Agaricus arvensis

Agaricus arvensis

Agaricus arvensis in its natural habitat

Agaricus arvensis showing the cogwheel pattern

Agaricus arvensis, commonly known as the horse mushroom, is a species of fungus in the Agaricaceae family. It is widely distributed in temperate regions and is often found in grassy areas such as meadows, pastures, and lawns.

Description

The cap of Agaricus arvensis is typically 5 to 15 cm in diameter, initially convex, becoming flat with age. The surface is smooth and white, sometimes with a slight yellowish tint. The gills are free from the stipe and are initially pink, turning chocolate brown as the spores mature.

The stipe is 5 to 10 cm tall and 1 to 2 cm thick, with a distinctive double annulus or "cogwheel" pattern, which is a key identifying feature. The flesh is white and may turn slightly yellow when bruised.

Habitat and Distribution

Agaricus arvensis is commonly found in Europe, North America, and other temperate regions. It grows in grasslands, often in fairy rings, and is associated with nutrient-rich soils.

Edibility

The horse mushroom is considered a choice edible mushroom, with a pleasant anise-like odor. However, it can be confused with toxic species such as Agaricus xanthodermus, which has a similar appearance but a distinctive phenolic odor and yellow staining reaction.

Related Species

Agaricus arvensis is closely related to other species in the Agaricus genus, including:

• Agaricus campestris - the field mushroom
• Agaricus bisporus - the common mushroom
• Agaricus xanthodermus - the yellow-staining mushroom

Related Pages

• Fungus
• Mushroom
• Mycology
• Edible mushrooms

Gallery

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  Agaricus arvensis in its natural habitat
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  Agaricus arvensis showing the cogwheel pattern

Agaricus arvensis

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  Agaricus arvensis in the field
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  Agaricus arvensis showing cogwheel