MONTANA INSECT PESTS 1945-1946 



15 



by. There may be as many as five generations per year, the last 

 group of adults going into hibernation. 



Asparagus beds which are not being cut for food can be spray- 

 ed with lead arsenate at the rate of 3 pounds to 50 gallons, or 1 

 ounce to 1 gallon, of water. Soap should be added in a quantit}^ 

 equal to that of the lead arsenate used. Dusting has been recom- 

 mended to replace spraying, using 1 part lead arsenate to 8 or 10 

 parts of lime. Asparagus being cut for food should not be treated 

 with an arsenical. Recommended treatment during this period 

 consists of dusting with a 5 per cent rotenone dust or spraying 

 with a rotenone extract. 



WHEAT STEM SAWFLY (Cephus cinctus) . — This insect re- 

 mains the primary wheat pest in Montana. A conservative estimate 

 of losses sustained in the State in 1945 is four million bushels. The 

 experiments on control of this pest have been carried out in co- 

 operation with the Department of Agronomy and Soils, and the Ex- 

 tension Service at Montana State College. The greatest hope for 

 immediate relief lies in the new wheat. Rescue, which is apparent- 

 ly sawfly resistant. It was developed at the Experiment Station 

 at Swift Current, Saskatchewan. From a start of two bushels, re- 

 ceived from the Canadian workers in 1944, there is an estimated 

 seed stock of 60,000 bushels in Montana at the present time. It will 

 probably be 1948 before any appreciable amount of this variety 

 reaches commercial channels. 



Figure 2. Approximate extent of Hessian fly infested area, 1945. 



