Domain: Eukarya
Kingdom: Fungi
Phylum: Basidiomycota
Class: Agaricomycetes
Order: Agaricales
Family: Pleurotaceae
Genus: Pleurotus

Pileus: 5-25 cm broad, fan or oyster-shaped; Natural specimens range from white to gray or tan to dark-brown; margin inrolled when young, smooth and often somewhat lobed or wavy. Flesh white, firm, varies in thickness due to stipe arrangement.
Lamellae: Gills are white to cream, descend stalk if present. If so, stipe off-center with lateral attachment to wood.
Spores: The spores form a white to lilac-gray print on dark media. Spores 7.5-9 × 3.5-4.5 µm, smooth, elliptical, nonamyloid.
Stipe: Often absent. When present it is short and thick.
Taste: Mild
Odor: Often has a mild scent of anise.

Worldwide.

The Oyster Mushroom is widespread in temperate and subtropical forests throughout the world. It is a saprotroph that acts as a primary decomposer on wood, especially deciduous, particularly beech and hardwoods that grow near creeks.

The mushroom usually is not fussy where it grows, however it does not like to grow near stinging nettles. This is probably due to the high acidity of the nettles.

There are no poisonous lookalikes that grow in North America, however Omphalotus nidiformis is a toxic lookalike that is found in Australia and Japan.

It is also likely that Pleutous ostreatus is a species complex that will eventually be broken up into a set of distinct taxa.

An excellent edible that commercially grow and sold in many parts of the world.

Oyster mushrooms are a natural source of statin drugs, specifically, isomers of lovastatin.

Studies have shown that they typically contain 0.4% to 2.7% statins on a dry weight basis. A number of studies on lab animals have shown that adding Pleurotus to the diet can reduce cholesterol under some conditions.

Oyster mushrooms contain a small amount of arabitol which can cause gastrointestinal distress in some people. Arabitol is a sugar alcohol similar to xylitol, manitol and sorbitol; these sugar alcohols are widely used food additives and can also have laxative effectives in susceptible individuals.

References:
The content for this page is largely adapted from the Wikipedia article on the Oyster mushroom. See that article for detailed references, authorship and references.

“Common Name: Oyster Mushroom”