Community find

Jack O'Lantern Mushroom

Omphalotus illudens

Group

Gilled mushroom

Season

Late summer to fall.

Habitat

Typically grows in large, dense clusters on decaying wood of hardwoods, especially oak. Can sometimes appear to be growing from the ground, but this is usually from buried wood.

Key characteristics

Cap: 5-20 cm wide, convex becoming flat or depressed, often with a central umbo; orange to orange-yellow to brownish-orange. Gills: Deeply decurrent, numerous, narrow, orange, bioluminescent. Stem: 5-20 cm long, 1-3 cm thick, tapered towards the base, same color as the cap, solid, often eccentric. Spore Print: Pale yellow to white. Flesh: Orange-yellow.

Look-alikes

Chanterelles (Cantharellus spp.): Chanterelles have false gills (folds in the cap tissue) that are blunt, shallow, and usually run down the stem less distinctly than the true gills of the Jack O'Lantern mushroom. Chanterelles also typically grow scattered or in small groups on the ground, not in large clusters on wood. Additionally, Chanterelles are not bioluminescent. Saffron Milkcap (Lactarius deliciosus): Has distinct gills, but exudes an orange 'milk' when cut or broken, which Omphalotus illudens does not. Also grows mycorrhizally with conifers.

Ecological role

Saprotrophic, playing a role in the decomposition of dead hardwood, returning nutrients to the ecosystem.