The life history, seasonal occurrence, and adult behavior of the Columbian timber beetle, Corthylus columbianus Hopkins, was studied in 2 stands of bottomland red maple in the Georgia Piedmont. The galleries are initiated by the male, mostly in the lower trunk. Females are strongly attracted to fresh galleries from distances of 30–45 cm. The parent adults (1 male and 1–3 females) remain in the gallery throughout development of the brood. The larvae, and presumably the adults, feed on a fungus, Ambrosiella xylebori Brader, which lines channels of the gallery and brood cells. A brood of 1–26 (sex factor 0.54) emerges about 7 weeks after the gallery is started. The population goes through 3 complete generations per year with emergences in late June to late July, mid-August to mid-September, and late September to late October. The 3rd generation overwinters on the host in the adult stage and emerges from mid-May to mid-June. There was no evidence of parasitism or predation on the immature stages.
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John C. Nord (1972) studied this question.