Cultivated Mushroom
Agaricus bisporus · Family Agaricaceae · Updated October 2026
403US records
15states
Marbusiest month
403 US records since 1916 (43 in the last 10 years)
Last seen Apr 15, 2026 (about 6 months ago) near Lawrence, Douglas County, KS, a preserved specimen in R. L. McGregor Herbarium Lichen Collection. Most US records come from California, Maryland and New Mexico, and the busiest months are Mar, Apr and Feb. (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: Mar, Apr, Feb.
Where it's recorded
Top counties
- Riverside County, CA (154) · latest 1992-04
- Monterey County, CA (45) · latest Mar 23, 2009
- San Francisco County, CA (40) · latest Mar 28, 1991
- Prince George's County, MD (40) · latest Apr 11, 2019
- San Mateo County, CA (30) · latest Apr 24, 1991
- Santa Cruz County, CA (13) · latest Apr 7, 2012
- Anne Arundel County, MD (9) · latest Apr 11, 2019
- Colfax County, NM (8) · latest Jul 29, 2004
- Ontario County, NY (7) · latest Mar 13, 1934
- Clinton County, PA (5) · latest 1993-04
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.