
Appearance
With concentric circles of many colors, it highly resembles "Trametes versicolor", turkey-tail, and is thus called the 'false turkey-tail'. The stemless fruiting body is shell-like and grows 1–7 cm high. It is tough and inedible. It grows on tree bark. This fungus is native to North America, where it is widespread and grows all year round.It gets its name 'false turkey-tail' because it mimics "Trametes versicolor". They can be distinguished as "T. versicolor" has numerous pores on the underside of its fruiting body, unlike "S. ostrea". Also, "S. ostrea" is more red in color. Factors such as its relatively large size and shell-like body distinguish it from other members of the genus "Stereum".
The fruiting body is 1–7 cm wide, shaped like a shell and thin. Its surface can be hairy or smooth at the very first, growing smoother with age. The concentric zones can have a variety of colors - ranging from yellowish red to a dark brown. If algae grow on it, the color can change to green. The flesh is very thin and too tough to eat, with no distinct odor. The fungus lacks a stem. The underside is smooth and lacks pores, white to gray or a reddish-brown shade in color. The spore is white, and measures 5.5–7.5 micrometres x 2–3 μm.

Distribution
"S. ostrea" is saprophytic in nature. It is a plant pathogen, growing on hardwood tree barks, especially oak, and decaying parts. It leaves white deposits in these places. It grows individually, but in a dense manner. "Phlebia incarnata", another fungus, is most commonly found growing alongside or even intermingled with this species. This fungus can be parasitized by jelly fungi. It grows all year round and is widespread in North America.
Habitat
"S. ostrea" is saprophytic in nature. It is a plant pathogen, growing on hardwood tree barks, especially oak, and decaying parts. It leaves white deposits in these places. It grows individually, but in a dense manner. "Phlebia incarnata", another fungus, is most commonly found growing alongside or even intermingled with this species. This fungus can be parasitized by jelly fungi. It grows all year round and is widespread in North America.References:
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