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White horse mushrooms with dark gills in grass
Edibleexpert-only

Horse Mushroom

Agaricus arvensis

A large white grassland Agaricus with an aniseed smell, a cogwheel ring, and gills maturing to chocolate brown.

Photo: Lucian Clanet, CC BY
Compiled by Mushroom Forage Map field deskExpert review pendingContent checked
Identification warning

Destroying angels are white with white gills and a volva. The yellow stainer bruises chrome yellow and smells of ink.

Season
Summer to autumn
Habitat
Pastures, meadows, and grassy verges
Underside
Free gills, pale gray-pink maturing to chocolate brown
Spore evidence
Dark brown

Where it grows

Tracked records and known growing zone

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Squares: where people recorded it, brighter where more people did
Verified records
585
People who recorded it
487
Most records (northern hemisphere)
Jun, Aug–Oct
Records span
1986–2026

Research-grade iNaturalist records, snapshot Aug 27, 2026. The growing zone combines areas where different people have repeatedly verified it. Records show where people looked and found it, not current abundance or permission to gather.

Observation season

When field records occur

Choose a hemisphere · All recorded years; not a current forecast.

Choose the hemisphere you want to study. Country detection is approximate and some countries span the equator.

Compare before concluding

Lookalikes to rule out

Yellow stainer flashes chrome yellow at the cut stem base and smells of ink or phenol.

Meadow mushroom is smaller with bright pink young gills and a thin ring.

Identification

The cap is white to cream, slowly yellowing when handled, and smells of aniseed or almond. Gills are free, pale grayish pink when young and chocolate brown with age, never pure white at maturity. The large ring has a cogwheel pattern underneath. There is no volva at the base.

Uses and ecology

Horse mushrooms are grassland decomposers, often in rings. They are a traditional edible in Europe. Like other Agaricus, they can concentrate cadmium from polluted soils, so avoid roadsides.

Memorable fact

Its yellow staining is slow and gentle, unlike the instant chrome yellow of the yellow stainer.

Sources

Never eat a mushroom from this page alone

Confirm identity using the whole specimen, multiple reputable sources, and a qualified local expert. Identified edible species still require appropriate preparation. Cooking does not make a poisonous mushroom safe.

Safety and poison response
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