Ballen's American Caesar
Amanita calyptroderma · Family Amanitaceae · Updated October 2026
312US records
4states
Novbusiest month
312 US records since 1905 (275 in the last 10 years)
Last seen Dec 20, 2025 (about 10 months ago) in Stulsaft Park, CA, photographed by an iNaturalist user, with the ID agreed on by other iNaturalist users (research grade). Most US records come from California, Oregon and Washington, and the busiest months are Nov, Dec and Oct. (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.
☠ Dangerous genus. The genus Amanita includes death cap and destroying angels. Mushrooms in this group have caused serious or fatal poisonings.
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: Nov, Dec, Oct.
Where it's recorded
| State | Records | Latest sighting |
|---|---|---|
| California | 274 | Dec 20, 2025 |
| Oregon | 25 | Oct 12, 2025 |
| Washington | 11 | Oct 11, 1971 |
| Kansas | 2 | – |
Top counties
- Sonoma County, CA (55) · latest Nov 8, 2025
- Santa Cruz County, CA (54) · latest Nov 8, 2025
- San Mateo County, CA (35) · latest Dec 20, 2025
- Marin County, CA (28) · latest Dec 14, 2025
- Santa Clara County, CA (24) · latest Dec 3, 2025
- Contra Costa County, CA (15) · latest Nov 6, 2025
- Mendocino County, CA (12) · latest Nov 14, 2025
- Alameda County, CA (11) · latest Nov 23, 2025
- Benton County, OR (8) · latest Nov 3, 2023
- Nevada County, CA (7) · latest Nov 3, 2025
More on this species from GBIF.
Bring along
🍄
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.