Pleurotus populinus

Description

Pleurotus populinus is a gilled fungus native to North America. It is found on dead wood of aspen and cottonwood trees (genus Populus). Although morphologically similar to Pleurotus ostreatus and Pleurotus pulmonarius, it is a distinct species incapable of cross-breeding. Grows in clusters. Gills run down the stem. White, Tan or Brown at full maturity.

It is an edible mushroom with a mild taste. It is known to be high in protein & fiber, iron, zinc, potassium, phosphorus & selenium, calcium, folic acid, vitamins B1, B3, B5 & B12, vitamin C & vitamin D.

Oysters have a very unique smell that is hard to describe. They need to be collected when very fresh if they are to be eaten. They get infested with bugs rather quickly. This is also one of the easiest mushrooms to cultivate. If you have ever bought fresh oysters from the supermarket you should be able to identify these right away.

Common names: Aspen Oyster.

Mushroom Identification

1. Cap

   5–25 cm in diameter, not round, but fan- or shell-shaped with an off-center stem, at the side of the cap. Starting rounded, but with age becoming flat or wavy. The color is white to gray-brown. The surface is smooth and dry.

2. Gills

   Decurrent, descending the stem, well-spaced to crowded, white to buff.

3. Stem

   0.5–3 cm long x 0.5–2 cm wide, short or almost absent, usually lateral rather than central, pale-colored. The surface is smooth, sometimes with hairs or fluff at the base.

4. Spores

   10–14 x 5.5–7 µm, smooth.

5. Spore Print

   Whitish.

6. Habitat

   Fruiting in shelf-like, overlapping clusters or singly, on branches, trunks and logs of deciduous trees such as alder (Alnus sp.), cottonwood and aspen (Populus spp.), and willow (Salix sp.). Easily cultivated on all kinds of substrates (coffee grounds, saw dust, straw bags, wood chips etc.), and therefore commercially grown. It is a common species in its range, where it fruits in June and July.

7. Distribution

   In northern and mountainous regions of North America, also Europe and Asia.

History

The species was first described scientifically by mycologists Oswald and Orson K. Miller in 1993 with a provisional name. This original naming was invalid according to several sections of the International Code of Botanical Nomenclature, so it was republished in 1997.

Photo sources:

Photo 1 - Author: Jim Tunney (Jim Tunney) (CC BY-SA 3.0)

Photo 2 - Author: Phil Yeager (gunchky) (CC BY-SA 3.0)