INSECTS of...Hardwood Branch and Stem

Common Name:	CARPENTERWORM Entrance hole to a carpenterworm's gallery in an oak tree.
Species	Prionoxystus robiniae
Common Hosts:	Cottonwood Populus spp. Oaks Quercus spp. Willows Salix spp. Other hardwoods
Description	Adult -- female moth light grayish-black body and front pair of wings, wingspan approximately 75 mm; male moth smaller and darker. Larva -- size variable, approximately 65 mm long when mature; brown head, reddish-pink to greenish-white body.
Importance	Severe infestations can decrease the rate of growth of a tree. The large holes provide an ideal entrance for decay pathogens. Trees may be mechanically weakened and suffer wind breakage.
Signs of Infestation	Sapstaining on bark. Wood chips and pellets at base of tree. Rough elongate holes in bark on trunk. Brown pupal skin protruding from holes.
Control	Identify and remove highly susceptible trees. Minimize injuries to trees; promote health. Use an approved insecticide to minimize possibility of infestation.

Bulletin No. 196-A | Printed October, 1983 | Contact the Forest Health Section

CARPENTERWORM