130 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



reddish or yellow. The larvae are grayish above and lighter 

 beneath and reach a length of about a half-indi. They appear 

 like any common small caterpillar but on examination will be 

 found to have eleven pairs of legs in place of the eight pairs found 

 on the caterpillars. 



A third species, more common than any of the others is the 

 Grass Saw-fly, (Pachynematus extensicornis Norton). The adults 

 of this species do not differ markedly from the others but the larvae 

 became larger and are green or yellowish-green in color and have 

 only ten pairs of legs in place of the eleven pairs found in the 

 former species. 



Adults of all these forms appear rather early in the spring and 

 larvae feed on the wheat, then in mid-summer go into the ground 

 and remain there as larvse until early the next spring. They 

 may possibly be destroyed in this situation by deep plowing, 

 which would prevent the escape of the adults. So far, injury 

 has not been extensive enough to call for treatment. 



Some Wheat-maggots 



Very similar to the Hessian fly in its mode of injuring the 

 wheat-stalk is the Wheat-stem Maggot (Meromyza americana 

 Fitch). The adult flies were first described by Dr. Fitch in 1856, 

 though the work of the maggots had probably been noticed as 

 early as 1821 by James Worth of Bucks County, Pa., and by the 

 Michigan Farmer in Michigan about 1845. 



Extending from Dakota and Manitoba to Texas, the range 

 of this insect practically covers all the eastern United States and 

 southern Canada. 



Unlike the Hessian fly it feeds and breeds upon wild grasses and 

 is thus much more difficult to control. Prof. A. J. Cook found 

 the larvse in both barley and oats in Michigan, Prof. F. M. Webster 

 reared an adult from blue grass (Poa pratensis), and Dr. Jas. 

 Fletcher records it as breeding in Agropyrum, Deschampsis,Elymus, 

 Poa, and Setaria viridis in Canada. 



Life History. Like the Hessian fly the adult flies lay their 

 eggs on fall wheat in September and October, and the young 

 maggots when hatched work their way down into the stem, either 

 cutting it off or causing it to discolor or die. The eggs are about 

 one-fortieth of an inch long and of a glistening white color. The 



