Inonotus radiatus - Alder Bracket

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Polyporales

Nearly always associated with dying alder trees, the tiered form of this pored fungus differentiates it from the (usually more massive) rounded fruitbodies of the Oak Bracket, Inonotus radiatus. Often the Alder Bracket appears well above head height. White rot results from attack by the Alder Bracket.

The fruitbodies shown here are growing on the trunk of a riverside alder tree. This tough, inedible fungus is fairly common on many alder-fringed rivers in the British Isles.

Identification Guide

	Upper (infertile) surface Apricot coloured with slightly sunken reddish droplets near the margin when young, gradually turning brown and eventually almost black with age, with a pale rounded margin that becomes sharper as the fruitbody expands and matures. These semicircular or kidney-shaped brackets typically grow to 10cm diameter and stand out 3 to 6cm from the substrate wood. Their thickness is very variable but commonly in the range 1 to 3 cm; however, fruitbodies are nearly always tiered and they tend to merge one with another. The cap surface is finely velvety at first, becoming flesh is rusty brown and very tough.
	Tubes and Pores The rust-brown tubes, spaced at 2 or 4 per mm, are typically 3 to 10mm deep and terminate in silvery-cream irregularly rounded or angular pores. With age, the pores turn buff and then brown.
Spore print	Pale yellowish-brown.
Odour/taste	Odour not distinctive; taste bitter.
Habitat	On dead or dying deciduous hardwood trees, mostly alders but sometimes on birches and Beech and very occasionally on other hardwood trees.
Season	Annual brackets persist in blackened form throughout the year, but new young brackets generally appear in early to mid summer and release their spores during late summer and autumn.
Occurrence	Fairly common.
Similar species	Pseudoinonotus dryadeus, the Oak Bracket, produces larger brackets and weeps dark-honey-coloured droplets much more copiously; it does not usually produce tiers of fruitbodies.