Species details

Bronze bolete

Boletus aereus

Extra caution required
Bronze bolete – Boletus aereus

Photo: Sarah Faulwetter · CC BY 4.0 · Photo source · License

Description

A stout bolete with a very dark brown cap, white to olive pores, and a distinct net on the stem.

Identification features

The flesh is white and normally does not blue; the cap is dry to velvety and the stem is often bulbous.

Identification checklist

Check the entire fruitbody for identification. A stout bolete with a very dark brown cap, white to olive pores, and a distinct net on the stem. The flesh is white and normally does not blue; the cap is dry to velvety and the stem is often bulbous. Typical habitat: Warm deciduous woodland, especially with oak, beech, and sweet chestnut.

Detailed features

Cap
6–20 cm, hemispherical to cushion-shaped, very dark brown to almost black-bronze, dry and velvety; not slimy.
Hymenophore
Tubes and pores start white, then become yellow and olive-green.
Stem
7–15 × 3–6 cm, initially bulbous, later cylindrical, firm, with fine reticulation.
Flesh
White and firm, normally not blueing.
Smell
Mild and pleasant.
Spore print
Brown-olive.

Size

Cap diameter
6–20 cm
Stem height
7–15 cm
Stem diameter
3–6 cm

Habitat

Warm deciduous woodland, especially with oak, beech, and sweet chestnut.

Fruiting period

June, July, August, September, October

Ecology

Trophic mode
Mycorrhizal
Host trees
Oak (Quercus), Sweet chestnut (Castanea)
Substrate
Forest soil
Notes
A warmth-loving mycorrhizal species of deciduous woodland, especially with oak and sweet chestnut.

How to separate similar species

Compare especially with these similar species: Boletus edulis, Boletus reticulatus, Tylopilus felleus. Check the combination of cap shape and colour, spore-bearing surface, stem, flesh changes and habitat. A single feature or photograph is not enough; if the key characters do not match the description, do not treat the identification as confirmed.

Similar species

Extended-description sources