204 



INSECTS AFFECTING FIELD CROPS 



It closely resembles some of the cut-worms and is, in fact, a member 

 of that family. The moths are among the most common of the 

 so-called " millers." The front wings are clay or fawn colored, 

 speckled with black scales. The hind-wings are somewhat lighter, 

 with blackish veins and darker margins. 



Life History. There are two or three broods a year. The 

 winter is passed in the larval stage. The moths first appear in 

 early spring. The female lays from ten to fifteen eggs at a time 

 near the unfolded bases of the leaves of grass. One female may 



FIQ. 219. The western corn-root worm, egg, larva, pupa, imago. (After Forbes.) 



lay seven hundred eggs. Ten days are required for hatching and 

 from three to four weeks for the larvae to become full grown. 

 When mature, the caterpillars enter the ground, transforming into 

 pupae, and the adult moths emerge in two weeks and immediately 

 lay eggs for the next generation. 



Injury. As their name indicates, these caterpillars frequently 

 travel in large numbers in search of food. They feed entirely at 

 night, and whole fields of corn or other grain may be destroyed 

 before their presence is realized. Grasses form their favorite food, 

 and the heads of grasses are frequently cut off. Various garden 

 crops are also injured. Clover, however, appears to be almost 



