48 INJURIOUS INSECTS OF KANSAS. 



are dry during a large part of the year. On this belief (which 

 seems to be founded on sufficient evidence) he makes the follow- 

 ing recommendations for fighting the pests : 



1. To thoroughly break up the surface of the ground in and along 

 the ditches before winter by harrowing thoroughly, cultivating or shal- 

 low plowing, thus exposing the eggs to winter weather and natural 

 enemies. 



2. Wherever practicable, to flood the ground for a day or two at the 

 time young locusts are hatching. I was told that the young 'hoppers 

 were entirely unaffected by water, as they would crawl up the alfalfa 

 stems and escape, and it is probable that sufficient flooding to accom- 

 plish much good in this region is out of the question. My only hope 

 in this line would be in watching carefully for the time of hatching, and 

 using the water before the 'hoppers had obtained any growth; and, if 

 abundant along the ditches, putting a little kerosene on the water. 



3. A use of the * hopper-dozer as early in the season as possible, when 

 I believe the treatment of a strip 8 or 10 feet wide on each side of the 

 ditches would destroy so large a part of their numbers as to prevent 

 any serious damage. As I learned from a number of parties the 'hop- 

 pers are scarcely half-grown when the crop is cut, it would seem that 

 immediately after cutting the first crop would be the best time to use 

 the hopper-dozer. The 'hoppers would be large enough to jump readily, 

 and the dozers could be run very easily. It would be difficult to use 

 them at any other time than directly after the crop was cut, as the dense 

 growth of alfalfa would obstruct their movement. 



My strongest recommendation would be the urging of effort in break- 

 ing up egg masses before winter, and then, in case locusts still appear 

 in any number in spring, to resort to the dozers at first opportunity. I 

 believe active use of these measures will be effectual, with a cost but 

 trifling compared with the value of tha crop to be saved. 



Skunks, toads and certain Tachinid flies do much toward keep- 

 ing these pests in check. Professor Osborn states that he noted 

 several dead grasshoppers which " had the appearance of having 

 been affected with Entomophthora." 



I attempted last summer (1891) to inoculate specimens of dif- 

 ferentialis and bivittatus from Garden City with Empusa ( Ento- 

 mophthora ?} aphidis, (a parasitic fungus growing freely on 

 Chinch-bugs in our laboratories,) by enclosing the grasshoppers 



* A "hopper-dozer" is a machine for catching grasshoppers, usually in the nature 

 of a broad tray containing coal-tar or kerosene, to be pushed or pulled over the in- 

 fested field. The grasshoppers fly or hop into the tray, or are sucked in by means of 

 fans, and meet a sticky or oily death in the tray. (For descriptions and directions for 

 construction of " hopper-dozers" or locust-catchers, see "Destructive Locusts: " Riley, 

 Bulletin 23 (1891), Division of Entomology, U. S. Department of Agriculture.) 



