Birch Mazegill Lenzites betulinus (L.) Fr. (illustrated 70% life size) Bracket 3–8cm×2–4cm across, 0.3–1.5cm thick, semicircular or fan-shaped, often in overlapping groups; upper surface uneven, concentrically grooved and zoned, whitish, grey, tan, and brown, covered in fine hairs in which algae may grow, giving the surface a green tinge; tough and leathery. Flesh white; cottony. Gills forked and fused together in places; straw-yellow to buff-grey. Spores 5–6×1.5–3¼, subcylindrical; white. Hyphal structure trimitic. Habitat on deciduous trees, also on cut timber; all year. Frequent. Not edible.