CONTROL OF MORMON CRICKET WITH POISONED BAIT 13 



Such conditions existed in South Dakota at the time the large-scale 

 tests were made and undoubtedly accounted for the higher percentage 

 of kill obtained with mill-run bran and sawdust as the carrier. 



As a result of the large-scale tests in South Dakota, the cricket- 

 control program in two counties in that State, Mellette and Jones, 

 was switched over almost entirely to baiting with 1 part of mill-run 

 bran to 3 parts of sawdust and 4 pounds of sodium fluosilicate per 

 100 pounds of carrier. The final results of this campaign are not 

 available, but good kills were reported by farmers and control officials 

 throughout the season. 



Other large-scale tests were made in Wyoming through a cooperative 

 project between the Office of the Wyoming State Entomologist and 

 the Bureau of Entomology and Plant Quarantine. The final results 

 of this program, as given in a report by Robert Pfadt, 4 show that an 

 area containing 10,240 acres, east of Sheridan, Wyo., was entirely 

 cleared of crickets through the use of bait alone. In all, 22,250 pounds 

 (dry weight) of bait was used on 1,584 acres, or an average of 14 pounds 

 per acre. The total cost of the project, including the cost of materials, 

 labor for mixing and spreading, and transportation of bait spreaders, 

 was $881.21, or an average of 56 cents per acre treated. This cost 

 was unusually high because of the demonstrational character of the 

 project. Based on the experience gained from large-scale grass- 

 hopper baiting projects, this cost should not exceed 30 cents per acre 

 with use of the standard bran formula, or 25 cents per acre with the 

 mill-run-bran-and-sawdust bait. 



Samples from the fields were collected by the wing-pen method and 

 the numbers dying in 96 hours or less after baiting ranged from 73.3 

 to 100 percent, with an average of 91.9 percent over the period of 34 

 days of baiting. Practically all the bait used in Sheridan County was 

 spread during the forenoon. 



Additional data on seven tests in Crook County, Wyo., in which 

 the bait was spread during the afternoon, showed mortalities, of 36 

 to 89 percent, and an average mortality of 69 percent, in 96 hours. 

 Practically all the bait had 1 part of mill-run bran and 3 parts of saw- 

 dust as the carrier. Four pounds of sodium fluosilicate to each 100 

 pounds of carrier was used in all tests. 



RECOMMENDATIONS FOR BAITING CAMPAIGNS 



As a result of the 4 years' experimental work summarized in this 

 circular, highly effective and practical baits for the control of the 

 Mormon cricket have been developed, the best time for applying 

 them and the rate at which they should be spread have been deter- 

 mined, and recommendations can now be made for large-scale field- 

 control projects. 



Recommended Bait Formulas 



In areas where cricket control is the main objective the following 

 formula is most likely to give best results under all conditions: 



Standard bran 100 pounds 



Sodium fluosilicate 3 pounds 



Water 10 to 15 gallons 



* Report to the Division of Domestic Plant Quarantines, Bureau of Entomology and Plant Quarantine, 

 TJ. S. Department of Agriculture. 



