Species details

Bitter beech bolete

Caloboletus calopus

Inedible
Bitter beech bolete – Caloboletus calopus

Photo: Tomasz Sobczak · CC BY-SA 4.0 · Photo source · License

Description

A colourful bolete with a pale cap, yellow pores and a yellow-red reticulate stem.

Identification features

The flesh often blues when cut; strong bitterness makes the species inedible.

Identification checklist

Check the entire fruitbody for identification. A colourful bolete with a pale cap, yellow pores and a yellow-red reticulate stem. The flesh often blues when cut; strong bitterness makes the species inedible. Typical habitat: Mainly deciduous and mixed woodland on base-rich soils, often with beech.

Detailed features

Cap
5–15 cm, hemispherical to convex, greyish to brownish, dry and smooth.
Hymenophore
Yellow tubes and small yellow pores that bruise blue-green.
Stem
5–15 × 4–6 cm, stout, yellow above and with a red reticulum over a yellow ground below.
Flesh
White to slightly yellowish, turning blue-green when cut.
Smell
Slightly sour.
Taste
Strongly bitter; tasting wild mushrooms is not a recommended identification method.
Spore print
Olive-brown.

Size

Cap diameter
5–15 cm
Stem height
5–15 cm
Stem diameter
4–6 cm

Habitat

Mainly deciduous and mixed woodland on base-rich soils, often with beech.

Fruiting period

June, July, August, September, October

Ecology

Trophic mode
Mycorrhizal
Host trees
Beech (Fagus)
Substrate
Forest soil
Soil
Calcareous
Notes
Mycorrhizal mainly with broadleaved trees; often in beech and mixed woodland.

How to separate similar species

Compare especially with these similar species: Rubroboletus satanas, Suillellus luridus, Rubroboletus rhodoxanthus. 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

Interesting facts

Did you know? The combination of yellow pores, a red-reticulate stem, blue staining and strong bitterness is highly characteristic.

Extended-description sources