Hygrocybe psittacina                        Parrot Mushroom

There are a couple of species of green mushrooms in Ontario.  If it's DRY and green check the pink-spored Leptonia incana (CLICK HERE)

Description

Caps are 1-4 cm across, slippery to slimy when wet, smooth, conic to bell-shaped or convex, with striate margin, olive-green to pea-green, and fading to yellow or ochre. Gills are attached, broad, well separated, green to orange or yellow. Stalks are up to 7 cm tall, slender, smooth, viscid to moist, green to yellow. Spore prints are white.  Widespread but not common, it fruits on the ground in woods.