Description: Among the ‘powder’ lichens, this is the most common of those seen in the exposed upland parts of Ireland. The grey, granular thallus forms characteristic, rosette-like patches — sometimes with blackened centres — best observed on bare soil or on the low-growing mosses of our mountain ridges. It abhors limestone so will only grow where the rock types are siliceous. There are several chemically dissimilar forms so spot tests can vary. Widely distributed in siliceous upland sites; absent from Central Ireland.

Key Identification Features:

• Grey, ‘powder lichen’ with granular thallus, forming rosettes on mossy boulders, gravelly soils and mosses
• Well-drained, acid rock habitats on exposed mountain slopes.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Lepraria caesioalba at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Lepraria caesioalba at iNaturalist World Species Observations database.