334 INJURIOUS INSECTS, WITH TREATMENT 



ROOT-BEETLE (Ligyrus rugiceps). This insect occurs throughout 

 the lower Mississippi valley and the southern states generally as far 

 north as North Carolina. As the name implies, the beetle 

 infests the roots of the cane plant. The insect hibernates 

 in the advanced larval or the pupal stages, and the adult 

 appears in the spring. The injury to the cane is accomplished 

 by the adult eating into the young shoots just below the surface 

 of the ground. From this point the insect works downwards 

 to the roots, where the eggs are laid. The larva develops about 

 the roots. In the case of young shoots the injury is sufficient to 

 practically sever the shoot from the mother cane or stubble. This 

 kills out the heart of the young plant, and unless the cane suckers 

 well, the stand is seriously affected. 



Treatment. If the stubble cane is off-barred in the spring 

 and the soil kept away from the young cane as late as the conditions 

 will allow, much injury from the root beetle will be avoided. Fre- 

 quent cultivation of the plant cane will disturb the beetles in the 

 soil and lessen their chance of attacking the cane. No great 

 amount of vegetable matter should be plowed under on those 

 areas where the root beetle is abundant, since this favors the de- 

 velopment of the larvae or " white grubs." The headlands 

 and ditch banks should be kept clear of grass, since the beetle de- 

 velops in these situations bordering the cane-fields. In districts 

 where freezing temperatures occur, late fall plowing will turn out 

 many of the grubs, and they will perish from exposure. During 

 an attack, it is often profitable to have children follow and collect 

 the beetles behind the hoe gangs. 



Sumac. APPLE-TREE BORER. See under APPLE, p. 308. 

 JUMPING SUMAC-BEETLE (Blepharida rhois). Larva, half-inch long, 

 dull greenish yellow, feeding on leaves ; two broods. 



Remedy. Arsenicals. 



Sweet-potato. SAW-FLY (Schizocerus ebnus and S. privatus). Small 

 larva about one-fourth inch long, working upon the leaves. The 

 fly is about the size of a house-fly. 



Remedies. Hellebore and arsenicals. 



ROOT-BORER (Cylas formicarius) . A whitish grub one-fourth inch 

 in length, burrowing through the tubers. * 



Preventive. Burn infested tubers and the vines. 



