Ectomycorrhizae of Douglas-fir and western hemlock seedlings outplanted on eastern Vancouver Island

Ectomycorrhizal colonization of container-grown Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and western hemlock (Tsugaheterophylla (Raf.) Sarg.) seedlings was determined in a container nursery near Nanaimo, British Columbia, and after one growing season under a range of field conditions on eastern Vancouver Island. The percentage of Douglas-fir and western hemlock short roots colonized by ectomycorrhizal fungi in the nursery was highly variable, but over 99% of the ectomycorrhizae were formed by Thelephoraterrestris Ehrh.:Fr. Between 72 and 93% of the new roots were ectomycorrhizal after one field season, and Thelephoraterrestris remained the dominant fungus in most cases. Rhizopogonvinicolor like ectomycorrhizae were also common on new roots of Douglas-fir. Cenococcumgeophilum Fr. was less common. Douglas-fir seedlings formed 33 morphologically distinct ectomycorrhizae on eight sites within one growing season in the field. Western hemlock formed nine types on a single site.