234 CORN 



the onward march of the chinch bug, a strip about lo feet wide may be 

 plowed between the corn and the infested field. A part of this, at 

 least three feet in width, should be very finely pulverized. A furrow 

 ■should then be made in this pulverized strip, making the sides as 

 vertical as possible. In the bottom of this eight-inch furrow, at in- 

 tervals of lo feet, dig holes at least two feet deep. As the line of 

 march is intercepted by this ditch the invaders fall to the bottom, are 

 unable to climb the other side, and finally fall into deeper holes. A 

 short log may be dragged up and down this trench by a horse, thus 

 destroying the pests as they enter. Kerosene poured upon the bugs 

 in the deeper holes kills them effectively. Another resort is to place 

 a line of tar between the first trench and the corn field. If this is 

 renewed twice or three times daily it is very effective. 



When the chinch bugs are on the plants they may be destroyed 

 by spraying with kerosene emulsion made as follows : 



Dissolve half pound of soap (hard or soft) in a gallon of water 

 by boiling; then remove from stove and stir thoroughly; add two 

 gallons of kerosene; mix thoroughly by pumping this fluid back 

 into itself by means of a common spray pump. Before application 

 add fifteen quarts of water to each quart of mixture. This spray 

 should be applied before ten o'clock in the morning, if possible. 

 Enough should be applied so that the insects will be washed off and 

 will be seen floating in the emulsion at the base of the plant. As an 

 economical process this cannot be recommended on a large scale. 



ARMY WORM (Heliophila unipuncta) The army worm be- 

 longs to a large family of insects known as the Noctuidae. Grass 

 lands being its natural home, it is present to a limited extent every 

 year. The mature insects are dull brown moths, having a peculiar 

 white spot in the center of each anterior wing, from whence comes 

 the name "unipuncta." The body is about three-fourths of an inch 

 in length in the adult. The eggs, which are usually laid in the termi- 

 nal leaf sheath of grasses and grains, are small, globular, and white. 

 Dr. Riley* found eggs deposited in strawstack bottoms, hay ricks, old 

 corn shocks, and even two-year-old corn stalks lying on the ground 

 in the meadow. His estimate of a single female laying from 500 to 

 700 eggs accounts for the rapid increase of the worms under favorable 

 conditions. These eggs hatch in from 8 to 10 days. After feed- 

 ing on anything of succulence about it, the larva is full grown in 

 25 to 30 days, attaining a length of i 1-2 inches. When young they 

 travel like a measuring worm, are dark, naked caterpillars with longi- 

 tudinal stripes running the full length of the body. A very marked 



*U. S. Department of Agriculture Report 1881-1882, P. 90-91. 



