File:Wood stained green by a fungus - geograph.org.uk - 997486.jpg

English: Wood stained green by a fungus. This small section of a fallen branch was stained green throughout its length, although the coloration is most visible in this photo at the right-hand side. Several other pieces of wood within a few feet of this one were likewise stained green.

The staining is caused by the fungal species Chlorociboria aeruginascens (Green Elfcup); as its common name suggests, it also produces fruiting bodies in the form of small green cups, but it is more common to encounter the dyed wood without the cups (as was the case here). Such green-stained wood was once highly valued; one of its uses was in a form of decorative woodwork called Tunbridge Ware.

By later returning to this area in the right season, I was also able to photograph the fruiting bodies of this species: 1524353.

"The Oxford Book of Flowerless Plants" (1966, 1979, Nicholson/Brightman) describes this species (under the older name of Chlorosplenium aeruginascens) and its blue-green cups, pointing out that it is often confused with the very similar species Chlorociboria aeruginosa. For more information on these species, see: http://botit.botany.wisc.edu/toms_fungi/jul2008.html and http://www.mushroomexpert.com/chlorociboria_aeruginascens.html