Community find

Bitter Bolete

Tylopilus felleus

Group

bolete (pored mushroom)

Spore print

Pink to vinaceous-brown.

Size

Cap diameter: 5-15 cm; Stipe length: 4-10 cm, width: 1-3 cm.

Season

Typically fruits from July through October (summer and autumn).

Habitat

Found in coniferous or deciduous forests, often associated with hemlock, pine, or oak; grows on the ground or occasionally on well-decayed logs and mossy stumps.

Distribution

Common throughout eastern North America and Europe; also reported in parts of Asia.

Key characteristics

Convex cap that becomes flatter with age, brown to tan in color with a smooth texture; distinct white pores that turn pinkish-buff or brownish when bruised or with age; a thick, brownish stipe often featuring prominent, dark brown raised reticulation (a net-like pattern).

Fruiting body

Cap: 5-15 cm wide, dry, smooth to slightly velvety, brown to tan; Hymenophore: Pores initially white, turning pinkish with maturity; Stipe: 4-10 cm long, 1-3 cm thick, solid, yellowish-brown with prominent dark brown reticulation above.

How to recognise it

The most diagnostic features are the pinkish mature pores and the dark, heavy reticulation on the stalk compared to the white/pale reticulation found on many Boletus species.

Look-alikes

Boletus edulis (King Bolete) which has white reticulation on the stipe and yellow-green pores; Tylopilus rubrobrunneus which has a more reddish-brown cap.

Ecological role

Mycorrhizal, forming symbiotic relationships with various tree species to facilitate nutrient exchange.

Notes

This species is famous among mycologists for its extreme bitterness, which is not neutralized by cooking; a single specimen can ruin the flavor of an entire dish if mixed with other mushrooms. It is a common 'look-alike' that serves as a diagnostic test for beginners identifying porcini.