Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Species fact sheet Yellow Centaury Cicendia filiformis Yellow centaury is a member of the gentian family (Gentianaceae). It is a tiny slender plant 2-12 cm in height with a few fleshy pinkish-green stems and linear leaves 2-6 mm long. The terminal flowers only open in the sun, revealing the four yellow petals (often tinged pink). © Hans Hillewaert under Creative Commons BY-SA licence Lifecycle Yellow centaury is a short-lived spring germinating annual flowering in August and September. Seeds require sparsely vegetated or bare ground to germinate and plants are often present around the edge of temporary autumn/winter pools, and can be found in the draw-down zone around the edges during the summer. Habitat It is found around seasonally-flooded pools, along rutted trackways and on 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 on coastal cliffs. The key element is the open nature of habitat with reduced competition allowing this tiny annual to complete its life cycle. Distribution Yellow centaury distribution across Britain and Ireland The data used to create these maps has been provided under licence from the Botanical Society of Britain and Ireland (BSBI) and accessed from the Society’s online distribution database. In England, in recent years this native species has been restricted to heathland areas in 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 Peninsula’s grass heath commons and in south west Ireland. Some new populations of yellow centaury have recently been discovered in southwest England and Ireland off-setting some localised population losses. Species fact sheet Yellow Centaury Cicendia filiformis Habitat management for yellow centaury GB Status and rarity Conservation work to remove scrub along two adjacent trackways on the Lizard Peninsula in Cornwall resulted in the re-appearance of yellow centaury from buried seed. In 2011, these restored populations numbered over 4000 plants. Vehicle movements creating ruts on Dowrog Common in Pembrokeshire have also increased the habitat for this plant where access tracks have been used to facilitate management of the commons. Bare soil is maintained through cattle and pony grazing. Reasons for decline Yellow centaury is reliant on reduced competition with other plants, which is created by winter flooding, grazing and disturbance. Lack of management, in particular under-grazing resulting in ranker vegetation and scrub encroachment, will threaten the survival of this plant. Conservation should focus on reinstating extensive grazing to wet heathland sites where the species occurs or formerly occurred, combined with restoration and re-use of infrastructure features such as seasonally-flooded pools and trackways. Work should be targeted around or adjacent to surviving populations or at historical sites where yellow centaury is no longer present as the seed does have some longevity and may germinate once it is exposed following conservation works. Vehicle movements can create ruts which also help increase the habitat for this plant. Yellow centaury is classified as ‘Nationally Scarce’ (recorded in 16-100 hectads in Great Britain) and classified as ‘Vulnerable’ in The Vascular Plant Red Data List for Great Britain 2005 because of a significant decline in its area of occupancy. It is considered to be a good indicator species of habitat quality of lowland acid grassland and heathland mosaics and tends to occur with a variety of other scarce and declining plants including three-lobed water-crowfoot Ranunculus tripartitus, chaffweed Anagallis minima, allseed Radiola linoides and pillwort Pilularia globulifera. Historically many sites 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. For example, during the 1980s at least two key trackway systems on the Lizard were in-filled with hardcore to improve public access removing the temporary pools utilised by yellow centaury. Protection under the law This plant is included as a species “of principal importance for the purpose of conserving biodiversity” under Section 41 (England) of the Natural Environment and Rural Communities Act 2006. Survey method Individual plants are easily identifiable around temporary pools and a census should be undertaken. Where a large number of plants are present around a particular pool the population can be estimated. Like other annuals of this type, populations can fluctuate greatly from year to year with thousands of plants one season and none in some years with less favourable conditions. A single season’s data is therefore unlikely to be sufficient to judge the health of a population. © Lauren Tucker 14 Rollestone Street, Salisbury, Wiltshire, SP1 1DX. UK Tel: 01722 342730 [email protected] Funded by Natural England Speaking out for wild plants www.plantlife.org.uk Plantlife International - The Wild Plant Conservation Charity is a charitable company limited by guarantee. Registered in England and Wales, Charity Number: 1059559 Registered in Scotland, Charity Number: SC038951 Registered Company Number: 3166339. Registered in England and Wales.