The buttery collybia is a brown mushroom that grows in scattered groups in forest litter across North America, especially in pine needle beds, where it helps break down fallen conifer debris. Its name comes from the cap, which feels slick and greasy when wet. It is also called the butter cap.
Appearance
- Appearance
- The cap is about 1–4 in (2–10 cm) across, rounded at first and later nearly flat. It is reddish brown to brown when moist and fades to cinnamon or pale buff as it dries, often unevenly, so the cap can look zoned.
- Growth form
- Gills are whitish and crowded, often with finely jagged edges. The stem is usually club-shaped, becomes hollow, and has white fuzz at the base. Spore print is whitish to faintly pinkish cream.
Look-alikes
Gymnopus dryophilus usually has a more yellow-brown cap that is moist rather than slick, a straight stem, and smooth gill edges; in California it is more often found under oaks. Butter cap tends to be redder, with a club-shaped stem and finely jagged gills. The surest test is microscopic (spore staining reaction).
Why they get mixed upBoth are small brown-capped mushrooms that grow in groups in forest litter.
Where it lives
- Typical habitats
- Pine woods
- Conifer forests
- Mixed woods
- Range
- Widely distributed in North America; in California it grows in both coastal and mountain areas. It is also common in Europe and Japan.
- Preferred conditions
- Grows on fallen needles and leaf litter rather than on living trees, especially under pines and occasionally under hardwoods. In most of the US it fruits in late summer and fall; in California and other mild areas it appears from late fall into midwinter.
- Seasons
In California
Fruit Nov–Jan
Life cycle
- Reproduction
- Like other gilled mushrooms, it releases spores from its gills; the fruiting bodies are only the visible part of a network of threads living in the litter.
Cautions
- Cautions
- Some references list it as probably edible, but it is thin-fleshed and has little culinary record. It resembles other brown litter mushrooms, so field guides advise caution.
Name and classification
- About the name
- First described in 1792 as Agaricus butyraceus and long known as Collybia butyracea, a name many older field guides still use. It was moved to Rhodocollybia in 1979. DNA work has found at least two distinct groups under this name, so more than one species may be involved.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
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