A long-lived rhizomatous perennial herb of well-drained sloping sites in deciduous woods, particularly those of Fagus, on calcareous soils. It is a poor competitor and does not form large colonies. Flowers are rarely produced and seed-set is very low, possibly due to the rarity of suitable pollinators. Lowland.
This elusive species has always been rare and is now found at only three sites, with a total of perhaps only thirty plants. Current conservation management includes removal of shrubs and trees. Native populations may soon be augmented with plants grown ex situ.
European Temperate element.
Count of 10km squares in Great Britain: 10
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 0
RDB Species Accounts
Cephalanthera rubra (L.) L.C.M.Rich. (Orchidaceae)
Red helleborine, Caldrist Coch
Status in Britain: CRITICALLY ENDANGERED. WCA Schedule 8.
Status in Europe: Vulnerable.
This species occurs in deciduous woods, principally of beech, on calcareous soils where the ground flora is sparse. Other trees and shrubs may include ash, elm, hazel, privet, sycamore, whitebeam and yew. Three other orchid species Cephalanthera damasonium, C. longifolia and Epipactis helleborine, typical of this habitat, are present in one or other of its sites. It is intolerant of competition from other plants (Bateman 1980), but other species occurring sparsely in the general community include Anemone nemorosa, Brachypodium sylvaticum, Campanula trachelium, Euphorbia amygdaloides, Hedera helix, Hieracium species, Hyacinthoides non-scripta, Lonicera periclymenum, Mercurialis perennis, Sanicula europaea and Viola riviniana. All colonies of C. rubra are on well-drained sloping ground, but not with any common orientation.
According to Irmisch (1863) the plant has a long life cycle, with the first foliage leaves appearing in the sixth year, and the first flowers in the tenth. Flowers, when produced, appear in June and July, but only a few shoots may produce flowers. Seed-set is very low in Britain, presumably because of the limited opportunity for natural pollination, though bees and hoverflies have occasionally been observed visiting the flowers. The flowers lack nectar, but in studies on the island of Gotland, Nilsson (1983) suggested that it uses 'floral colour mimesis' to attract bee pollinators. He linked certain Campanula species to the pollination biology of Cephalanthera rubra, and showed that in the bee-spectrum their colours are almost identical. He also showed that seed-set in Cephalanthera rubra was lower in the absence of the bees Chelostoma campanularum and C. rapunculi which visit both Campanula and Cephalanthera rubra. However, though C. campanularum has been seen visiting C. rubra plants in Hampshire, this species is thought to be too small to effect the removal of pollinia, and C. rapunculi is not known in Britain (G.R.Else, in litt.). If a similar link between Campanula and C. rubra exists in Britain, then other pollinators will be involved.
During the nineteenth century, C. rubra was found at several sites in Gloucestershire, and there have also been unconfirmed records from Somerset, Sussex and Kent. C. rubra now occurs only at single sites on chalk in Buckinghamshire and Hampshire (Rose & Brewis 1988), and one site on oolitic limestone in Gloucestershire. Its appearance, and especially flowering, has been sporadic at all three sites. For example, between 1955 and 1986 at the Buckinghamshire site, flowering occurred in only five of the 26 years when monitoring took place (Everett 1988). The number of individual plants is always small, the largest recent count being twenty at one site in 1990 (though 34 were noted in Buckinghamshire in 1958). The British population currently totals only about 30 plants.
Recent management has included the removal of invasive shrubs such as Ligustrum vulgare and Rubus fruticosus, and the selective felling of trees to allow more light to the ground. This seems to have promoted flowering. Leaf litter has been removed from one site, and slug pellets scattered around the plants to control predation. Hand-pollination has been carried out to a limited extent, and research into germination and propagation is being undertaken at Kew, with a view to supplementing wild populations with plants grown ex situ. Plants may become small if the habitat is overgrown, and even disappear, but it is suggested that the mycorrhizal rhizome system may remain alive for a long time (Sell & Murrell 1996).
Though widespread in Europe, reaching northwards to southern England and Finland, it also occurs eastwards to Turkey and Iran. C. rubra is vulnerable over much of its range, and is legally protected in several central and northern countries. It is mainly found in beech and other deciduous woodland, principally in dappled shade or in open areas which receive direct sunlight for part of the day. It is also encountered on steep, barish roadside verges. It seems never to occur in large colonies, but always as small groups or scattered individuals.
PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.