386 NEW YORK STATE iMTSEUM 



Spruce bark beetle 



Polvgi-iTp/uis riifipciniis Kirh)- 



A liuht brown or lilark, ratlu-r stout licetlc aljoiit '• \. im li in length makes somewhat 

 irregular transverse galleries, trom which diverge smaller dilating lar\al galleries, in the 

 inner hark of sprnre. 



This \'ery common species in the Adirondacks is a dangerous enemy 

 of the sj^-nce. It can usually Ite toiind in small numhers in this tree and it 

 is fi"e(|iiently present in great abundance in the bark of cut logs or 

 trimmings. This Ijark borer was taken by the writer in 1900 in several 

 localities in the Acliroiidacks. It was found Aug. 14, 1900, in all stages in 

 the bark of cut spruce logs and some nearb)' fallen spruce were badly 

 infested Ijy the insect. It was present Aug. 22 at A.\ton, breeding in large 

 numbers in logs cut sometime during the preceding month. Old beetles 

 were scarce at this time and there were numerous larvae and few pupae, 

 indicating that the infestation was a comparatively recent one. This insect 

 was also founil at work in considerable numbers in spruce tops cut between 

 September and December of the i)receding year, and remains of tliis species 

 were found under the bark of deatl spruces standing on the edge of Little 

 Clear pond at .Saranac Inn. Large numbers of trees had been affected in 

 in this manner aiul the primar)' cause of the trouble in this particular 

 instance was proijaldy the raising of the level of the pond, which had 

 occurred several years earlier. This borer was found by the writer 

 associatetl with species of Dryocoetes in spruce and with Tomicus 

 balsameus Lee. in balsam, and Dr Hopkins records finding a single 

 e.xample in |)inc. 



Early history. Very little has apjjarently been recorded concerning 

 this borer aside from the facts matle known by Dr A. D. Hopkins who has 

 made an exhaustive stud\- of this insect in West \'irginia, and writing of it 

 in 1893, states that it infests black spruce. His studies led him to believe 

 that it was a vi-ry dangerous enemy of this tree and that it may have been 

 the s[)ecic-s to blame for the great destrticti(jn of spruce timl)er in W^est 

 Virginia in 1883 to 1885. 



