WORK OF CORN ROOT WORM 247 



be had by keeping the ground in corn but for two years in succession 

 and then rotating with small grains and legumes. By practicing a 

 proper system of crop rotation, the ground will be more productive. 

 This is also the very best method of combating all insect pests so 

 injurious to our farm crops. 



THE GRASSHOPPER (Acrididae). The injury to corn due to 

 hoppers is usually confined to the border rows near a pasture or 

 meadow. The grasshoppers devour the silks and eat away the husks, 

 thus preventing pollination. The lower leaves may be consumed in 

 some cases. The seriousness of this pest is more marked in certain 

 years. The "grasshopper dozer" has proved a very effective means 

 of eradication. This consists of a shallow pan filled with kerosene 

 placed upon a sled or low wheels and protected in the rear by an up- 

 right canvas. The molested grasshoppers jumping against this can- 

 vas drop immediately into the kerosene and are killed. 



*"The Criddle Mixture has proved effective for poisoning grass- 

 hoppers in Illinois and in Canada. This mixture is composed of one 

 part, by measurement, of paris green to 120 parts of horse droppings, 

 preferably fresh ; or about a gound of paris green to half a kerosene 

 barrel of the droppings, with a pound of salt in addition if the material 

 is not fresh." 



THE EAR WORM (Heliothis armiger). The ear worm is also 

 known as the corn worm, cotton boll-worm, tomato worm, and to- 

 bacco bud worm. It varies in color from a light green to a brown 

 with light and dark stripes running lengthwise of the body. Its legs 

 are dark, head yellow, body slender and nearly hairless. It is noticed 

 most especially when feeding on the corn ear just beneath the husks. 

 This worm may feed on the leaves by making small holes here and 

 there. Early in the season it feeds on garden truck. The furrow 

 made on the ear of corn begins at a round hole in the husk and extends 

 spirally in a longitudinal direction, often reaching half way down the 

 ear. Decay usually sets in at once and the damage is accelerated in 

 this manner. Sweet corn is most commonly infested. 



There are 3 generations in a single season. They hibernate 

 in the pupa stage. The moth comes forth in early April and soon 

 begins to lay eggs. Each female may produce from 200 to 300. The 

 eggs soon hatch and the caterpillars reach their maturity in 3 

 weeks, after passing through six moults. Then they pupate. Three 

 generations go through this cycle in one season. The larvae of the 



*Page 395 of Bulletin 95 of Illinois. 



