Right: Lumber obviously reduced in value by 

 round-headed borers. 



Below: Holes and staining in this lumber indi- 

 cate the destructive work of ambrosia beetles. 



Photos by Robert L. Coffin. 



*~ijPS»si- 



tR^^^^ 



duction of the last one. One gallon 

 gave 87, 50, 90, and 78 percent re- 

 duction, respectively. Lower con- 

 centrations were less effective. 



Proper Handling Advised 



Because BHC, like all insecti- 

 cides, is poisonous, it must be 

 handled with whatever caution the 

 manufacturers advise. It also has 

 a musty odor, which some may fmd 

 objectionable. Properly handled, 

 it should be of value when winter- 

 cut logs cannot be converted into 

 lumber before spring. It might also 



be useful in cutting operations in 

 the summer. Some lumbermen 

 have already shown interest in 

 the possibilities of protecting 

 sawlogs by spraying. In all in- 

 stances, the insecticide must be 

 applied before the insects attack 

 the logs, but should not be ap- 

 plied when the logs are frozen. 



More Experimentation Needed 



Tests have been most promis- 

 ing, but more experimentation is 

 needed to determine the lowest 

 concentration of insecticide to 

 apply in different situations 

 against borers of these and other 

 kinds of logs. More information is 

 also needed regarding the possi- 

 bility of spraying piled logs effec- 

 tively, because if proved successful 

 in different situations it would lower 

 costs by reducing the amount of 

 insecticide needed and would save 

 extra handling of the logs. 



The above project was carried on by the 

 Entomology Department luith the coopera- 

 tion of the Forestry Department who provided 

 the logs and facilities and permitted the ex- 

 perimental work in its forest reservations. 



13 



