4-H CLUB INSECT MANUAL 



63 



The information gained from surveys with reference to the cotton 

 boll weevil would be important. The early spring survey to be made 

 about the time cotton is chopped would indicate the number of wee- 

 vils emerging from hibernation. When 40 or more weevils per acre 

 are present on any given field, control measures are likely to be 

 necessary on that field, and arrangements for applying such measures 

 should be made. 



The square-infestation survey should be made on each field when 

 the cotton begins to fruit,, to determine when 10 percent of the squares 

 are infested. If cloudy, rainy weather, which is favorable to boll 

 weevil development, prevails, dusting with calcium arsenate should 

 be started. 



The occurrence of scale insects increases and decreases from year 

 to year. Too often damaging infestations are not located until the 

 trees or shrubs are in foliage. Control measures for scale insects 

 are applied while trees are in the dormant period. If the public 

 could be taught to be on the lookout for these pests and to consult 

 entomologists, control measures could be started during the dormant 

 period before damage to the trees occurs. 



Possibly one of the best examples of the effectiveness of surveys 

 is that made for the hessian fly. Through a survey made each sum- 

 mer by entomologists, the danger of hessian fly infestation in wheat 

 sown in the fall is determined, and if necessary the farmers are 

 warned to observe the safe seeding dates. Club members in terri- 

 tory where the hessian fly is prevalent could, by familiarizing them- 

 selves with the survey, do much to assist entomologists, as well as 

 to educate farmers, regarding the value of withholding planting until 

 after the safe seeding date. 



