ENEMIES OF THE CORN CROP 233 



practiced, so that corn is grown on the same soil only once 

 in three or four years, there will be no chance for the 

 insects to increase. The trouble invariably comes from 

 planting corn after corn, except on river bottoms, which 

 are overflowed several times during each year. I have 

 seen corn grown on the bottom lands along the Wabash 

 river near LaFayette, every year for the past twenty- 

 eight years, and I have never known a crop to be in- 

 jured by this insect. But on the upland, black prairie 

 and muck soils, where corn is the principal crop that can 

 be successfully grown, this insect is sure to give trouble. 

 On such land oats and grass should rotate with corn. 



The corn root-aphis is a different proposition, as it 

 belongs to the suckling class or true bugs, but like the 

 other, it does its work on the roots under ground, and 

 so is difficult to reach. These lice are usually attended 

 by ants, as the latter are very fond of the "honey dew" 

 which is given out by the lice through two little tubes, 

 which are situated on the back of the adult insect. The 

 ants even gather up the aphis eggs and store them in 

 their nests where they are cared for during the winter. 

 During April and May, as soon as the smart-weed and 

 fox-tail grass make their appearance, these eggs begin to 

 hatch and the ants carry their young wards and colonize 

 them on the roots of these plants. As soon as the young 

 corn plants are well started, the second brood of lice be- 

 gins to appear and the ants transfer them to the corn 

 roots where they continue to increase with great rapidity, 

 and to suck the life out of the corn plants. 



It is evident from the above, that the land seldom be- 

 comes infested with these lice until the second or possibly 

 the third corn crop. If, therefore, a three or four-year 

 rotation is practiced in which corn appears only once, 

 there will be but little, if any, damage done by the aphis. 



Then, too, the proper fertilization of the soil is of great 

 importance, as it enables the corn to make a crop in spite 



