Eight hardwood forest species were grown in fumigated soil without vesicular-arbuscular mycorrhizal (VAM) fungi or in soil infested with either Glomus fasciculatus (GF), a mixture of Glomus mosseae and G. etunicatus (GM), or a mixture of several fungal species in the genera Glomus and Gigaspora (GG). With the exception of sugar maple, VAM development increased stem weight of seedlings by 2- to 80-fold over nonmycorrhizal controls. Root weight of all seedlings was increased by 4- to 70-fold by VAM. Generally, GF stimulated more seedling growth than other fungi. Laboratory assays of the root samples indicated that feeder root infection by the fungi varied from 55 to 85 percent, but generally there were no significant differences among the VAM treatments within tree species. Differences among hosts were observed in the amount of hyphae, arbuscules, and vesicles produced by the fungi, which could be attributed to growth and development characteristics among hosts and VAM fungi. The data suggest that high-quality seedling stock of these hardwood tree species can be obtained in nurseries where cultural practices in the nursery encourage VAM development
