F-480484 
FIGURE 54.—Adult of the 
banded hickory borer, 
Knulliana cincta. 
requires 2 years for completion. Cordwood, logs, posts and rustic 
work are frequently seriously damaged by the species. The prompt 
milling and seasoning of summer cut wood are recommended 
control practices. 
The cottonwood borer, Plectrodera scalator (F.), breeds in the 
bases of living cottonwoods and willows in the Southern States. 
The adult is 25 to 35 mm. long and beautifully marked. The 
ground color is black, but this is obscured by patches and cross 
stripes of pure white, fine hairs that surround black, hairless 
areas (fig. 55, left). 
Adults appear in late spring or early summer and feed on the 
tender shoots of young trees. These shoots often break, shrivel, 
F-519918-9 
FIGURE 55.—The cottonwood borer, Plectrodera scalator: Left, adults, 
right, larva. 
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