INSECTS INJURIOUS TO THK GR.VIXS AND GRASSES. 71 



or seriously injured, and only saved by a most persistent 

 fight against the locusts. 



The eggs are deposited in a single mass of from 103 to 

 132, mostly from August 10 to September 15. The young 

 hatch from the eggs during the first three weeks of May 

 and, after molting five times, become full-grown by the 

 last week in June. They mate about the middle of July, 

 and the eggs are laid a few weeks later. 



Our largest American locust, the American Acridium 

 (Schisfocerca ainericaiia Scud.), is practically confined to 

 the Southern States from the District of Columbia to 

 Texas, and thence south through Mexico and Central 

 America, being rarely found in the Xorth. This species 

 is essentially a tropical one, and has often been exceedingly 

 destructive, being especially so in 1876 in Missouri, 

 Tennessee, North Carolina, Georgia, and southern Ohio. 



Remedies and Preventives. — All of our destructive 

 locusts having essentially the same life-history and habits 

 except that of migrating, methods of combating them will 

 apply almost equally well to all, but must, of course, be 

 judiciously determined according to existing local condi- 

 tions. 



Destruction of the Eggs. — Of first importance in this 

 warfare is the destruction of the eggs. In Europe, where 

 labor is cheap, this is often done by hand-picking. That 

 would hardly do in a western corn-field or wheat-ranch, 

 They may, however, be quite successfully destroyed either 

 by fall plowing or harrowing. In harrowing, ''the object 

 should be not to stir deeply, but to pulverize the soil as 

 much as possible to about the depth of one inch. Where 

 the cultivator is used, it would be well to pass over the 

 ground again with a drag- or brush-harrow for this pur- 



