Based on emergence data, Eriotremex formosanus (Matsumura), an exotic horntail established in the southeastern United States, was found to be 1) significantly more abundant in Quercus nigra L. than in Liquidambar styraciflua L. and absent from Pinus taeda L., 2) significantly more abundant in snags than logs, 3) similarly abundant in upland pine-dominated forests and bottomland hardwood-dominated forests, and 4) present at all heights along the bole but not in branches. Captures of E. formosanus in flight intercept traps positioned next to snags, logs and living trees of each tree species support these findings.