Habitat/range: On hardwoods, causing a white rot of the sapwood. In BC, known from Quesnel and Vancouver Island. Elsewhere in western North America, known from WA, ID, MT, OR, and CA. Basidiomata reflexed or pileate, 2–10 cm wide × 3–15 cm long × 0.5–2.0 cm thick; pileus sessile, dimidiate, solitary, or imbricate; pileus surface buff, tomentose to glabrous, smooth; context buff, soft-fibrous, up to 1.5 cm thick; tubes pale smoky grey, up to 4 mm deep, separated from the context by a dark line; pore surface buff to pale smoky grey; pores round to angular,
2–5 per millimetre, edges thick, becoming thin, entire. Hyphae 3–7 μm diameter with clamp connections, walls thin to moderately
thick; basidiospores cylindrical to narrowly ellipsoid, 5–7 × 2.0–3.5 μm.
Notes: Basidiomata of B. adusta are more common and typically smaller, the context is thinner, the pores are smaller, and the dark line between the tubes and the context is less distinct.