Community find

Berkeley's Polypore

Bondarzewia berkeleyi

Group

Polypore

Season

Generally found from summer to early autumn, typically from July through September, depending on geographical location and moisture levels.

Habitat

Typically found growing at the base of living deciduous hardwood trees, especially oak, maple, and beech, causing a white heart rot. It can also be found on decaying stumps or buried roots. It prefers temperate forests.

Key characteristics

This mushroom typically forms large, overlapping shelf-like or rosette clusters, often at the base of hardwood trees. The caps are usually fan-shaped, grayish-white to yellowish, and can be zoned. The underside features a poroid surface that is white to cream-colored, with small, angular pores. The flesh is tough and fibrous, white, and does not change color when cut. Individual caps can range from 10-60 cm across, and the entire cluster can weigh many kilograms. It has no true stem, but rather a thick, rudimentary base.

Look-alikes

Similar species include the Black-staining Polypore (Meripilus sumstinei), which stains black when bruised or handled. Another look-alike is the Hen of the Woods (Grifola frondosa), which has a more intricate, cauliflower-like structure and thinner caps, and also typically stains light brown or not at all. The Berkeley's Polypore does not stain significantly upon bruising.

Ecological role

It is a parasitic white rot fungus, causing decay in the heartwood of living hardwood trees, primarily oaks. It eventually leads to weakening and hollowing of the host tree. It also acts as a decomposer, recycling nutrients back into the ecosystem once the tree dies.