Dang BFE I really hope you did not get the wrong kind because
that genus’ identification is easily mistaken. I believe that the source
of your mushroom is safe and reliable. The portabella DOES have
a ring on the stipe.
Agacarius Bisporus (quote from Wiki)
The pileus or cap of the original wild species is a pale grey-brown in color, with broad, flat scales on a paler background and fading toward the margins. It is first hemispherical in shape before flattening out with maturity, and 5–10 cm (2–4 in) in diameter. The narrow, crowded gills are free and initially pink, then red-brown and finally a dark brown with a whitish edge from the cheilocystidia. The cylindrical stipe is up to 6 cm (2⅓ in) tall by 1–2 cm wide and bears a thick and narrow ring, which may be streaked on the upperside. The firm flesh is white though stains a pale pinkish-red on bruising. The spore print is dark brown. The spores are oval to round and measure around 4.5–5.5 x 5–7.5 μm, and the basidia usually two-spored, although two tetrasporic varieties have been described from the Mojave desert and the Mediterranean with predominantly heterothallic and homothallic lifestyles, respectively
Commonly found in fields and grassy areas after rain from late spring through to autumn worldwide, especially in association with manure. It is widely collected and eaten, even by those who would not normally experiment with mushrooming.
raw Nutritional value per 100 g (3.5 oz)
Energy 94 kJ (22 kcal)
Carbohydrates 3.28 g
- Sugars 1.65 g
- Dietary fiber 1.0 g
Fat 0.34 g
Protein 3.09 g
Water 92.43 g
Thiamine (Vit. B1) 0.081 mg (6%)
Riboflavin (Vit. B2) 0.402 mg (27%)
Niacin (Vit. B3) 3.607 mg (24%)
Pantothenic acid (B5) 1.497 mg (30%)
Vitamin C 2.1 mg (4%)
Iron 0.50 mg (4%)
Percentages are relative to US recommendations for adults.
Source: USDA Nutrient database
Similar speciesSee also: Mushroom hunting
The common mushroom could be confused with young specimens of the deadly poisonous destroying angel (Amanita sp.), but the latter can be distinguished by their volva or cup at the base of the mushroom and pure white gills (as opposed to pinkish or brown of Agaricus bisporus). Thus it is important to always clear away debris and examine the base of a mushroom, as well as cutting open young specimens to check the gills. Furthermore, the destroying angel grows in mossy woods and lives symbiotically with spruce.
A more common and less dangerous mistake is to confuse Agaricus bisporus with Agaricus xanthodermus, an inedible mushroom found worldwide in grassy areas. Agaricus xanthodermus has an odor reminiscent of phenol; its flesh turns yellow when bruised. This fungus causes nausea and vomiting in some people.
The poisonous European species Entoloma sinuatum has a passing resemblance but has yellowish gills turning pink and lacks a ring.