50 THE SUGAK-BEET WIREWORM. 



of great economic importance, for when sound eggs were isolated in 

 the cage in which the fungus was working they were seldom attacked, 

 shomng that the fungus must spread slowly. Its appearance was 

 jjrobahly the result of unfavorable artificial conditions. 



REMEDIAL MEASURES. 



Historical. 



Most of the literature thus far devoted to the study of wireworms 

 from an economic standpoint has been a consideration of remedies. 

 Probably no other insects have had more remedies tried for their 

 control and with less success. Some of the remedies have been par- 

 tially successful, but generally their cost has been such that their use 

 for average crops is entirely impractical. One which would come 

 under this head was a method tried on a small scale in Europe some 

 time ago and consists in baiting the wireworms and collecting them. 



Eleanor A. Ormerod,^ studying several species, gave as remedies (1) 

 compacting the ground, (2) clearing off vegetation, and (3) making 

 appUcations of gas lime. She staled that crop rotation was of little 

 value. John Curtis ^ suggested as remedies frequent plowing to turn 

 up the larvae, and appUcations of soot and lime. Mary Treat,^ writ- 

 ing on these insects, suggested spring and fall plowing and the trap- 

 ping of larvae. Fall plowing as a remedy was recommended by C. M. 

 Weed.* 



The two most important sets of recommendations based on actual 

 exhaustive experiments and careful study were those of Comstock and 

 SHngerland ^ at Cornell and S. A. Forbes ^ in Illinois. Their recom- 

 mendations are quite different, Forbes suggesting a careful rotation 

 of crops, while Comstock and Slingerland advise fall plowing for the 

 destruction of the pup^B and trapping the adults with poisoned bait. 



Tests of Suggested Remedies x4lGAinst the Sugar-Beet Wire- 

 worm. 



In testing remedies for tlie sugar-beet wireworm only those were 

 tried which heretofore liad promised at least partial success and which 

 were at the same time thoroughly practical. 



attempts to destroy the adults with poisoned baits. 



Experiments with poisoned bait were carried on against the adults, 

 using the bait much after the method suggested by Comstock and 



1 Manual of Injurious Insects and Methods of Prevention. By E. A. Ormerod, 1890, pp. 109. 



2 Farm Insects. By John Curtis, 1860. 



3 Injurious Insects of Farm and Garden. By Mary Treat, 1882. 

 < Insects and Insecticides. By C. M. Weed, 1891. 



i Bull. 33, Cornell Agr. Exp. Sta., 1891. 

 « 18th Rept. State Ent. 111., 1891. 



