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Red-brown Rocky Mountain porcini with a thick pale stem in spruce litter
Choice edibleintermediate

Rocky Mountain Porcini

Boletus rubriceps / Ruby porcini

A high-elevation spruce bolete with a red-brown cap, white then yellow pores, and pale netting on a thick stem.

Photo: Rachel, CC BY
Compiled by Mushroom Forage Map field deskExpert review pendingLast reviewed
Identification warning

Confirm pale stem reticulation, non-blue-staining pores, and local range. Avoid all red-pored or strongly blue-staining boletes as a beginner.

Season
Mid-summer through early fall after monsoon moisture
Habitat
High-elevation spruce and fir forest in the southern Rocky Mountains
Underside
White pores aging yellow to olive, without gills
Spore evidence
Olive brown

Observation season

When field records occur

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Compare before concluding

Lookalikes to rule out

King Bolete

harmless

The broad Boletus edulis concept overlaps in form, but geography, host, and DNA separate regional species.

Bitter Bolete

caution

Tylopilus felleus develops pinkish pores and dark netting and has intensely bitter flesh.

Red-pored Boletes

toxic

Red or orange pores and rapid blue staining move the specimen outside this porcini profile.

Identification

The cap is chestnut to deep red-brown and often looks polished when moist. Young pores are white and stuffed, then open and age yellow to olive. The thick club-shaped stem carries a fine pale net pattern, especially near the top. Cut flesh is white and should not rapidly turn blue.

Habitat narrows the identification: B. rubriceps is associated with high-elevation spruce and fir in the southern Rocky Mountains, including Utah, Colorado, New Mexico, and Arizona.

Uses and ecology

Firm, sound specimens are highly regarded cooked mushrooms and can be dried for concentrated flavor. Check for insect tunnels and soft pore layers, which develop quickly. A pore surface does not automatically mean edible; stem ornament, bruising, taste, and regional bolete knowledge all matter.

The fungus exchanges nutrients with living conifer roots and commonly fruits after sustained summer moisture.

Memorable fact

Rocky Mountain porcini was formally described as its own species in 2014 after long being folded into the European king bolete name.

Sources

Never eat a mushroom from this page alone

Reach 100% certainty using the whole specimen, multiple reputable sources, and a qualified local expert. Cook all wild mushrooms, try a small amount of one new species, and keep an uncooked specimen.

Safety and poison response
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