and destroying the egg- 

 masses during the winter months. However, this method is not as 

 fully applicable in the present instance as the egg-masses are not 

 so conspicuous. Probably the best method of control is spraying 

 with arsenicals at the time the larvae appear. As with the tussock 

 moth it will probably be of advantage to band to prevent reinfes- 

 tation. 



The distinguishing characteristic of 

 The Fall Web Worm, ,, . , . . , 



Hyphantria textor Harris. thls msect 1S seen m the lar ^ e un ~ 



sightly webs occurring most commonly 



upon wild cherry during the late summer. Upon critical examina- 

 tion, it is seen that the webs contain a quantity of hairy larvae 

 which feed upon the more or less browned leaves of the twigs en- 

 closed. This discoloration results from the insect's eating the 



