About this fungus
King Alfred's Cakes is a fungus in the Hypoxylaceae family. Its habitat and field characteristics are summarised below.
A hard, rounded or cushion-shaped fungus resembling a lump of charcoal on dead wood. Mature fruit bodies are dark brown to black and often grow in tight clusters, with a finely dotted or cracked surface.
What to check
A section through the centre reveals alternating pale and dark concentric bands. The outer layer contains many tiny flask-shaped spore chambers, visible at the surface as minute dots. There are no gills, pores, stem, ring or volva. The combination of charcoal-like exterior, solid banded interior and ash wood is especially useful.
Variation
Young fruit bodies are reddish-brown and relatively soft. They harden and blacken with age, then become dry, light and brittle after spore release. Old stromata can remain on the wood long after active growth has ended.
Lookalikes
Other Daldinia species share the dark rounded form and concentric interior, and modern work shows that host, microscopic features, chemistry and DNA can be needed for species-level separation. Kretzschmaria deusta forms flatter irregular crusts and lacks the same neat internal banding.
Habitat and range
Saprotrophic or weakly pathogenic on dead and dying broad-leaved wood. The modern European concept is strongly associated with ash, with occasional records on other hosts. Similar Daldinia on beech, oak and other trees, especially outside Europe, may belong to different species.
Food safety
Inedible.