CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 



341 



and truncate at tip; pronotum strongly bent downward in front so 

 as to be nearly vertical. Male wingless, smaller than female, and with 

 a curious, humped back. June. 



Eggs. — ^Laid free in galleries in June. 



Fig. 223. — Clover root borer (Hy- 

 lastinus obscurus). Natural size at 

 right. {After Webster, U. S. Bur. Ent.) 



Fig. 224. — Larva or grub 

 of the clover root borer. En- 

 larged. {After Webster.) 



Larvce. — Feed on fungus growing on walls of tunnel; mature late in 

 season. 



Pupa. — Formed in tunnels and adults emerge through entrance 

 hole cut by mother beetle. 



Clover Root Borer {Hylastinus obscurus Marsh). 

 — Adult. A small dark brown cylindrical hairy scoly- 

 tidid beetle, 3^fo ii^ch long; wing -co vers coarsely 

 punctate (Fig. 223). 



Eggs. — Minute, white, elliptical and shining. 



Larva. — A white stout footless grub with yellow 

 head and brown mouth-parts; % inch long (Fig. 224). 



Pupa. — White, with a pair of spines at top of head, 

 and another at tip of abdomen (Fig. 225). 



Life-history. — -There is but one brood each year. 

 The adult winters in the clover roots, and lays her 

 eggs during May and June in the crown or on the 

 sides of the root. The larvae tunnel the root, and 

 mature in July; the pupae transform to adults be- 

 fore October ist. 



Control. — Flow up infested clover fields after the hay is taken off; 

 break up clover sod after taking one crop. 



Forest Bark -beetles {Dentroctonus spp. chiefly). — (Consult bulletins 



Fig. 225. — 

 Pupa of the 

 clover root borer. 

 Enlarged. {After 

 Webster.) 



