Hericium abietis

Hericium abietis, commonly known as the bear's head or the western coral hedgehog, is an edible mushroom in the tooth fungus group. It grows on conifer stumps or logs in North America, producing a cream white fruit body up to tall and wide. It fruits from after the start of the fall rains to mid-season.
Taxonomy.
The species was first described as "Hydnum abietis" by American botanist James Robert Weir in 1931. Weir collected the type specimens in 1916, near the Priest River in Idaho. Kenneth Archibald Harrison transferred it to the genus "Hericium" in 1964. The mushroom is commonly known as the "bear's head" or the "western coral hedgehog".
Description.
The fruit body forms a compact, branched mass with long spines hanging down. The branches originate from a single, thick, tough base. The color of the fruit body ranges from white to creamy, light yellowish, to salmon-buff. The hanging spines are usually long, although some may be as long as ; they are soft and brittle, and typically grow as clusters at the tips of the branches. Typically, fruit bodies have dimensions in the range of tall and wide, but they have been known to attain massive sizes; one noted specimen was about .
"Hericium abietis" produces a white spore print. Spores are spherical or nearly so, smooth to slightly roughened, amyloid, and measure 4.5–5.5 by 4–5 μm. The hyphae are monomitic (consisting of only generative hyphae), and they have clamp connections.
Similar species.
"Hericium erinaceus" is a lookalike spine fungus. It can be distinguished by its more compact fruit body structure that lacks multiple branches, in which the hanging spines all originate from a single thick tubercle. In "Hericium coralloides", the spines line the undersides of the branches, unlike "H. abietis", whose spines are arranged in clusters at the tip of branches.
Edibility.
"Hericium abietis" is edible and choice. David Arora suggests that cooking the mushroom produces a flavor similar to fish, and that it is suitable for sauteing, marinating, or preparing as a curry dish.
Habitat and distribution.
"Hericium abietis" causes a white pocket rot of conifers; this is a form of wood decay featuring a selective attack on lignin and hemicellulose in wood. The fruit bodies grow singly or occasionally in small groups on the dead wood of conifers, especially fir and Douglas fir. It can also be cultivated on conifer sawdust. The species is found throughout North America.