About Rhodocollybia butyracea (Bull.) Lennox
The cap of Rhodocollybia butyracea measures 2 to 10 centimetres (3⁄4 to 4 inches) across. It starts convex, and matures into a broadly convex or nearly flat shape. When fresh, the cap is smooth and moist, with a reddish-brown colour that fades to cinnamon. The gills are either free from the stem, or narrowly attached to it. Gill spacing ranges from close to crowded, and the gills are whitish in colour. Occasionally, gills develop a pinkish tone as they age, and they often have fine, jagged edges. The stem grows up to 10 cm long and 1 cm thick, and is normally somewhat club-shaped. It can be either moist or dry. The flesh of this mushroom is white, with no distinctive odor or taste. Spores are pale yellowish, pale pinkish, or white. Rhodocollybia butyracea is widely distributed across North America. It is a saprobic species that decomposes conifer litter, most commonly litter from the genus Pinus, and occasionally decomposes litter from hardwoods.
