Xo. 6. DEPARTMENT OF AGRICULTURE. 389 



the spring brood of the fir develops at the lower joints of the wheat 

 and a great many "flax seeds" of this brood will be left in the field 

 at harvesting time. Turning the stubble under is also of value 

 where burning it would be difficult, provided the ground be then 

 rolled so that the flies which come from the -flax seeds"" will bo un- 

 able to reach the top of the ground. Some varieties of wheat are 

 more resistant to the attacks of the fly, than others. Among these 

 are the Clawson, Mediterranean. Red Cap, Underhill, Dawson"s 

 Golden Chaff and Prosperity. 



The destruction of volunteer wheat is important, as many flies pass 

 the summer in such ])lants. 



THE WHEAT STE:M MAGGOT OK WHEAT BULT5 WORM. 



(Meromyza americana Fitch.) 



The wheat-stem maggot has long been known as an enemy to 

 wheat in Pennsylvania, but its habits and injuries so nearly resemble 

 those of the Hessian Fly. that its woi-k is usually supposed to be 

 that of the latter insect by those nui familiar with it. 



Life Historv. 



This insect attacks wheat, barley, oats and various grasses. The 

 adult fly deposits its eggs on the wheat in September and October 

 and the maggots which soon hatch crawl down to some joint near 

 the bulb and feed upon the stalk, cutting it off. They pass the 

 winter in the stem, become quite pupji^ in April or May and the 

 adults emerge from these pupfP early in June. These adults usually 

 deposit eggs on the sheath of the upper leaf and the maggots which 

 hatch from them feed on the stem near the upper joint, causing it 

 to wither, and the heads to turn white. The adults produced from 

 these maggots appear in July and early August and their young at- 

 tack timothv. blue grass .volunteer wheat, etc.. and mature in time 

 to produce adults which deposit their eggs in September and Oc- 

 tober, as alreadv stated, on the voung winter wheat. There are, 

 therefore, three broods each year. 



Treatment. 



Little that is successful has yet been discovered in the way of treat- 

 ment for this insect. Late planting is useless as the insects may 

 lay their eggs as late as the middle of October. The summer brood 

 is probably the best place in the life of this insect at which to attack 



