particularly as we are unable to place the insecticide where they 

 would eat enough to kill them. 



Trap crops. — The cultivation of special varieties of nuts with a 

 view to securing imnuinity from attack or as a means of luring the 

 insects from the main crop does not offer any degree of promise. The 

 Paragon, Cooper, and Ridgeley varieties, according to ^iy. G. H. 

 Powell, of the Bureau of Plant Industry, suffer greater loss from 

 weevil attack than Japanese varieties. Chinquapins are favored by 

 the smaller weevil and suffer far more damage, as a rule, than wild 

 chestnuts. It is possible that the planting of the varieties specified, 

 or, better, of chinquapins, at intervals around, as also through, 

 orchards of the least affected varieties might lessen the loss to the 

 main crop. If a variety could be produced which would mature fruit 

 before the advent of the beetles in greatest numbers, this would 

 partially solve the j)roblem, particularly as the earliest nuts bring 

 the highest prices. The nuts gathered toward the end of the season 

 are comparatively uninjured, but by this time the market value is 

 considerably lower. 



Contact poisons, — Scarcely more can be expected from the use of 

 contact poisons, such as kerosene emulsion, since in view of the long 

 jDcriod spent by these weevils in the adult stage (from June and July 

 to September or October) such frequent application would be neces- 

 sary that the expense would destroy the profit. 



Jarring the trees, as practiced against the plum curculio, is for 

 the same and other reasons equally impracticable, save, perhaps, on 

 young trees grown in a small way. 



The water test of infestation. — Having doubts of the efficacy of 

 this old-fashioned test of the difference between " wormy " and 

 healthy nuts, an experiment was made by the writer Avith native 

 chestnuts obtained from a street vender. To begin, -40 per cent were 

 obviously '' wormy," and only 00 per cent apparently sound. 



Results of water tests with native chestnuts. 



As will be seen from this experiment, noticeably wormy nuts, as 

 evidenced by loss of Aveight and the exit holes of the '* worms,"' 

 naturally rise when placed in water, but the remaining nuts may or 

 may not be infested, and hence require further test than whether 

 they will sink or float. 



[Cir. 99] 



