Description: C. humilis is a characteristic plant of recently disturbed sandy soils. It will also grow at the edge of dunes where there is some stability or on well-drained, soily embankments. It is one of Ireland’s smallest, cup-forming Cladonia species. The tiny, grey-green stems (podetia: to 0.5cm tall) are powdery sorediate above and inside the cups, but strongly corticate (with an outer skin) below. Brown discs are rarely present on the cup rim. It has an interesting chemical reaction: K+ yellow, which is unique in Europe among brown-fruited, sorediate Cladonia. Throughout Ireland.

Key Identification Features:

• Tiny, cup-forming podetia (0.5cm) that are sorediate above (K+ yellow) and corticate below for a short distance above the base
• On sandy, recently disturbed soils and dunes; discs very rare.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Cladonia humilis at iNaturalist World Species Observations database.