Candlesnuff fungus

When: Autumn and winter

Scientific name: Xylaria hypoxylon

Also known as: Candlestick fungus, carbon antlers

Height: Fruiting bodies grow to around 8cm in height

Where: On rotting tree stumps in woodlands; FCS Devilla Forest, Gartmorn Dam

The evocative name of the candlesnuff fungus is reflected in its appearance; the ashy tones of the withered stalks could almost represent a snuffed candle wick, eerily dotting the decaying tree stumps of quiet, empty woodlands...

Candlesnuff fungus is a one of the flask fungi, characterised not by appearance (as they vary hugely) but in the microscopic details of the compartments in which their spores develop, or 'asci'. This particular species is a type of wood rotter, containing enzymes that break down the wood, returning nutrients to the soil and taking just enough for the fungus itself to survive. Without wood rotting fungi, we would all be stuck under years' worth of fallen trees and leaves, so they are hugely important to our ecosystems! As with most fungi, the main part of the organism is spread out in a tiny network of tubes known as mycellium (almost like the roots of a tree) in the wood itself, with the visible parts of the fungus poking above the outer surface of the wood known as the 'fruiting body'. Although this mostly appears as a pale grey stalk, it can turn black in the winter months.

Most visible in autumn and winter, candlesnuff grows on fallen branches or tree stumps of mainly broadleaves trees, although it can occasionally be found on coniferous wood. There are other wood rotter species that preceed the presence of candlesnuff, some examples being honey fungus (Armillaria mellea) and sulphur tuft (Hypholoma fasciculare). Each different species targets a different part of the wood to break down; candlesnuff specialises in decaying some of the minority elements of wood, meaning that it is easier for it to access these components once other major parts have been digested by other fungi first.

This species of fungi is in fact bioluminescent, meaning that it has the ability to produce and emit light. In this instance, the light is very faint, not visible to the human eye. It is said that to see a bioluminescent fungus glowing, it is best to chop a piece of wood that is being decayed in half, as the light produced by the mycellium is often brighter. This almost unearthly phenomenon may explain why candlesnuff fungus, and the entire fungi kingdom in general, has historically been associated with spiritual beliefs and fairy tales. The reason for the fungal bioluminescence is still largely unknown, although some researchers speculate that it is an attempt to attract grazers, aiding the fungi in spore dispersion around the forest.

Find out more about this and other fascinating fungi at

Image: Adam Ross

More Info

  • Season: All Year Round
  • Species Group: Plant