230 



INSECTS AFFECTING WHEAT. 



fall wheat. Consequently there are three broods 

 eacli season. Besides wheat this insect breeds in 

 oats and various grasses. 



Remedies. — The destruction of volunteer wheat 

 after the worms have gotten started in it, and the 

 early planting of strips to induce them to oviposit, 

 are the best remedial measures for this insect. 



Wheat Joint- worms. 



Isosoma hordei, 1. tritici and I. grande. 



There are three nearly related species of minute 

 four-winged flies (Fig. 123, a, b) which deposit eggs 

 in wheat stems that hatch into the so-called joint- 

 worms. Accord- 

 ing to Professor 

 F. M. Webster 

 " t h e females 

 push their ovi- 

 ^w^ inositol's into the 

 stems of grow- 

 ing wheat and 

 deposit their 

 eggs singly, but 

 often several in 

 each straw. This 



g. 123. Joint-worm fly : a, female ; e, antenna IS done during 



of same ; e, abdomen of same ; 6, male; d, an- , 



tenna;/, abdomen. Magnified. the early Spring, 



and again during June, in the latitude of central 

 Indiana, the young larvae feeding upon the substance 



