beech agaric

Description

The gills are white and distant, and the curved, whitish stem bears a large, drooping ring. The flesh is thin, soft and without a distinct smell.

It grows in clusters on dead trunks, logs and branches of beech, in forests and parks, from June to November, often high above the ground. The wind can knock single fruiting bodies down from the tree crowns. In Poland it is not very common.

It is very distinctive: the white, slimy cap, the ring and the exclusive habitat on beech wood make it hard to confuse with anything else. Even so, do not collect or eat mushrooms you are not sure of.

Identification features

Cap

Diameter 2–10 cm; hemispherical or strongly convex in young specimens, then increasingly flat, finally spread out with a blunt umbo. Margin sharp, wrinkled-striate. Surface pure white or whitish, ivory-coloured, sometimes pale greyish when young, often ochre and semi-translucent at the centre. Very sticky, slimy and glutinous in wet weather, silky-matt and smooth in dry weather. The cap cuticle is of the hymeniform type (erect, club-shaped cells).

Hymenophore (underside of the cap)

Gills white, broad, bulging, very distant, adnate to sinuate, sometimes slightly decurrent.

Stem

Height 3–10 cm, thickness 3–10 mm, cylindrical, solid, tough, often curved. Surface smooth, sticky, whitish, striate above the ring, brownish or greyish and slightly scaly towards the base. A large, drooping or spreading, membranous ring. Fruiting bodies growing from the underside of a trunk have stems curved so that the caps are held horizontally, with the gills facing down.

Flesh

White; very thin and soft in the cap, fibrous and tough in the stem. Taste mild, no distinct smell. Does not change colour when damaged.

Spore print and spores

Spore print white. Spores subglobose to broadly ellipsoid, smooth, thick-walled, 13–18 × 12–16 µm (descriptions give slightly different ranges).

Habitat and distribution

Ecology. Saprotroph or weak parasite on wood, strongly tied to beech (Fagus); grows on logs, trunks and fallen branches of dead beech, also on dead branches high in the crowns of living trees. Recorded on oak very rarely. Produces strobilurins – fungicidal compounds that limit competing fungi on the colonised wood.

Distribution. Europe (northern and central, wherever beech grows) and East Asia (Japan, Korea, Taiwan). In Poland not very common; found in forests and parks. Not under species protection in Poland.

Fruiting. Fruiting bodies grow in clusters from June (according to some descriptions from late summer) to November.

What can it be confused with?

• Other wood-growing fungi (e.g. whitish oyster mushrooms, honey fungi, scalycaps) — It is described as hard to confuse: no other wood-dwelling gilled fungus has such a pure white, porcelain-glossy, slimy cap with a large drooping ring on the stem.

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 English names "porcelain fungus" and "poached egg fungus" refer to the white, slippery, glossy cap.
• It produces strobilurins – fungicidal compounds; the first crop-protection agents of this group were isolated from wood-dwelling fungi.
• Fruiting bodies growing on the underside of a trunk curve their stems so that the caps are held horizontally, with the gills facing down.
• The species was described in 1794 by Heinrich Adolf Schrader as Agaricus mucidus; the epithet refers to the layer of mucus on the cap.