About Pleurotus populinus O.Hilber & O.K.Mill.
Pleurotus populinus, formally described as Pleurotus populinus O.Hilber & O.K.Mill., produces fruit bodies with caps ranging from oyster shell-shaped to fan-shaped. Caps measure 4–19 cm (1.6–7.5 in) across and 4–13 cm (1.6–5.1 in) wide. The cap margin is initially rolled inward, and develops a finely scalloped texture as the mushroom ages. Cap color varies from ivory white to pinkish buff to orange-grey. The gills are somewhat decurrent, extending only a short distance down the mushroom’s stipe. Gills are 3–10 mm broad, white to cream in color, and have two sets of intervening short gills called lamellulae. This species produces a buff spore print. Its spores are thin-walled, with a narrowly elliptical to oblong shape, and measure 9–15 by 3–5 μm. The four-spored club-shaped basidia measure 20–27 by 5–6 μm. Fruit bodies of Pleurotus populinus grow alone, in scattered groups, or in large overlapping clusters, on rotting stumps, logs, and limbs of hardwood trees. Aspen and black cottonwood are its preferred growth substrates. The species occurs in northern United States, Canada, and mountainous regions of western North America. It is common within this range, and produces fruit bodies in June and July.
