INSECT PESTS OF OHIO SHADE AND FOREST TREES 257 



Life history and habits. — According to Doctor Garman (26), 

 adults have been secured in Kentucky in March and April as well 

 as in July and August, indicating two broods ; since the writer has 

 observed the larvae in large numbers in southern Ohio as late as 

 September and October, undoubtedly two broods occur in Ohio. 

 The winter is spent in the pupa stage. The caterpillars feed gre- 

 gariously, beginning at first with the under-surface of the leaves 

 but later consuming all portions excepting the petiole and midrib. 

 They do not feed upon the leaves which serve as their shelter; in 

 fact, as a special protection they secure these leaves to the twig by 

 silken bindings. 



Nature of work. — Doctor Garman (26) reports the species as 

 destructive to the foliage of street and lawn trees in Kentucky, but 

 under Ohio conditions the writer has never seen it in any role 

 excepting that of appearing occasionally on woodland and roadside 

 trees. Not only do the feeding larvae do bodily harm to the trees 

 when they appear in abundance, but the over- wintering tent rem- 

 nants detract considerably from the natural beauty of the host. 



Food plants. — Various species of poplar, particularly Populus 

 tremuloides, and various willows serve as hosts for this species. 



Distribution. — The poplar leaf-tyer has been reported from 

 various sections of the United States east of the Mississippi River 

 and as far west as Colorado. Of this area it is more abundant in 

 the eastern portion and in Ohio it is most frequently encountered 

 in the southern part. 



Natural enemies. — Doctor Garman (26) says: "The case 

 made by the larvae makes a very comfortable house, swinging in 

 the breezes, sheltering them from the weather, and, perhaps, to 

 some extent, from enemies; but as might be expected of a species, 

 individuals of which live closely crowded together, it is subject to 

 an epidemic disease that sometimes carries off most of the indi- 

 viduals of the second brood. It has some appearance of a bacterial 

 disease, the dead wonns quickly becoming limp and discolored, while 

 motile bacteria swarm in their body fluids in doubles of large size. 



They are attacked also by a gray fly parasite {Frontina fren- 

 chii) which emerged from confined lots in some numbers." 



Control. — Cutting out and destroying the leafy retreats with 

 their quotas of caterpillars is a simple and effective control measure 

 with small outbreaks. In the event of a widespread outbreak, how- 

 ever, spraying with poisons would be more satisfactory. 



