GENERAL CROP PESTS 69 



are burned. Whatever remedy is employed should be applied 

 at the outset of attack in order to be of substantial value. 



GRASSHOPPERS AND RELATED INSECTS 



Of great importance in the West, and in some seasons in other 

 regions, are numerous species of locusts, or short-horned grass- 

 hoppers. Several related insects, such as katydids and crickets, 

 are also injurious. All of these are general feeders, and as a 

 rule destructive to vegetable crops only in seasons which have 

 been particularly favorable to their multiplication. The num- 

 bers of species of these insects mount into the hundreds, but 

 the most important forms might be reduced to a double score. 



For present purposes it will be necessary to mention only a 

 few of the most abundant forms. Grasshoppers are mostly 

 large insects, with mouth-parts formed for biting, with young 

 more or less closely resembling the adults, save for the lack of 

 wings. Their name is sufficient indication of their habits : they 

 live normally in grasses, and their hind thighs are enlarged 

 for leaping. Everyone knows them so well that further descrip- 

 tion is unnecessary. . Some species are capable of extended 

 flight for hundreds of miles with intermissions of daily stops 

 for food. At such times they occur in swarms, and sometimes 

 darken the face of the sun, or at night of the moon. 



Grasshoppers may be classified in regard to their habits as 

 non-migratory and migratory. In the latter group are our com- 

 monest species which breed and pass their entire lives in or 

 near the place where the eggs were laid from which they de- 

 velop. The migratory species develop in enormous numbers, 

 and when they become too abundant for the food supply of the 

 region where they originated .they migrate. They are most 

 troublesome in arid and semi-desert regions, and their numbers 

 are subject to variation according to climatic conditions and 

 locality. Dry regions are liable to the visitation of a locust 



