Bitter Beech Bolete
Caloboletus calopus · Family Boletaceae · Updated October 2026
82US records
9states
Sepbusiest month
82 US records since 1901 (1 in the last 10 years)
Last seen Sep 29, 2022 (about 4 years ago) in Washington County, MO, a preserved specimen in Field Museum of Natural History (Botany) Fungi Collection. Most US records come from California, Washington and Idaho, and the busiest months are Sep, Oct and Aug. (Data as of October 26, 2026; records can lag by weeks.)
⚠ Never eat a wild mushroom based on this site. We show where fungi have been recorded, nothing more. We never say any mushroom is edible or safe, and you shouldn't decide that from any website, app or photo. Many deadly mushrooms look like harmless ones. If someone may have eaten a wild mushroom, call Poison Control at 1-800-222-1222 right away.
Lookalike warning. Many mushrooms, including deadly ones, closely resemble each other, and the only reliable identification comes from an expert looking at the actual specimen (often with spore prints or microscopy). Never use a name, photo or record count on this page to decide what something is.
When it's recorded
Records by month, all years. Busiest: Sep, Oct, Aug.
Where it's recorded
Top counties
- Sierra County, CA (19) · latest Oct 6, 1989
- Valley County, ID (6) · latest Aug 31, 1964
- Siskiyou County, CA (5) · latest Oct 2, 1983
- Tuolumne County, CA (4) · latest Sep 14, 1967
- Pierce County, WA (4) · latest 1971-09
- Fresno County, CA (3) · latest Sep 28, 1975
- Nevada County, CA (3) · latest Sep 14, 1965
- El Dorado County, CA (3) · latest Sep 10, 1983
- Amador County, CA (3) · latest Jun 25, 1985
- Madera County, CA (3) · latest Sep 10, 1967
More on this species from GBIF.
Bring along
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Regional mushroom field guideSee on Amazon🍄
Folding mushroom knife with brushSee on Amazon🍄
Wicker foraging basketSee on Amazon🍄
10x hand lens / loupeSee on Amazon🍄
Spore print paperSee on AmazonAs an Amazon Associate we earn from qualifying purchases.