Assessment Notes

Justification

Agaricus campestris is a globally widespread edible saprobic fungus and there is no evidence of significant decline. It can be locally abundant where suitable habitat exists. Therefore, it is assessed as Least Concern (LC).

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Taxonomic notes

Note that Agaricus campestris var. floccipes (F.H. Møller) Pilát, is treated as a synonym of Agaricus moellerianus Bon (Index Fungorum 2019).

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Geographic range

Field Mushrooms have a truly world-wide distribution. They occur throughout most of Europe, Asia, North America, Australia and New Zealand (e.g. see Boa 2004). The area of occupancy (AOO) of this species is much larger than 2,000 km², and its extent of occurrence (EOO) is much larger than 20,000 km².

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Population and Trends

The population size is likely to be very large since this is such a widespread species in a more or less stable habitat. There are a few reports claiming that the species locally may be in be in decline related to the decline in horse populations in rural areas.

Population Trend: Stable

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Habitat and Ecology

Agaricus campestris is a decomposer fungus, widespread in pastures and other grasslands after rain from late summer onwards, worldwide. It is also found on lawns in suburban areas. It appears in small groups, in fairy rings or solitarily.

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Threats

It is commonly and widely found in pastures and grassy areas. Some information suggests that it locally may be declining, related to the decline in pasture-animal populations (e.g. horses) in rural areas. However, it is not nationally red listed in any country.

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Conservation Actions

No conservation measures are needed for this species since it is widespread and there are no major threats to it.

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Use and Trade

Agaricus campestris is a commonly eaten wild mushroom. It is closely related to the cultivated button mushroom Agaricus bisporus, but not commercially cultivated on account of its fast maturing and short shelf-life.

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Source and Citation

Dahlberg, A. 2019. Agaricus campestris (errata version published in 2022). The IUCN Red List of Threatened Species 2019: e.T122090215A222966644. Accessed on 21 November 2025.

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• Country occurrence