Fairy Ring Champignon

Description

The fairy ring champignon is a small mushroom with a cap 1-4 cm across, leathery yellow to ochre-brown, with a blunt umbo in the centre, which fades when it dries. The gills are distant and pale, and the stem is thin, solid, springy and not brittle. It tolerates drought well and revives when moistened.

It grows in meadows, lawns, pastures, along paths and at forest edges, from May to November, often in rings known as fairy rings. It is very common in Poland and is not protected.

It can be confused with poisonous funnel caps (especially the ivory funnel), which grow in the same meadows but have dense, decurrent gills and a less elastic stem, and with other small mushrooms. Other mushrooms also grow in fairy rings, so a ring alone proves nothing. If you are not sure of the species, do not pick or eat it.

Identification features

Cap

Diameter 1-4 (up to 6) cm; conical or bell-shaped when young, later convex, finally flat, usually with a blunt umbo in the centre. Colour leathery yellow, ochre-brownish or reddish-brown, hygrophanous (clearly paler, whitish when dry); cuticle dry, smooth, bare; margin sometimes faintly striate from the gills showing through.

Hymenophore (underside of the cap)

Gills very distant, whitish to light brownish (ochre after rain, cream in drought), thick, adnate to the stem or free.

Stem

Height 2-7 cm, thickness 2-6 mm, cylindrical, solid, elastic, not brittle, pliant-fibrous, pale ochre to whitish-yellowish, bare. No ring and no volva.

Flesh

Thin, white to pale yellow, does not change colour when cut. Smell mushroomy, pleasant; some descriptions give a smell resembling hydrogen cyanide (almonds); taste mild. Do not taste the flesh of unidentified mushrooms.

Spore print and spores

Spore print white. Spores ovoid to ellipsoid, smooth, colourless, non-amyloid, 7-10 × 4-6 µm.

Habitat and distribution

Ecology. Saprotroph. Grows in meadows, pastures, lawns, along field paths, at forest edges and on coastal dunes. Forms fairy rings that may be up to 20 cm wide or more; the mycelium at the edge of the ring stimulates grass growth (a dark green band), while inside the ring the dried-out mycelium inhibits growth (it releases ammonia, and the grass dies). Excess nitrogen from artificial fertilisers does not favour the species; it grows mainly on soils of low and medium fertility.

Distribution. Temperate zone of the whole Northern Hemisphere and Australia; very common in Central Europe, including Poland. Not legally protected in Poland.

Fruiting. From May to November; in a warmer climate throughout the year.

What can it be confused with?

• Clitocybe dealbata (ivory funnel) and Clitocybe rivulosa — Poisonous; they have densely spaced, decurrent gills, a less elastic stem, a frosted cap (without an umbo in C. rivulosa, whitish-grey) and a different smell. They grow in the same places.
• Gymnopus peronatus (wood woollythigh) — Mentioned as a similar species; detailed differences - no data.
• Some Mycena, Collybia, Marasmiellus, Micromphale, Strobilurus; Marasmius nigrodiscus — Mentioned as similar; distinguishing them is sometimes possible only under a microscope; details - no data.

Never rely on a single feature. If you are not sure — do not pick it; show the mushroom to a qualified mushroom expert.

Interesting facts

• The fairy rings formed by this mushroom are usually up to 20 cm across; the band of dark green grass is an effect of the mycelium, and inside the ring the grass dies.
• Its ability to revive after complete drying is explained by the presence of trehalose, a sugar that protects cells from desiccation; it is also a possible source of the sweet taste.
• The Polish name was given by Franciszek Błoński in 1889.
• David Arora considers it one of the few "little brown mushrooms" worth getting to know.