THE STRAW liF.KKV W KKNIL IN MINNESOTA 123 



Insecticides. 



Powdered lead arsenate and sweetened licinid lead arsenate 

 were tried out on a small scale as the weevils began to appear, but 

 with no apparent results. Spraying with a stomach poison appears 

 useless during- the egg-laying season, for at that time the weevils 

 feed principall}' on ])ollen, which, as was found in the case of the 

 cotton boll weevil, is absolutely necessary for the formation of 

 eggs. However, the old hibernating- weevils, as well as the new 

 brood upon emerging in the summer, feed (in the under side of 

 the leaves before the pollen is mature, liut the prtiblem remains, 

 how to get the poison on the under side of the leaves of such a low- 

 growing plant as the strawberry. 



Professor Headlee of New^ jersey reports the successful use of 

 a sulphur-arsenical dust experimentallv as a repellent. Two experi- 

 ments under practical conditions were, therefore, conducted in fields 

 where the weevils were abtuidant, by two difl:'erent farmers. Equal 

 parts of sulphur and powdered arsenate of lead were applied with a 

 powder gun on May 20, when about 8 per cent of the buds were 

 already cut. ( )n May 21 and 25 it rained, 'ilie material was again 

 applied on May 25 and May 30, and it rained again the next day. 

 Most of the material was washed off and since the material acts 

 as a repellent no apparent results were obtained. ( )n May 30, about 

 50 per cent of the buds w'ere cut in one of the fields, and the weevils 

 were present in the beds, wdiile on June 16. '^6 ])er cent of the buds 

 were cut. In the other field that was sprayed the weevils were not 

 so abundant, but they were present on the raspberry buds, which 

 they were cutting. They may have been driven o\ er by the spray. 

 In spraving an old bed, the weevils may also be driven to the new 

 beds. Because of the rainy s])ring weather and prolonged blossom- 

 ing season in Minnesota, and because only the older beds are severe- 

 Iv injured, spraying wdth a rei)ellent will not be entirely successful. 

 However, the sulphur-arsenical dust deserves further trial. 



Fencing. 



As the w^eevils do not fiy very far or very high, it seemed pos- 

 sible to keep them out of new beds by means of a fence. A wire 

 screen fence about two feet high was erected April 30, 1*)15. around 

 a plot of ground about ten feet square. This was banked up with 

 dirt around the bottom, and boards placed on top of the wire. 

 Tanglefoot was then smeared on both sides of the l)oards to deter- 

 mine if the weevil would attempt to fly or crawl in. Xo weevils 



