Bitter Bolete

Tylopilus felleus

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The Bitter Bolete is a type of mushroom belonging to the Boletaceae family. Distinguished by its brown cap and white pores which slowly turn pinkish with age, it’s primarily known for its strong bitter taste which renders it inedible for most.

Bitter Bolete

Common Name
Bitter Bolete

Latin Name

Tylopilus felleus


Found across North America, Europe, and Asia in both coniferous and broadleaf forests.


It possesses a brown or tan cap, with white pores underneath that become pinkish as the mushroom ages. The stem is thick and may feature a network-like pattern.


The cap can be between 8 to 20 cm (about 3 to 8 inches) across, and the stem can be 6 to 12 cm (about 2.5 to 5 inches) in height.


Prefers hardwood forests but can occasionally be found under conifers.


Mycorrhizal, forming a symbiotic relationship with the roots of living trees, particularly with oaks and other hardwoods.


Like most fungi, the Bitter Bolete begins as spores which, once germinated, form mycelial threads. These threads interweave and, under the right conditions, produce the fruiting body known as the mushroom. This mushroom then releases spores to propagate the species.

Defense Mechanisms

Its defining bitter taste serves as a natural deterrent against consumption.

Ecological Importance

As a mycorrhizal fungus, it aids in nutrient exchange with trees, promoting forest health and sustainability.

Conservation Status

Not listed as threatened; it’s a common species in many regions where it is native.
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