U. S. D. A., B. E. Bui. .W, Part III. F. I. I.. March b. 1907. 



SOME INSECTS INJURTOrS TO FOliESTS. 



ADDITIONAL DATA ON THE LOCUST BORER. 



{Cylleiie robinisc Fon^t. )" 



By A. D. Hopkins, 

 /?i Cliarge of FnreM [iisni Live.^tif/ations. 



Tlii.s part of Bulletin 58 contain.s a partial revision of Part I, with 

 additional information based on the results of subsequent investiga- 

 tions by th«; writer and one of his assistants, ^Nlr. W. F. Fiske. 



SEASONAL HISTORY. 



The datii under this head refer to the District of Columbia and vicin- 

 ity, latitude 31>-, altitude 10 to 90 feet above tide. 



IIIHEHNATIOX. 



Hibernation ))e<;ins soon after the larva» hatcli from ecrg-s deposited 

 at various times from Augu.st to October, and the period is passed as 

 minute larvaB, scarcely longer than the eggs from which they hatch, in 

 snudl individual hibei'nating cells exca\ated by them just l)eneath the 

 corky bark and in the outer layers of the living bark on the main 

 trunk of the larger to small trees or small saplings, and larger to small 

 branches. 



AfTIVITV OK THK OV KKWINTKIM".!) I.AKN .K. 



Activity of the overwintered larva- begins in April, oi" with the l)egin- 

 ning of the movement of the sap in the bark and just before the leaf 

 buds open. In 1!>0(') activity began April 11: on April 1,'i th«> more 

 advanced individuals had entered to the wooii, <»m the Idth were groov- 

 ing the surface, and on the 2r)th some of them had entered the wood. 

 By May 11 nearly all of them had eiiter«Ml the sa])wood and some of 

 them had extended their burrows int«) the heartwood and were rapidly 



oOnier Coleoiitcni, Family Cerambycidfp. 



31 



