This ovitrap study examined the effects of altitude above sea level, tree species, and tree trunk diameter on the distribution of eggs of the 2 tree hole mosquitoes, Aedes hendersoni and Ae. triseriatus. Only tree species and trunk diameter affected the distribution significantly. Aedes hendersoni eggs were found more frequently associated with trees of border and sunny habitat, while Ae. triseriatus eggs were more frequently found in association with trees of mesic habitat. Oviposition of Ae. hendersoni occurred more often at trees with smaller diameter at breast height than did Ae. triseriatus. These differences in ovipositing frequency appear to be related to the microhabitat associated with different sample sites.