April, '19] RICKER:. GRASSHOPPER BAITS 197 



slightly heavier infestation gave an average of 50 dead hoppers to the 

 square yard or approximately 75 per cent. Lemon fruit and salt gave 

 practically the same results as molasses and salt with average square 

 yards showing from 35 to 40 dead hoppers or about 70 per cent. In 

 this series salt alone resulted in an average of 30 dead hoppers to the 

 square yard or about 65 per cent, while molasses alone gave 28 dead 

 hoppers to the square yard, or about 60 per cent. 



These experiments further show that apples and molasses gave 

 practically the same results as lemon fruit and molasses; that lemon 

 fruit and salt gave practically the same results as molasses and salt, 

 but that both were slightly less effective than the first two combina- 

 tions. Salt alone seems to have given slightly better results than 

 molasses alone. 



Another series on September 3 resulted in banana alone obtaining a 

 kill of 35 to 40 hoppers to the square yard or approximately 85 per 

 cent, while apple alone resulted in from 25 to 30 dead to the square 

 yard, or about 75 per cent. Molasses alone, at the usual rate, gave 

 48 dead to the square yard, or approximately 90 per cent, while mo- 

 lasses alone, at double strength, but sown in standing corn, gave a kill 

 of 15 to 20 hoppers to the square yard, or 85 per cent of the infestation. 



Grasshopper injury to tobacco shows up as holes in the tobacco 

 leaves. This makes the tobacco useless as binder tobacco and results 

 in a very low price for the crop. Since a small infestation can in a 

 very short time eat holes in a considerable amount of tobacco, the use 

 of something which will give a quick and maximum kill means a con- 

 siderable saving. In several experiments bananas were substituted 

 for the lemon fruit in the standard bait, applications being made under 

 similar conditions and in all cases the banana gave as good results as 

 the lemon fruit and seemed to give a heavier early mortality. This 

 indicates that banana might be of special value when treating tobacco 

 which, this year in southern Wisconsin was estimated as being worth 

 $450 an acre. 



Period of Attractiveness of Different Fruits 



One marked difference between the citrous and non-citrous fruits, 

 such as apples and bananas, is that citrous fruits become flat within 

 a day or two after application, whereas the non-citrous fruits men- 

 tioned above increase in odor and attractivensss as fermentation 

 progresses. This factor should make baits attractive for more than 

 the one or two days during which the citrous baits are effective. CJrass- 

 hoppers and crickets have been observed feeding upon the non-citrous 

 baits as late as the eU^-enth and twelfth days after application, although 

 no hoppers coukl l)e found at that time feeding upon the citrous baits 



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