Phaeocollybia olivacea

The cap of Phaeocollybia olivacea starts out dark green, before becoming brownish, orangish, or reddish olive green. It is slimy when wet. It is about 3.5-10 centimeters in diameter. It starts out conical, before sometimes becoming convex with an umbo.^[1] The gills start out pale yellowish, before becoming olive or dull golden colored.^[2] The stipe can be up to 22 centimeters long, but most of it is hidden underground, with only 7-14 centimeters visible aboveground. The stipe is between 8 millimeters and 2 centimeters wide, and tapers underground.^[1] The spore print is brownish.^[2]

Phaeocollybia olivacea is found in mixed^[3] and coniferous^[2] forests, where it grows in clusters.^[3] It is mycorrhizal,^[2] and sometimes grows in fairy rings.^[4]