Aerie. -Forestry. Main Library. : . ; 



UNITED STATES DE 



Washington, D. C. 



August, 1922 



EXPERIMENTS WITH SPRAY SOLUTIONS FOR 

 PREVENTING INSECT INJURY TO GREEN LOGS. 



By F. C. CBAIGHEAD. 1 



in Forest Entomology, Forest Insect Investigations, Bureau of 

 Entomology. 



CONTENTS. 



Page. 



ses for repellent sprays against for- 

 est and shade-tree insects 1 



equisites of a practical spray 3 



It must be effective against sev- 

 eral types of insects 3 



It must be effective on various 



species of wood 4 



It must not be leached off by rain 



or other weather conditions 4 



It must not be expensive. _. 4 



(Requisites of a practical spray Con. 

 It must first prevent all insect in- 

 jury for from one to three 



months at least 



^Experiments with, preventive sprays__ 



Treatments and results 



Remarks on poisons used . 



Other experiments with insects of 



type3 



Poisoning of ambrosia beetles 



4 



4 



7 

 1O 



10 

 11 



rSES FOR REPELLENT SPRAYS AGAINST FOREST AND SHADE- 



TREE INSECTS. 



During the past few years there has been/an increasing demand for 

 practical spray that "will prevent insect attack to crude forest prod- 

 cts such as green sa/w logs and timbers used in rustic construction, 

 lumerous requests for such a spray are received by the Bureau of 

 Intomology. These inquiries often number more than a hundred 

 irough the summer months. 



Although many lumbering firms request a spray for this purpose, 

 ; is doubtful whether it would be really practical under ordinary 

 onditions. During the flight period of those insects which cause the 

 ijury it would be necessary to apply the spray immediately after 

 illing the trees. It is more practical to prevent insect injury in lum- 

 ering operations by some alteration in the methods of management, 

 3 by more prompt handling between felling and sawing or by sub- 

 icrging the logs in water, than by spraying. 



1 Resigned December 31, 1920. 

 10223022 1 



