Flammulina velutipes

Common Name: Winter Mushroom.
Description: Cap 1.5-6 cm broad, convex, nearly flat in age, viscid, reddish yellow, reddish orange to reddish brown, margin often irregular. Flesh thick, white to yellowish. Stalk 2-6 cm long, 3-8 mm thick.
Habitat: Single but most often in cespitose clusters on living trees in late fall, winter and spring. Widely distributed. Cold loving.
Edible: Yes, and tasty.

Source: Mushrooms of North America by Orson K. Miller, Jr.