32 2 ECONOMIC ENTOMOLOGY 



wash in early June to trunks; apply protectors to trunk; spray with 

 arsenical to kill adult. Woodpeckers destroy large numbers of the 

 larvae. 



Saperda tridentata Oliv. is the well-known elm-borer. The grub 

 girdles the tree by burrowing under the bark. 



Raspberry Cane-borer {Oberea bimaculata OHv.). Adult. — A 

 slender black cerambycid beetle, 3^^ inch long; pro thorax yellow, with 

 two or three black spots; antennae long, body cylindrical; June. A 

 native American insect. 



Eggs. — Large, elliptical, yellow. Egg placed in pith of tip of cane 

 in a slit between two ring-like cuts about an inch apart. Hatches in 

 a few days. 



Larva. — A dull yellow grub with a small dark-brown head; i inch 

 long; body cylindrical and segments connected. Burrows downward 

 in the pith, often opening at surface of stem. Hibernates near base 

 of stem as a larva. 



Pupa. — -Formed in burrow in spring. Perhaps this insect requires 

 two years to complete its stages. Wilting occurs in July-August. 



Control. — Cut off and destroy the wilted canes as soon as observed. 



Giant Root Borer {Prionus laticollis Drury) . A dull. — A large pitchy- 

 black, long-horned beetle; thorax with three teeth on margin ; wing-covers 

 thickly punctate. 



Larva. — ^Two to three inches long; yellowish- white; a small, horny, 

 reddish-brown head with hard dark jaws; three years; matures in 

 June-July, boring into roots of black berry, grape, apple, and 

 cherry. 



Locust Borer (Cyllene robinia Forst.). — Heartwood of infected trees 

 shows longitudinal galleries often so numerous as to give honey- 

 combed appearance to the wood. 



Adult.— A black long-horned beetle, with three straight yellow 

 bands across thorax and five broken or irregular yellow bands across 

 wing-covers; ^4 inch long; found on golden rod in August-October. 



Eggs. — Snow-white; deposited in the fall in crevices in the bark 

 of black locust trees; hatch in 8-10 days. 



Larva. — Makes winding tunnels deep into the wood; matures in less 

 than a year; ^ inch long, dull white, somewhat flattened and club- 

 shaped. Winters as a young larva in the soft inner bark. 



Pupa. — Formed in July-August and stage lasts 4 or 5 weeks. 



