This fan-shaped mushroom grows both wild and cultivated in close clusters, often on rotting tree trunks. They`re also called oyster caps, tree mushrooms, tree oyster mushrooms, summer oyster mushrooms, pleurotte and shimeji. The cap varies in color from pale gray to dark brownish-gray. The stems are grayish-white. The flavor of raw oyster mushrooms is fairly robust and slightly peppery but becomes much milder when cooked.