18 MISC. PUBLICATION 7 4, TJ. S. DEPT. OF AGRICULTURE 



trees in the plantations of the Nebraska National Forest at Halsey s 

 Nebr., and in Minnesota. 



DEFOLIATING INSECTS 



THE LOCUST LEAF MINES 



Chalepus dorsalis Thunb. 



The locust leaf miner causes widespread defoliation of black locust. 

 It is abundant practically every year over considerable areas of its 

 range from Massachusetts through the southern Appalachians and 

 the Ohio Valley. The feeding causes the leaves of the trees to turn 

 brown in the late summer. No study has been made of its eil'ect 

 on the growth of the trees (48, 53) . 



THE GRAPE COLASPIS 



Colaspis brunnea Fab. 



Widespread defoliation of pines in the Gulf States in 1925 and 

 1926 was attributed to this small beetle. The species is not often 

 so abundant. Severest injury occurred in southern Louisiana and 

 eastern Texas. Young trees were more severely infested than older 

 ones. 



THE OBANGE-.STRIPED OAK WORM 



Anisota senatoria A. and S. 



THE SPINY OAK WORM 



Anisota stigma Hbn. 



THE GREEN-STRIPED MAPLE WORM 



Anisota rubicunda Fab. 



Throughout the eastern hardwood belt oaks are frequently de- 

 foliated by the orange-striped oak worm, the spiny oak worm, and 

 Anisota virginiensis Drury, and maples by the green-striped maple 

 worm. The first-mentioned species is the most important and in- 

 jurious (25, U, 48)- 



THE BIRCH LEAF SKELETONIZES 



Bucculatrix canadensisella Chambers 



This insect is a frequent defoliator of birch throughout the north- 

 ern part of the United States and Canada and feeds to some extent 

 on alder and oak. 



THE SPRUCE BUD WORM 



Cacoecia fumiferana Clem. 



The spruce bud worm is periodically one of the most destructive /*" 

 forest insects in the United States. A recent epidemic in the North- Wi 

 eastern States and Canada destroyed from 50 to 75 per cent of the 

 spruce and fir over great areas. In the Lake States and locally 

 throughout the Rocky Mountains notable losses have been reported. 

 The caterpillars feed on fir, spruce, Douglas fir, pine, larch, and 

 hemlock {64). 



