Feb. is, 1921 Leconte's Saw fly, an Enemy of Young Pines 



759 



and since this insect shows a very decided preference for young trees, 

 and the larvae often are numerous enough to strip the tree entirely of 

 leaves, many young pines are killed by this work alone. Trees not com- 

 pletely denuded often die because in their weakened condition they are 

 attacked by secondary insect enemies. When there is incomplete 

 defoliation and the tree recovers it is often stunted or misshapen and 

 is of little commercial or ornamental value. 



FlG. 3. — Distribution of Neodiprion leconlei. The larger dots indicate places from which specimens have 

 actually been received. See also footnote 2, p. 758. 



MEANS OF CONTROL 



The control of this species depends largely on the extent and location of 

 the infestation. In large areas of either natural or artificial reproduction, 

 control because of its expense can not be generally practiced, but rangers 

 and lumbermen should make it a practice to destroy the colonies of these 

 larvae whenever they are found. The easiest way is to knock the larvae 

 from the trees and crush them with the foot. 



In nurseries and in parks the control, in case of heavy infestation, can 

 best be attained before the larvae are full-grown and should consist of 

 thorough spraying. An arsenate of lead spray of 2 pounds of powder 

 to 50 gallons of water (or a ratio of 1 to 12) should be satisfactory. On 

 larvae which are discovered when young, less than >^-inch long, nicotine 



