6 



Oklahoma Agricultural Experiment Station 



Pupa. Pupation takes place in the tunnel. This stage lasts from 

 ten days to two weeks. About a day before the pupa transforms to 

 the adult stage the yellow crossbars begin to appear on the thorax 

 and wing covers. From specimens studied, it was learned that the 

 insects do not always emerge from the trees immediately after trans- 

 forming from pupae to adults, but remain for some time in the 

 tunnels. 



CONTROL 



Disease. Oftentimes dead larvae in various stages of develop- 

 ment have been found in tunnels. It seems that this may have been 

 due to disease, but thus far investigations do not warrant a definite 

 conclusion. 



Insect Parasites. The wheelbug (Prionidus cristatus) is known 

 to feed on the adults. It is not instrumental, however, in controlling 

 an infestation of these beeltes. The enemy grasps the beetle and 

 inserts its proboscis into the body of its host and feeds on the vital 

 fluids. 



Clean Cultivation. Since the beetles feed mainly on the pollen 

 of the goldenrod it would be well to destroy all such plants. By re- 



ffffftP 



I'igure 3 Above, Larva in tunnel; below, cross-section of tree trunk showing work 

 of larvae; natural size 



