Conifercone Cap Identification Guide

Standing in the Right Place

Almost every find of the Conifercone Cap happens in the least photogenic part of a wood: the dim, needle-carpeted interior of a spruce or pine stand, where nothing much grows at ground level and the litter is a springy brown mat rather than leaf mould. There is no showy troop to catch your eye from the path. Instead you notice, at ankle height, a scatter of very small pale-brown mushrooms standing in ones and twos with unusually long, thin stems for their size, apparently rooted in bare needles.

The moment you see that picture, change your posture. Kneel, part the needle litter with your fingers around the base of one fruit body, and follow the stem down. If the stem leads to a fallen conifer cone - often half-buried, blackened and softened - you have arrived. The Conifercone Cap is one of a small guild of fungi that live on nothing but cones, and the substrate is a large part of the identification. A mushroom of this shape and size sitting on plain soil or on a log is something else entirely.

Find the Cone First, Then the Mushroom

Work the excavation slowly. Cones sink into needle duff quickly and may sit two or three centimetres down, so a fruit body that looks terrestrial usually is not. Use a knife or a stick to lift the whole cone out with the mushrooms still attached, rather than snapping the stems. What you want to see is the stem base running directly into the gap between two cone scales, often with fine white cords of mycelium spreading across the cone surface and out into the surrounding needles.

Spruce cones are the commonest host across much of Europe, pine cones in drier sandy woodland, and the fungus will also work on Douglas fir and larch cones. A single well-rotted cone can carry anywhere from one to twenty fruit bodies at different ages, which is convenient - you get young buttons and expanded mature caps in the same handful.

Reading the Cap

Take a mature cap and hold it against a neutral background. It is small: 5 to 20 millimetres across, occasionally reaching 25 on a rich cone. Shape runs from hemispherical or convex in youth to broadly convex or almost flat with age, usually with a shallow low umbo or simply an evenly rounded profile. The margin is thin, often slightly incurved when young, and in wet weather it becomes faintly translucent-striate so that the lines of the gills show through as fine radial shading.

Colour is the classic unhelpful brown of a hundred small fungi - but it behaves in a specific way. Fresh and moist, the cap is date-brown to warm cinnamon or reddish-tan, darkest over the centre. It is markedly hygrophanous, so as it dries it fades from the margin inwards to pale buff, ochre-cream or almost whitish, frequently leaving a two-tone cap with a darker disc and a pale rim. The surface itself is smooth, dry to slightly greasy, matt rather than shiny, and never scaly or granular.

The Gills That Name the Genus

Turn it over, and this is the step that settles the identification. The gills are extraordinarily crowded - far more so than any small brown mushroom of this size has any business being. On a cap under two centimetres wide you may be looking at eighty to a hundred and forty gills counted at the margin, packed so tightly that in dry weather they read almost as a fluted surface rather than as separate plates. Several tiers of short intermediate gills fill in between the full-length ones.

The gills themselves are narrow, thin, and attached to the stipe in a narrowly adnexed or almost free manner. Colour is white to pale cream at first, ageing to a faint pinkish-buff or dirty cream; they never develop rusty, brown or blackish tones. The edges stay even and concolorous. If you have crowded, narrow, pale gills over a cone, you are essentially there.

Stipe, Base and the White Fur

The stipe is 20 to 50 millimetres long and only 1 to 2 millimetres thick, cylindrical, slightly flexuous, hollow, and rather tough and pliant - it bends before it snaps, unlike the brittle stems of most small Mycena species. Colour is whitish or pale buff at the apex, shading to tan, ochre-brown or reddish-brown in the lower half.

Run a hand lens along it. The whole surface, and especially the lower part, is finely pruinose or minutely mealy with white hairs, and towards the base this thickens into a distinct coat of white downy or shaggy fur. The base tapers into a short pseudo-root that pushes between the cone scales, and that root is normally wrapped in visible white felt with fine white mycelial strands running off it. The specific epithet refers to this mouse-tail-like base. There is no ring, no cortina and no volva.

Flesh, Colour Change and Odour

The flesh is very thin, whitish to pale watery brown, and unremarkable - which is itself useful information. Cut a cap and a stipe lengthways and watch for a minute: there is no bruising reaction, no reddening, no blackening, no latex and no bluing. Odour is faint and mushroomy at most, with no chemical or nitrous note. A cone mushroom with a strong smell of bleach or of crushed leaves is pointing you elsewhere.

Taking a Spore Print

The caps are small, so lay several of them, gills down, on a piece of glass or a strip of black card, cover with an upturned cup to hold humidity, and leave for four to six hours or overnight. On black card the deposit shows clearly as white to very pale cream. That white print, combined with pale crowded gills, rules out every rust-brown, pink or blackish-spored possibility in a single step.

If you have a microscope, the genus name gives away the confirming character: the spores are tiny, ellipsoid to almost cylindrical, roughly 3 to 4.5 by 1.5 to 2 micrometres, and they turn blue-grey in Melzer's iodine reagent. Amyloid, minute spores plus crowded gills plus a cone is a complete identification.

Substrate and Season

The fungus is a litter and cone decomposer, breaking down the tough lignified scales and central axis of fallen conifer cones and, occasionally, drifts of needle debris and twiggy fragments. It fruits mainly from early autumn to the first hard frosts, and in oceanic climates with few hard frosts it carries on through December and January - it is one of the few things worth kneeling for in a plantation in midwinter. Look on the ground under mature spruce, in old pine shelterbelts, in Douglas fir plantations, and along forestry rides where cones accumulate in drifts.

Separating It from the Other Cone Dwellers

The critical comparison is with the genus Strobilurus, which occupies exactly the same cones. Strobilurus tenacellus on pine cones and Strobilurus esculentus on spruce cones both have caps of similar size and brownish colour, but the gills give them away: they are moderately close at best, distinctly broader, and countable at a glance rather than a blur. Their stipes differ too - typically smooth or only finely velvety in the upper part, coloured yellowish to ochre-brown or reddish-brown, and drawn out into a long, tough, cartilaginous taproot rather than a short root inside a white felted collar. Strobilurus species also mostly fruit from late winter into spring, whereas Baeospora myosura peaks in autumn and early winter, so overlap is possible but not the norm.

Mycena strobilicola is another spruce-cone species, appearing in early spring; it has a conical grey-brown cap, far fewer gills and a strong nitrous smell. Auriscalpium vulgare shares pine cones but bears spines instead of gills and has a hairy, laterally attached stem. Baeospora myriadophylla has the same ridiculous gill count but grows on rotten hardwood logs and shows lilac tones in the young gills. Ordinary small Mycena and Gymnopus species that wander through needle litter will have broader, fewer gills, brittle stems, and no cone at the base once you dig.

A Field Sequence That Works

Dig to find the cone; count gills and confirm they are too many to count comfortably; check the pale, unchanging gill colour; run a lens down the stipe looking for white pruina and a furry rooting base; take a print on dark card and confirm it is white. Five steps, five minutes, and a genuinely secure identification of one of the smallest specialists in the conifer wood.