16 BULLETIN 1066, U. S. DEPARTMENT OF AGRICULTURE. 



flies, determined by Dr. J. M. Aldrich as Myiophasia globosa Towns., 

 CholomyuB longipes Fab., and Chaetochlorops inquilina Coq. (PL 

 VIII, D and E) , were reared from the larvae. Two larvae in rearing 

 cages died when full-grown and from each of their bodies there issued 

 a hairworm several inches long, the species of which was not deter- 

 mined (PI. VIII, C). 



METHODS OF CONTROLLING NUT-INFESTING CURCULIOS. 



The dropping of curculio-infested walnuts and hickory nuts before 

 the larvae within them mature affords an opportunity for destroying 

 the young insects by collecting and burning, or otherwise disposing 

 of the fallen nuts. This method can be resorted to with success, how- 

 ever, only in cases of isolated trees or plantations. In localities 

 where the nut trees abound in woods a sufficient number of the cur- 

 culio beetles will develop on them to visit and injure any near-by 

 'antations of the same kind. Where this means of reducing the in- 

 s its is practiced collections should be made as often as once a week in 

 order to secure the nuts before the larvae leave them to enter the 

 gr i id for the completion of their development. 



All the curculios discussed herein do more or less feeding in the 

 beetle stage before oviposition begins in the spring. A considerable 

 p- ft of this food consists of the surface tissues of stems, leaves, and 

 fra't. This makes it possible theoretically to destroy the beetles be- 

 foi their eggs are laid by spraying with arsenical poisons. Limited 

 experiments by the writer indicate that lead arsenate applications 

 soon after growth starts in the spring can be counted on to give good 

 results in reducing injury, at least from the butternut and black wal- 

 nut curculios. 



Britton and Kirk 13 have found that spraying walnut trees with 

 lead arsenate at a strength of 6 pounds to 50 gallons of water is an 

 effective method of controlling the butternut curculio. Morris, 14 in 

 writing of attacks of the butternut curculio which were so extensive 

 as to kill nearly 300 young English walnuts and several hundred 

 young Japanese walnuts, states that subsequent spraying with 1 

 pound of lead arsenate to 10 gallons of water killed the beetles and 

 prevented further injury. 



13 Britton, W. E., and Kirk, H. B. Op cit. 



14 Morris, Robert T. Method for combating the walnut weevil. In Amer. Nut 

 Journ., v. 10,. no. 5, p. 71. 1919. 



o 



