120 INSECTS OF ECONOMIC IMPORTANCE 



Cutworms (several species) 

 There are several species that injure corn as 

 well as wheat. They are apt to be more abundant 

 and severe on corn planted on sod. They have been 

 discussed under wheat pests. 



White grubs (Phyllophaga sps.) 

 These are injurious to many crops, notably straw- 

 berries, wheat, corn and oats. They were discussed 

 under strawberry pests. 



Sod webworms ^^ (Cranibns sps.) 

 Order — Lepidoptera 



These are the larvae of a family of small moths of 

 the family Cramhidcc; the larvae are about one-half 

 inch in length and pinkish-red or brownish; they 

 work at first underground gnawing away the outer 

 surface of the stem and roots ; later, they burrow up 

 the center of the stem ; they also sometimes eat the 

 leaves; usually the webworms will be found just 

 below the surface each in a retreat formed by 

 loosely webbing together a mass of dirt ; within the 

 mass is a silk-lined tube and within this a caterpil- 

 lar; so far as known all of the species pass the 

 winter as caterpillars not full grown; some have 

 one generation and some two each year. 



Control — Break land early in fall or as late as 

 possible in spring to destroy larvae. 



The corn billbug ^^ (Sphenophorus callosus) 

 Order — Coleoptera 



There are several species of snout-beetles known 

 as ''billbugs" that injure corn by eating cavities in 

 the stem close to the ground or just below the sur- 

 face of the soil; the grubs also burrow inside of the 



10 Forbes— 23rd Kept. 111. State Ent, 1905. 



11 Satterthwaite— U. S. Dept. Agr., Ear's' Bull, 1003. 



