22 



NEW YORK STATE MUSEUM 



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Fig. 31 Elm bark lice on twig, 

 full grown females (original) 



other parts of the state. The draft on a badly infested tree in 

 June is very great; the excretions of the bark lice falling in fine 



showers keep stones beneath wet even on 

 good drying days. The leaves of infested 

 trees are frequently covered with a black- 

 ening fungus, which grows in this secre- 

 tion. 



Treatment: spray the young with kero- 

 sene emulsion or whale oil soap solution. 

 39 Elm borer (Saperda triden- 

 t a t a). Diseased or dead bark is usually 

 the first indication of injury by this in- 

 sect. The tree soon becomes unthrifty 

 and examination of the bark may show 

 in its inner portions white, flattened, legless grubs, which fre- 

 quently cause consider- 

 able injury. The beetles 

 appear from early May 

 till latter part of June. 



Treatment : cut and 

 burn badly infested trees. 

 Protect valuable trees 

 with carbolic soap wash 

 during May and June. 

 40 Elm snout beetle (Magdalis barbita). Thick, fleshy, 

 legless grubs working in inner bark of elm. 

 Follows attack by the elm-borer and occa- 

 sionally is very abundant. The parent 

 insect is a black snout beetle about ^ 

 inch long. It sometimes occurs in large num- 

 bers and may have associated with it the 



beetTe/^ MagdTus Tcddish, closcly allied Magdalis ar mi- 

 bar bit a (original) , , . 



C O 1 1 1 S. 



Treatment: burn badly infested trees and keep others vigorous. 



Fig. 32 Elm borer : a adult; h half grown larva— hair 

 line represents natural size of latter (original) 



