Agaricus bisporus, commonly known as the Portobello, Button or Crimini mushroom, is the most widely cultivated mushroom in the world. The mushroom grows naturally in grasslands, fields and meadows in North America and Europe.
- Cap: 3-16 cm, convex to broadly convex or nearly flat in age; dry; smooth or with pressed-down fibers or small scales; white in some varieties, brown in others.
- Spore print: brown
- Spores: 5.5-8.5 x 4-6.5 µ; elliptical; smooth. Basidia 2-spored.
- Bruising: brownish
- Gills: free from the stem; close; pinkish to pinkish brown at first, becoming dark brown to blackish.
- Stipe: 2-8 cm long; 1-3 cm. thick; sturdy; more or less equal; smooth or with small scales below the ring; white, often bruising brownish; with a ring that sometimes disappears in maturity.
- Veil: absent
- Mycelium: whitish, longitudinally radical, soon becoming cottony, and in age forming a thick, tenacious mycelial mat. Aged mycelium often secretes yellowish to orangish droplets of a metabolite which is a toxin to nematodes.)
Agaricus bisporus is the most widely cultivated edible mushroom in the world.
The bottom line is that I do not ingest products made from Agaricus fruitbodies unless they have been heated over 415˚ F, such as when mushrooms are broiled on a pizza. If the Agaricus industry would conduct a clinical study of their member farms and their employees, and compare their cancer rates relative to baseline populations, the looming questions as to whether Agaricus ingestion has net negative or positive effects could be put to rest. I think this responsibility is incumbent upon the Agaricus industry to finance and spearhead this study using unbiased, third party medical epidemiologists.
Bisporus is a coprophilic fungus (a dung-loving species) that often colonizes the dung of large herbivores, most notably cows and other grazing mammals such as goats. The mushroom grows naturally in grasslands, fields and meadows in North America and Europe. You can find it in late June through early fall