Abstract
Thirty-one species of vascular plants commonly occurring in the Boreal Forest Region of northeastern Ontario were examined for the presence of mycorrhizae. Two species were ectomycorrhizal, 3 both ecto- and endo-mycorrhizal, and 15 endomycorrhizal. Two species of Ericaceae had ericoid mycorrhizae and one had both ericoid and arbutoid mycorrhizae. Eight species, unexpectedly including three species of Rosaceae and two of Saxifragaceae, completely lacked mycorrhizae. The significance of the findings concerning the Betulaceae, Fraxinus, the Ericaceae, Rosaceae, and Saxifragaceae are discussed, as is occurrence of Cenococcum-type infections among the species.