74 



OTHER BORERS AFFECTING CONIFERS. 



Owing to the absence of Dendrocionus frontalis at the time its investi- 

 gation was attempted, little time was devoted to the boring species 

 affecting coniferous trees. The following, however, are worthy of 

 mention : 



Leptostylus commixtus Hald. — Under this name a cerambycid has 

 been included in Fitch's list of pine insects of New York State, on the 

 strength of the occurrence of the beetle on pine leaves. What the 

 writer takes to be the same species was reared at this Department from 

 pieces of Pinus inops taken at Wedderburn, Ya. 



Graphisurus pusillus Kby. — Taken by Mr. Ashmead under bark of 

 Pinus inops in an oval, cell-like depression prepared by the larva before 

 pupating. WedderburD, June, 1893. A rare species. 



Acanthocinus nodosus Fab. — This large, showy species has been 

 recorded to occur " under the bark of pine from June to September," 

 in the neighborhood of Philadelphia (Proc. Ent. Soc. Phila., Vol. I, p. 

 97), and is ordinarily of rare occurrence. It was fairly abundant in 

 the streets of Washington during the summers of 1894 and 1895. At 

 one time a half dozen individuals were noticed under a single electric 

 light, where they were being trodden upon by pedestrians. Without 

 doubt this unusual abundance was due to the many dead trees killed 

 by Dendroctonus frontalis in the vicinity. 



PROBABILITY OF FUTURE DESTRUCTION OF FOREST AND SHADE TREES. 



The severe windstorms that have swept over the South Atlantic 

 States during the past year, particularly that of September 29, which 

 was the severest ever known in this region and caused very extensive 

 destruction of forest and shade trees, will doubtless result in still 

 greater destruction to trees through the opportunities that the dead, 

 dying, or injured trees afford for the propagation of injurious insects. 

 It should be borne in mind that wood- and bark-boring insects generally 

 prefer timber that has been recently killed, and that when this is not 

 available they will attack injured, weakened, or even healthy growth. 



PREVENTIVE AND REMEDIAL MEASURES CONSIDERED. 



Such owners of forest land as have sufficient financial interests at 

 stake will do well to clear up the dead, and trim the injured, trees. For 

 the protection of chestnuts ail dead oaks should also be cleared away 

 and burned, and the same is true in the case of pines and other coni- 

 fers. Much can be accomplished by simply removing the bark of the 

 dead timber. The injurious species require as a rule a year for develop- 

 ment. The first warm days of April and May will see the first numbers 

 of the invading host upon the dead and injured trees. The succeeding 

 month these will give place to other species, and by the end of July the 

 most of these will have laid their eggs in cracks and crevices in and 

 under the bark and have disappeared. 



