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hatched from such fields. On the otlicr hand, a close inspection of 

 neglected or abandoned fields revealed the fact that fields with the 

 stubble of 1888 contained large numbers of eggs, while the stubble 

 land of years previous to 1S88 contained either no eggs or very few. 

 No eggs could be found in the native prairie land, and but few in 

 pastures or ahmg roads and railroads. It was also shown that essen- 

 tially the same area as in 1888 was infested. 



In some fields as many as 75 per cent, or even more, of the eggs had 

 been destroyed by parasites, and in general throughout the whole in- 

 fested area it is safe to say that at least one-half of all the eggs had 

 been destroyed, principally by egg-feeding insects. An illustrated 

 description of the eggs of the locusts and the way in which they are 

 deposited in the fields is given. By plowing the infested field the eggs 

 are removed from the surface and covered with 5 or G inches of soil, 

 and the position of the burrow or hole containing the egg-mass is 

 inverted, so that its mouth points downward instead of upward. 

 Plowing has this additional advantage, that the egg-masses in most 

 cases are thus thoroughly broken up, individual eggs become sur- 

 rounded by earth and moisture, and being no longer protected by 

 their water-proof coat of dried mucous matter they soon perish. 



Methods em flayed to hill the locust. — (1) Plowing. — This was the 

 method most extensively employed in this case, and proved a great 

 success. Notwithstanding the fact that the natural conditions were 

 favorable to the locust, none hatched in plowed fields. As it was 

 found impracticable to plow all the infested fields in time to prevent 

 the eggs from hatching, the w^orst places Avere plowed first and after- 

 wards those that were less thoroughly infested, together with some 

 timothy fields and pastures. A large portion of this work was done 

 at the expense of the State. (2) Bnrning. — In many places where 

 the eggs were not numerous enough to warrant plowing the entire 

 field, a strip was plowed around the field and the inclosed space was 

 burned over after the young locusts appeared. (3) Catching with 

 hopper-dozers. — These were used with success in timothy fields and 

 pastures where the locusts had hatched. (4) Rolling. — This method 

 was tried in several instances by farmers without success. (5) Lon- 

 don purple. — This material was used as an insecticide for the locust 

 in several cases with marked success. 



An examination of soil from some of the plowed fields in July 

 showed that either the eggs were destroyed or, if they had hatched, 

 the young locusts had died before reaching the surface. 



The parasitic and predaceous insects mentioned in the annual 

 report of the Station for 1888 as feeding on the eggs of the locust 

 were equally abundant in 1889. Those mentioned in this bulletin are 

 the red mite {Tromhidium locustarinn) , bee fl}^ (Syntoschus oreas), 

 blister beetles, a click-beetle (Cryptohypmis bicolor, Esch., var. lacus- 

 18492— No. 4—05 M 5 



