RASPBERRY, BLACKBERRY AND DEWBERRY INSECTS 335 



The Blackberry Crown-horer 

 Bemheda marginata Harris 



Blackberries and raspberries an^ often injured l^y the cater- 

 pillar of a clear-wing moth which burrows in the roots and crown. 

 This insect is generally distributed through- 

 out the Northern states and Canada and' 

 has been recorded from New Mexico. 



The parent moth has an expanse of 1 to 

 1| inches; the wings are transparent, with 

 a brown margin, and the fore wings have 

 a narrow, transverse brown band on the 

 outer third ; the abdomen is black crossed 

 by four bands of bright yellow; in the 

 female the last segment is yellow, in the 

 male, black mixed with yellow. The 

 moths emerge during August and early 

 September and the female deposits her 

 oval, reddish-brown eggs, yV inch in length, 

 singly on the under side of the leaves 

 near the edge. Each female lays about 

 140 eggs. 



On hatching, the caterpillar is about yV 

 inch in length and is nearly white, with 

 a brownish head. It crawls down the 

 stem and goes into hibernation curled up 

 in a small cavity beneath a blister-like 

 elevation of the bark of the cane just below 

 the surface of the ground or may hibernate in crevices at the 

 base of the canes or under flakes of bark. In the spring the 

 caterpillars enter the roots or the base of the cane where they 

 generally burrow just beneath the bark, girdling that part of 

 the plant. By the second winter the larva are J to f inch in 

 length. They hibernate in their burrows, and the following 



Fig. 294. — The 

 blackberry crown-borer 

 in its burrow at the 

 base of a plant. 



