Plant Guide > Mushrooms > Genus Armillaria > Armillaria Mellea

Armillaria Mellea

Honey-coloured Armillaria (Edible)

Armillaria mellea

Cap or Pileus - Colour from almost white to dark reddish brown. Young plants have numerous minute tufts or scales of brownish or blackish hairs. Margins sometimes striated. 1-6 inches broad.

Stem or Stipe - Usually reddish brown, paler above than below. Uniform in thickness, narrowed or slightly thickened at the base. Firm externally; soft and spongy, or hollow within. 1-6 inches long.

Ring or Annulus - Cottony to membranous, sometimes lacking in old plants.

Gills or Lamellae - Simply joined to the stem or running down it. White or whitish; sometimes variegated with reddishbrown spots.

Spores - White, elliptical.

Flesh - White or whitish. Taste unpleasant or acrid. Quality inferior.

Habitat - Common in woods or in cleared land, on the ground or on decayed wood. Solitary or clustered.

Time - Abundant in September. Found in June.

Var. obscura has cap covered with numerous small, blackish scales.
Var. flava has cap yellow or reddish yellow.
Var. glabra has cap smooth.
Var. radicata has tapering stem which penetrates the earth deeply.
Var. bulbosa has bulbous base.
Var. exannulata has cap smooth, margin even, stem tapering, annulus slight and evanescent, or wholly wanting.

The Armillaria mellea has a disagreeable taste when raw, but when cooked it is thought by some to be very good. Dr. Peck says he does not know of any unwholesome species for which it may be mistaken.

The Armillaria mellea has the habit, very unusual for a member of the group of Agaracales, of producing from its mycelial threads tuber-like masses of fungal substances from which the fruiting caps arise.

The fungal masses of the Armillaria, the so-called sclerotia, are ribbon or string like, and may be found between the wood and bark of cone-bearing trees.

These sclerotia send out cylindrical branches, called rhizomorphs, which may penetrate the soil and attack the roots of other trees, and so continue their work of destruction in the forest.

It is to the luminosity of these mycelial threads, which permeate the decaying wood, that the weird phosphorescent light in dense woods is due.