Porcini vs Bitter bolete: how to tell them apart

Bitter boletes are not poisonous, but a single one ruins a dish with its bitterness. Look for pink-tinged pores on older bitter boletes and a coarse, dark net all over the stem. Porcini have white to olive-yellow pores and a fine, pale net on the upper stem only.

Side-by-side comparison

	Porcini Boletus edulis	Bitter bolete Tylopilus felleus
Safety status	Edible (expert ID)	Inedible
Cap	Brown to chestnut, 7–25 cm, smooth, slightly sticky when wet	Tan to brown, 5–15 cm, dry and velvety
Underside	Sponge-like pores: white when young, yellowish-olive when mature, never red	Pores white when young, turning dirty pink with age
Stem	Swollen and barrel-shaped, white to pale brown with a fine white net pattern near the top	Brown with a coarse, dark brown net over the whole stem
Smell	Pleasant, nutty	Mild
Spore print	Olive-brown	Pinkish-brown
Habitat	Spruce, pine, beech, oak and birch woods	Acid soils under conifers, sometimes beech and oak
Season	Jun – Nov	Jul – Oct

Photos: ReddishClover, CC BY-SA 4.0 · bernd gliwa, CC BY-SA 2.5

Quick tests that separate them

1. Pores: dirty pink in age (bitter bolete) vs white then olive-yellow (porcini).
2. Stem net: dark and coarse (bitter bolete) vs fine and white at the top (porcini).
3. Cap texture: velvety dry (bitter bolete) vs smooth and slightly sticky (porcini).
4. Tasting wild mushrooms to identify them is not recommended.

Key clues for each

Porcini: White net pattern on the upper stem, pores that never stain red and never turn blue when cut, and a mild nutty smell.

Bitter bolete: Pink pores in older specimens and a dark, coarse net on the stem (porcini have pale pores and a fine white net).

Frequently asked questions