Yellow centaury Cicendia filiformis

A member of the gentian family, yellow centaury is a tiny slender plant with a fleshy pinkish-green stalks.

Its flowers only open in the sun, revealing the four yellow petals (often tinged pink). It grows between two and twelve centimetres in height and has linear leaves two to six millimetres in length.

Distribution

In England, in recent years this native species has been restricted to heathland and culm grassland districts of Cornwall, Devon, Dorset, the New Forest and the Sussex Weald. It is now extremely rare in both Devon and Sussex and rapidly declining in Cornwall and Dorset. The key areas for this plant are the Lizard Peninsula and New Forest where it is still widespread. It is also present in Wales on the St David’s Peninsular grass heath commons and in south west Ireland.

Habitat

It is found around seasonally-flooded pools along rutted trackways and scrapes on wet grass heath with sandy or peaty soils. More rarely, it is also present in tightly grazed seasonally-damp acid grassland and serpentine erosion pans, woodland rides, dune slacks and coastal cliffs. The key element is the open nature of habitat with reduced competition allowing this tiny annual to complete its life cycle.

Status

Classified as ‘Nationally Scarce’ and is included as a species “of principal importance for the purpose of conserving biodiversity” under Sections 41 (England) and 42 (Wales) of the Natural Environment and Rural Communities Act 2006.

Key threats

Many populations were lost due to heathland reclamation and drainage, though more recently, cessation of grazing, infilling of ephemeral water bodies and upgrading of muddy trackways with hardcore have posed greater threats.

Best time to see

August and September when flowering.