Ostreatus white spongy rot
Damage, symptoms and biology
The fungus causes decay of the sapwood, affecting mainly the vertical part of the trunk. The damage is not severe and has little or no physiological effect on the trees. The infection is initiated when spores colonize a small wound on the trunk. Once the infection is well established in the outer sapwood, the fruiting body develops and becomes visible. The fruiting body, which bears the spores, is convex-shaped and flattens to a wavy margin; the upper surface is smooth and slightly downy near its attachment to the stem. The colour ranges from yellow-white in young specimens to gray-brown in the oldest ones.
The oyster mushroom fruiting body is edible and has a mild flavour when harvested young. Be sure to carefully identify mushrooms before eating them.
Canadian Forest Service Publications
Information on host(s)
American beech, birch, cherries / plums, elms, hickory, juniper, maple, oaks, poplars / aspens / cottonwoods