CORN PESTS AND DISEASES 25 1 



their slender bodies, distinctly segmented and of about 

 equal diameter throughout their length. They live 

 mostly in grass lands, feeding largely on the roots. 

 Their numbers in such places are rarely sufficient to 

 produce any notable effect upon the sod. It is only 

 when concentrated in the comparatively scanty vege- 

 tation of a field of young corn in spring, or occasion- 

 ally in young wheat or other small grain, that they do 

 any very great harm. The commonest form of attack 

 on the corn, as seen by the farmer, is the burrowing 

 of the worm into the kernel. Frequently attacks in the 

 field have been so severe, particularly the first and 

 second years after the sod has been broken, as to 

 require planting a second or third time. 



These pests agree fairly well in their life history. 

 They change to the dormant pupae in the earth in July 

 or sometime in August. Some three or four weeks 

 later they transform to the brown or reddish beetles 

 known as "click beetles" or "jumping jacks." They 

 are easily distinguished by their peculiar habit of 

 springing into the air with a sudden click when placed 

 upon their backs. A large part of these fully devel- 

 oped beetles remain under ground until spring. Some 

 of them come out of the ground in the fall and pass 

 the winter in sheltered places ; the remainder emerge 

 in spring, laying their eggs mostly in grass lands. Of 

 their subsequent life history little is definitely known. 



No class of insects has had prescribed for it a 

 longer list of artificial remedies than the wireworms, 

 yet none of them is of practical value. Their injuries 

 continue practically unchecked. Even poisons of the 

 most deadly sort applied to corn previous to planting, 

 on food lures distributed through the ground, for the 

 purpose of drawing off the attention of these insects 

 from corn, have proved almost entirely valueless, 

 both in the experience of Professor Forbes and in 



