Records of Megachile inermis Prov. in trap-nests are given in order to supplement previous reports on the nesting biology of the species. In Saskatchewan, Peck and Bolton (1946) did not obtain nests in 1943 with 1/4-inch holes bored in logs, but were successful in 1944 with 5/16-inch holes. The cells in 14 nests averaged 4.2, range 2 to 7, and their rearings produced 10 males and no females. In Manitoba, Stephen (1955) associated the nesting of M. inermis with burnt-over or waste poplar. The bee utilized the poplar after the trees had decayed sufficiently to permit the bee to burrow into it. He found no indication of nesting in borer tunnels, but reported that the bees themselves excavated tunnels from a crack or crevice or the exposed end of a log. Stephen (1956) described the excavating activity of the bee in poplar, and reared 3 males from cells transferred to glass tubes.