Dark honey fungus

Description

The dark honey fungus is the most common honey fungus in Poland. The fruiting bodies have a cap 3–8 cm across, flesh-pink or reddish-brown, with distinct blackish-brown scales reaching the margin. The gills are cream-white at first, later brown, and the stem bears a fairly thick white ring with dark scales on the underside.

It grows in clusters on stumps and at the base of trees, mainly spruces, in coniferous forests on acidic soils, less often on fir, pine and beech. It is a parasite that destroys tree roots. Sometimes stumps are white with its spores.

Do not eat it raw or undercooked. Pick only specimens whose species you are sure of, because poisonous clusters also grow on stumps, e.g. the sulphur tuft.

Identification features

Cap

Diameter 3–8 cm; convex in young specimens, quickly expanding, becoming concave in older ones. Colour flesh-pink, reddish-brown or cream-brown. Characteristic fairly large, blackish-brown scales reaching the cap margin.

Hymenophore (underside of the cap)

Gills fairly crowded, cream-white at first, later brown; in some descriptions decurrent (running down the stem).

Stem

Height 4–12 cm, thickness up to 2 cm; cylindrical, fibrous, club-shaped, solid, often curved; in older specimens cottony and hollow inside. Whitish in the upper part, rusty lower down, usually with remnants of a whitish veil and brown fibrils. Ring fairly thick, white, with dark scales on the underside and at the edges, well developed.

Flesh

White, turning pinkish with age; mushroomy smell, mild taste. The raw flesh contains compounds harmful to some people (see: medical), so it must not be eaten raw.

Spore print and spores

Spore print white. Spores ellipsoid, smooth, with droplets, 7.5–10 × 5–7 µm.

Habitat and distribution

Ecology. A tree parasite (Armillaria root rot, white rot of wood) and a saprotroph on dead stumps and roots, sometimes on the ground near roots. It spreads by black rhizomorphs (“bootlaces”) under the bark and in the soil; the mycelium may show bioluminescence (glowing wood). It attacks mainly spruce, less often fir, pine and beech; highly pathogenic to many conifers.

Distribution. Northern Hemisphere: North America, Europe, Japan. Very common in Central Europe; in Poland the most frequent honey fungus species, especially in spruce forests on acidic soils. It is not legally protected in Poland.

Fruiting. Autumn; exact months — no data.

What can it be confused with?

• Armillaria mellea (honey fungus) — Grows on dead broadleaf trees, cap with very fine fibrils, sometimes entirely bare. From a mushroom picker's point of view all honey fungi are treated similarly.
• Armillaria tabescens (ringless honey fungus) — No ring on the stem; rare in Poland.
• Pholiota limonella — May be confused with it if mycelial fans are absent; detailed differences — 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

• A dark honey fungus individual from the Malheur National Forest in Oregon (USA), discovered in 2001, covers about 8.9–9.1 km² and is considered one of the largest living organisms on Earth; its age is estimated at about 8,000 years.
• The mycelium can glow (bioluminescence, so-called foxfire).
• In 2012 Poczta Polska (the Polish post) issued a stamp with the dark honey fungus (31 August 2012, face value 4.15 zł, in the series “Mushrooms in Polish forests”).
• Two scientific names were in use because Peck described the species as A. solidipes as early as 1900; the name A. ostoyae was conserved by a nomenclature committee resolution in 2011.