Driving back from Stoer on 7th September 2018, I met David and Avril Haines on the road just east of the lowest bridge over the Oldany River (NC1033). David was in the adjacent woodland, with his camera trained on a fine group of gill fungi almost covering the rotten stump of an old downy birch. There were more than 30 brownish caps stacked one above the other, ornamented with darkish scales and shedding pale cream spores on those beneath them. The stalks were brownish towards the base, and each bore a quite substantial yellowish-white ring with darker tufts on its lower surface (see close-up).
The habitat, abundance and appearance all suggested one of the honey fungi Armillaria sp., a group of parasites and saprobes (feeders on dead organic matter) dreaded by gardeners and horticulturalists. Until the 1970s all were assigned to one species Armillaria mellea, but since then five or more species have been recognised, some only weakly or non-parasitic. Telling them apart is a task for the expert.
Accordingly, I collected a specimen, dried it and passed it on to our local mycologist Bruce Ing, who confirmed it as the dark honey fungus Armillaria ostoyae, a species that is uncommon in the south of the British Isles, but common in Scotland. Although still a parasite, in the wild, as here, it may be admired for its exuberant success in the important job of recycling old trees.
Ian M. Evans
Update 2 October 2018
A follow up visit on 2 October, 25 days after the first photographs were taken, revealed that the fruiting bodies themselves were now decaying. Having produced their spores they had served their purpose. Photograph showing the marked difference is attached.