Cauliflower fungus

Description

The brain fungus (cauliflower fungus) is a large, spherical mushroom resembling a cauliflower or a sea sponge: from one thick base grows a thicket of wavy, flat, cream or yellowish lobes. It is usually 10–30 cm wide, and individual specimens may be much larger. Young it is white or cream, darkening with age to ochre and yellow-brown. The flesh is waxy, pale, with a pleasant, nutty smell.

It grows at the base of trunks and on the roots of conifers, most often pines, from summer to autumn. It is a parasite and a cause of brown rot of wood, so it is always found by a tree, often growing deep into the substrate. One fruiting body usually grows once a year, but it may reappear on the same tree in successive years.

It is most easily confused with the oak cauliflower fungus (Sparassis brevipes), which has wider, more leaf-like branch tips. Much of the data on edibility is based on young, fresh specimens. If you are not sure of the species, do not pick or eat it.

Identification features

Cap

No typical cap. Fruiting body irregularly spherical, height usually 5–20 cm, width 6–30 cm (some descriptions give up to about 24 cm), sometimes larger. From a thick, fleshy base spread leaf-like, wavy, variously fused branches with toothed edges, resembling cauliflower or lasagne pasta. In young specimens whitish, later yellowish, cream, ochre or yellow-brown. Young lobes hard and rubbery, later soft.

Hymenophore (underside of the cap)

The hymenium covers both sides of the lobes of the fruiting body; no gills, tubes or spines.

Stem

The branches grow from a thick, blackish stem base, often growing deep into the substrate (tree roots).

Flesh

Waxy, elastic, white. General rule: do not taste the flesh of unidentified mushrooms).

Spore print and spores

Spore print ochre to cream. Spores smooth, short-ellipsoid to oval, pale yellow. Size: 5–7 × 3.5–7 µm (descriptions give different ranges).

Habitat and distribution

Ecology. Parasite or saprotroph causing brown rot of wood. Grows on roots and at the base of trunks of conifers, living and dead: most often pines, less often spruce, also Douglas fir, larch and others. In affected trees the trunk rots up to a height of about 3 m, and the tree gives off a smell of turpentine. Usually one fruiting body a year; on the same tree fruiting bodies appear intermittently in successive years.

Distribution. Coniferous and mixed forests of temperate Europe (not in the boreal zone). In Poland formerly regarded as rare; Red List 2006: R (potentially threatened), although some descriptions say that in Poland it is fairly frequent. Until 9 October 2014 under strict protection, now removed from the list of protected fungi (Dz.U. 2014 item 1408) - without legal protection. It is on the lists of threatened species in, among others, Belgium, Estonia, Lithuania, Norway and Latvia.

Fruiting. From July to November; in Poland mainly in autumn (no more precise data).

What can it be confused with?

• Sparassis brevipes (oak cauliflower fungus) — More faded, wider and more leaf-like branch tips; less wavy, zoned lobes and no clamp connections.
• Sparassis radicata (North America, possible synonym) and S. spathulata — North American species; 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

• In 1711 in Turoszów a forester reportedly found two specimens; the larger one was said to weigh 20 kg and measure 2.55 m (an account hard to verify).
• From 1990 it was a strictly protected species in Poland; from 9 October 2014 it was removed from the list of protected fungi.
• In affected trees the trunk rots up to about 3 m in height, and the tree smells of turpentine.