Red oak borer (Enaphalodes rufulus)
White oak borer (Goes tigrinus)
U.S. Department of Agriculture, Forest Service. 1979. A guide to common insects and diseases of forest trees in the northeastern United States. Northeast. Area State and Private Forestry, Forest Insect and Disease Management., Broomall, PA. p. 123, illus.(USDA Forest Service, Northeast Area State and Private Forestry Publication. NA-FR-4)
These two long-horned, wood-boring beetles annually account for enormous losses within the hardwood timber industry. True to their names, preferred hosts are species within the red oak group and white oak group, respectively.
Females lay eggs in pits chewed through the outer bark or within bark crevices. In a few weeks the eggs hatch, and the larvae bore directly into the phloem. Eventually they tunnel into the wood, destroying its sawtimber value. Adult red oak borers are light brown, 1 inch long, and have an almost even distribution of fine, white hairs. White oak borers are dark brown, about 1¼ inches long, and are mottled with patches of white. Larvae of both are full-bodied, cream to yellow, and larger at the anterior. The life cycle of the red oak borer requires 2 years; most adults emerge in odd-numbered years. The life cycle of the white oak borer requires 3 to 5 years, depending on location.