208 



esters of cholesterol. Bioassays with natural and synthetic cholesteryl 

 esters were used to confirm activity. The activity of the cholesteryl esters 

 was also confirmed by using females that had not been previously exposed to 

 hosts. 



403. Himel, C. M. 1969. The physics and biology of the control of cotton 

 insect populations with insecticide sprays. J. Ga. Entomol. Soc. 4: 

 33-40. 



The fluorescent particle spray droplet tracer method (FP method) is a new 

 and valuable research tool which gives data on the physics and biology of 

 Insecticide spray droplet transport and impingement. The importance of the 

 FP method lies in the fact that it can be used in the field in the act'ial 

 environment of the target insect to determinethe actual number and si7.e of 

 spray droplets reaching the target (or non-target) insects and foliage. Over 

 100,000 droplets of spray material applied to a cotton field were identified 

 by size and number on a total of 978 boll weevils, bollworms and cabbage 

 loopers. In addition, cotton foliage and dissected cotton squares were 

 examined in detail. Of the droplets found on the target insects, 99.4% 

 were 40 \\ or smaller and, of nearly 600 spray droplets that penetrated the 

 squares, 95% were in the range of 20 y. The mathematics and physics of 

 the relation of spray droplet size to efficiency of application is discussed. 



404. , and Moore, A. D. 1969. Spray droplet size in the control of spruce 

 budworm, boll weevil, bollworra, and cabbage looper. J. Econ. Entomol. 

 62: 916-918. 



The fluorescent particle spray droplet tracer method was used under field 

 conditions to determine the size and number of spray droplets which impinged 

 on spruce budworm, Choristoneura fumlferana (Clemens) , in a Montana mountain 

 forest and on the boll weevil, Anthonomus grand is Boheman; bollworm, Heliothis 



