224 CORN 



ance gain in number until they destroy whole fields. The increased 

 acreage of corn on land which has been cropped for a number of years 

 favors the breeding of this insect life. 



The most disastrous insect enemies are here described and rem- 

 edies and preventives suggested. 



INSECTS INJURIOUS TO THE GROWING CROP 



THE BLACK HEADED GRASS MAGGOT (Sciara sp.) Rot- 

 ting seed corn lying in the ground, is subject to very destructive at- 

 tacks by this black-headed grass maggot. Many maggots may infest a 

 single grain and consume everything but the hull. Sprouted grain is 

 sometimes affected. Old sod land shows the majority of cases of in- 

 festation and destructive attacks. 



THE SEED CORN MAGGOT (Phorbia fusckeps, Zett.) This 

 maggot eats the interior out of the sprouting "corn kernel. Unsprouted 

 kernels, if softened, are often slightly attacked. The greatest damage 

 from this pest usually occurs in a cold wet spring. Replanting is 

 sometimes necessary. The adult is a small two-winged fly, looking 

 very much like an ordinary house fly. Definite knowledge concerning 

 the life history is not available, but Forbes, of Illinois, states that the 



larvae have been seen from May 17th to 

 June 13th, pupae from June 7th to 15th, the 

 adults emerging from June 11th to August 

 Black-headed Grass Maggot 7th. This species hibernates as a fly. A cup- 

 Searia sp. ful of kerosene added to a bucket of dry 



sand makes a mixture which, when placed 

 in small amounts at the base of the corn plant, prevents the adult fe- 

 male from depositing her eggs. Kainit and nitrate of soda act in a 

 similar way when moistened. Any injured plants should be destroyed 

 immediately. 



WIREWORMS. Drasterius elegans. If the seed fails to come or 

 the corn plant suddenly presents a withering appearance when from 10 

 to 15 inches high, it is very probable that the wire worm is present, 

 especially if the ground was in grass the year before, or two years 

 previous. 



The wire worm is of a reddish brown color, varying from yellowish 

 to reddish. It varies in length from half an inch to an inch and a half. 

 Its body is slender, carrying about same width throughout and bear- 

 ing very few hairs. The surface is hard and crust-like. The body has 

 13 segments. On the three segments just posterior to the head are 

 six pairs of short, stout legs, and on the under surface of the thirteenth 

 segment is a single leg, sucker-like in appearance. 



The eggs which produce the wire worm are laid in grass lands in 



