Vesicles and hyphae typical of vesicular-arbuscular mycorrhizae (VAM) were common in seedlings of Pseudotsuga menziesii, Abies lasiocarpa and Tsuga mertensiana growing in openings where herbaceous hosts of these fungi were common. Seedlings of A. lasiocarpa, Tsuga heterophylla, and T. mertensiana growing under closed forest canopies also had vesicles but at a much lower incidence than seedlings in the openings. The Pinaceae are generally assumed to be ectomycorrhizal, but Glomus-type colonizations occurred on the same seedlings as the ectomycorrhizae. The ecological significance of abundant VAM-type endophytes in otherwise ectomycorrhizal hosts deserves comprehensive study.