of reduced quality caused by larval tunnels. About 38 percent of the oak wood 
used for lumber, cooperage, and veneer in the Eastern United States is affected 
(321). Damage to upland oaks in the Central States can be reduced by poisoning 
borer-infested trees with a herbicide after egg laying is completed in August. Larval 
mortality occurs in a short time if the tree is deadened while they are still feeding in 
the phloem. This can be accomplished during ordinary stand-improvement opera- 
tions, because the trees selected for removal in this work are the very ones most 
likely to be heavily infested (538). 
Enaphalodes cortiphagus (Craighead), the oak-bark scarrer, breeds in the bark 
of living, mature oaks throughout the Eastern United States and westward through 
the Ozark Mountains. White and chestnut oaks are especially subject to attack. 
Adults are dark brown with patches of fine, short, gray hairs on the head, pronotum, 
and elytra and are 16 to 27 mm in length. Eggs are deposited in bark crevices in the 
spring, and the larvae feed in the bark for nearly 3 years. At the end of this period 
they bore deeper into the bark and excavate a large pupal cell in the sapwood. This 
excavation usually damages several layers of annual growth of the wood, causing a 
large black defect and the formation of scars on the outer surface of the bark. The 
presence of this defect results in considerable degrade of the lumber. The related 
species E. atomarius (Drury), breeds under the bark at the bases of dead trees and in 
the stumps of oaks, chestnut, walnut, hickory, and hackberry in southern Canada 
and throughout the Eastern United States. 
The genus Goes contains a few species that attack living hardwoods. Large 
tunnels constructed in the heartwood result in defects in lumber cut from infested 
wood. Eggs are deposited singly in oval pits chewed through the bark. Tunnels in 
the wood are excavated inward and upward and are kept open. Fibrous, granular 
frass is expelled through openings maintained at the egg scar. Life cycles vary from 
2 to 5 years, depending on species. 
The white oak borer, G. tigrinus (De Geer), the largest species in the genus 
occurs throughout the Eastern United States. White oak is its preferred host 
throughout most of its range, but various other oaks, and hickory and walnut are 
attacked occasionally. The adult is large, robust, dark brown, and from 25 to 30 mm 
long. It is irregularly covered with a dense coat of fine white hair, giving it a white 
and brown mottled appearance (fig. 129). The basal part of the elytra is roughened 
with small, black, elevated points: and there is a strong spine on each side of the 
thorax. Full-grown larvae are up to 37 mm long. 
Adults emerge in May and June and feed for 1 or 2 weeks on the bark of tender 
twigs and leaves of oaks. Eggs are deposited in niches gnawed in the trunks of 
young trees, usually from 5 to 30 cm in diameter, or in the branches of larger trees. 
The young larvae bore directly into the sapwood. Then they tunnel upward and 
penetrate deep into the heartwood, excavating tunnels up to 25 mm in diameter and 
to 25 cm in length. Each borer makes two separate holes in the tree—a small 
elongate entrance hole that it keeps open for the expulsion of frass and a round hole 
made for the emergence of the adult. The life cycle requires from 3 to 5 years, 
depending on locality (//33). 
The white oak borer is a major pest of overcup oak in the bottom lands of 
Mississippi (//34). Small trees down to 25 mm in diameter are attacked and 
seriously damaged. Trees growing on heavy clay soil with poor drainage. or where 
flooding is prolonged into the growing season, are frequently infested. It has been 
ranked as the primary pest responsible for defect in rejected staves in production of 
white oak cooperage in Ohio (322). 
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