Silky Pinkgill Identification Guide

Where you are standing when you find it

Silky Pinkgill is a grassland species, and the habitat is usually the first clue rather than the mushroom itself. Picture closely grazed pasture, an old churchyard, a lawn that has never seen fertiliser, a mossy dune slack, or the trampled strip beside a coastal footpath. It comes up among waxcaps, earthtongues and fairy clubs, the classic community of unimproved short turf, and it is normally scattered rather than tightly clustered. What catches the eye from standing height is a small, dark, slightly greasy-looking brown cap sitting low in the sward, often with a paler ring around the margin where the cap has begun to dry. Bend down and the diagnostic character appears immediately: in dry weather the surface has a distinct silvery, satiny shine, quite unlike the matt dullness of most little brown grassland mushrooms.

Reading the cap

The cap is small, typically two to five centimetres across, starting bluntly conical or bell-shaped and flattening with age while keeping a low central bump or a shallow central depression. Colour ranges from dark sepia to a deep umber or almost blackish-brown when wet. The critical property is that it is strongly hygroscopic in the sense mycologists call hygrophanous: it changes colour dramatically as it loses water. Wet caps are dark and translucent, with the lines of the gills showing through the flesh as fine radial striations that reach a third or half of the way in from the edge. As the cap dries, the change starts at the centre and spreads outwards, leaving a two-tone mushroom with a pale ochre-buff middle and a dark, still-striate rim. The dried zone is where the silky sheen lives, and it is best seen by tilting the cap against the light rather than looking straight down at it. The surface is smooth to finely radially fibrillose, never scaly, never with veil fragments on the edge.

Gills and the colour clock

Turn the cap over and read the gills as a clock rather than a fixed character. In young buttons they are pale grey, greyish-white or faintly brownish. As the spores mature they take on a salmon or dull rose-pink flush that deepens until the whole underside is unmistakably pink-brown. This transition is the single most useful thing about the genus in the field, and if you find only immature grey-gilled specimens it is worth returning a day or two later. Attachment is adnate to broadly emarginate, that is, the gills meet the stipe squarely or with a small notch, and they often run a short distance down it as a fine decurrent tooth. Spacing is moderately distant, the edges are even and concolorous, and short intermediate gills of two or three lengths are interleaved between the full-length ones.

Stipe, base and flesh

The stipe is three to six centimetres tall and a few millimetres thick, more or less equal, sometimes flattened or twisted, and slightly wider at the very base. Its ground colour matches the cap but paler, and over that ground there is a covering of fine silvery longitudinal fibrils that give the whole stalk a polished, striate look. It is fibrous and snaps rather than tears cleanly. At the very base there is usually a small tuft of white mycelium binding a plug of soil and grass roots, which is worth lifting carefully so that the base is not left behind. There is no ring, no cortina and no volva, which rules out several groups at once. Cut the mushroom lengthways and the flesh is thin, brownish under the cap surface and paler within, and it does not change colour on exposure. Crush a fragment between finger and thumb and the odour is strongly farinaceous, a sharp cucumber-and-rancid note that persists on the fingers.

Taking and reading a spore print

Because the genus is defined by spore colour, a print is not optional here. Slice the stipe off flush with the gills, set the cap gill-side down on white paper, cover it with a glass or an upturned pot to slow evaporation, and leave it several hours or overnight. Silky Pinkgill drops a print that is unmistakably pink: salmon, dull rose or pinkish-brown depending on thickness. Judge the colour on white paper and in daylight, since a thin print on grey card can look almost colourless. If you have a lens or a microscope, the spores themselves are the confirmation, being distinctly angular in outline with five or six corners and roughly as long as they are broad, unlike the smooth ellipsoids of almost every look-alike group.

Substrate and season

This is a soil fungus of grassland, not a wood-rotting species, and it appears to live as a decomposer of grassland litter and humus. It favours old, unimproved, mossy turf on a range of soils and is frequent on calcareous downland, coastal grassland, dunes, lawns and churchyard swards. Fruiting runs from early summer into late autumn, peaking after rain in the same weeks as the waxcap season. Finding it in deep woodland litter or on wood chip should make you rethink the identification.

Separating it from look-alikes on morphology alone

The first cut is spore colour. Any small brown grassland mushroom with a white print belongs elsewhere: Fairy Ring Champignon has a tough, pliant stipe that can be bent double, pale tan cap and widely spaced pale gills; Clitocybe and Lyophyllum species have paler, more decurrent gills and no pink stage. A rusty-brown print with a dull ochre, radially fibrous or scaly cap points to Inocybe, and those also usually smell of something spermatic rather than farinaceous. A chocolate-brown print with free gills and a ring means Agaricus, and a black print with mottled gill faces means Panaeolus.

Within the pinkgills, the separations are structural. Entoloma sericellum is small and white or cream, never dark brown. Entoloma clypeatum is much larger, fruits in spring and grows under hawthorn, blackthorn and other rose-family shrubs rather than in open turf. Entoloma conferendum shares the grassland habit but has a more silky-fibrillose, paler and often umbonate cap and, decisively, cross-shaped spores. Entoloma papillatum and its relatives have a distinct nipple on the cap and a more hygrophanous, less shining surface. If you have a dark umber, strongly hygrophanous, silkily shining grassland cap with a farinaceous smell and a salmon print, Silky Pinkgill is the reading that fits every character at once.