Morphology, Anatomy and Histochemistry of Fagus grandifolia Ehrh. (North American Beech) Ectomycorrhizas

Five distinct ectomycorrhizal morphotypes were recognized on root systems of Fagus grandifolia collected in a maple‐beech woodlot. Three morphotypes showed extensive root branching whereas two had limited root branching. One morphotype, a bright orange, smooth type, was studied in detail anatomically. A compact mantle with few emanating extraradical hyphae covered the root apex of each mycorrhizal lateral. A Hartig net extended around epidermal and hypodermal cells. Roots were mostly diarch and a single‐layered endodermis and a biseriate hypodermis with the inner hypodermis having suberized walls were present in all specimens examined. The mantle, and to a lesser extent the Hartig net, stored lipids, polysaccharides and proteins.