Hexagonal-pored polyporus - Polyporus alveolaris

The fruit bodies of P. alveolaris are 1–10 cm (0.4–3.9 in) in diameter, rounded to kidney- or fan-shaped. Fruit bodies sometimes have stems, but they are also found attached directly to the growing surface. The cap surface is dry, covered with silk-like fibrils, and is an orange-yellow or reddish-orange color, which weathers to cream to white. The context is thin (2 mm), tough, and white. Tubes are radially elongates, with the pore walls breaking down in age. The pores are large—compared to other species in this genus—typically 0.5–3 mm wide, angular (diamond-shaped) or hexagonal; the pore surface is a white to buff color. The stipe, if present, is 0.5–2 cm long by 1.5–5 mm thick, placed either laterally or centrally, and has a white to tan color. The pores extend decurrently on the stipe. The spore deposit is white.
Wikipedia: