170 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



beans, or whatever food-plants are available, and hatch in three to 

 five days, depending upon the temperature. 



The caterpillars of the first generation often attack corn when 

 about knee-high, feeding in the axils of the tender leaves, so that 



when the leaves unroll 

 they bear horizontal rows 

 of holes. The caterpil- 

 lars are exceedingly vari- 

 able in color, being from 

 a light green through 

 rose color and brown to 

 almost black, and either 

 striped, spotted or per- 

 fectly plain. They be- 

 come full grown in about 

 2J weeks and are then 

 about 1J to 1J inches 

 long. When done feed- 

 ing the caterpillar bur- 

 rows 2 to 5 inches into 

 the soil near the base of 

 the plant. A cell is then 

 constructed which runs 

 back to within a half 

 inch of the surface of the 

 soil, so that the moth 

 may readily push off this 

 surface soil and escape. The burrow finished, the larva retires 

 to the bottom of the cell and there molts and enters the pupal. 

 The pupa is four-fifths inch long, shining reddish-brown. 

 During the summer the moths emerge about two weeks later, 

 but the last generation in the fall passes the winter in the pupal 

 stage. Thus the complete life cycle from egg to adult moth 

 requires slightly over a month in midsummer, and from six to 

 eight weeks for the spring and fall broods. 



The second generation of moths appears about the middle 

 of July in the latitude of Delaware and Kansas. In the far 

 South the second generation of moths appears when corn is com- 



FIG. 146. Corn ear-worm or cotton boll- 

 worm (Chloridea obsoleta): a, adult moth; 

 6, dark full-grown larva; c, light-colored 

 full-grown larva; d, pupa natural size. 

 (After Howard, U. S. Dept. Agr.) 



