Sword-leaved helleborine (Cephalanthera longifolia)
|Also known as:||narrow-leaved helleborine|
|Size||Height: 40 - 60 cm (2) (3)|
The sword-leaved helleborine is listed on Appendix II of CITES (4).
The sword-leaved helleborine (Cephalanthera longifolia), also known as narrow-leaved helleborine, has white flowers with a yellow or orange-edged lip. Each plant may produce either a single or several upright stems, and the flowers occur in spikes. The dark green leaves are long and tapering, hence the common name (2) (3). This feature enables the sword-leaved helleborine to be distinguished from the similar white helleborine, Cephalanthera damasonium, which has shorter leaves (3) (5).
The sword-leaved helleborine has been widely recorded, but is scattered in Britain and Ireland and is rarely abundant (3) (6). It declined markedly in the 19th and 20th centuries (6), but strongholds remain in Hampshire, western England and western Scotland (3) (7). Elsewhere it occurs locally throughout much of Europe, North Africa and temperate Asia across to China and the Himalayas, but is local and rare in some countries, and is often common in Asia (2) (3).
A characteristic woodland glade species, the sword-leaved helleborine is found growing in calcareous soils in woodlands, particularly those in southeast England with a high proportion of beech trees (2) (3), but also occurs in rocky woodland and gorges, and is (rarely) found in sand dunes (7). It prefers more open patches with permanent light, especially south-facing rocky slopes and woodland rides and edges (3) (6).
This long-lived, perennial orchid flowers in May and June (2) (3). It tends to flower only if conditions are favourable, with sufficient light, and it can persist vegetatively in deep shade for many years (3) (7). It reproduces by seed. The flowers of the sword-leaved helleborine are pollinated by small solitary bees and are probably not self-fertile (3) (7). Fruit production is relatively poor (10 to 20 percent), but large numbers of seeds are set in capsules that do develop (3) (7). Seeds are wind-dispersed, and require a mycorrhizal fungal partner to develop (3) (7).
Although able to thrive in relatively shady conditions, if the canopy becomes too dense the sword-leaved helleborine could suffer (1) (3). The original decline of this species was thought to be largely caused by the decrease in coppicing in woodlands (7). Some sites have been lost due to habitat destruction, woodland conversion, inappropriate woodland management and collecting (3) (7).
The sword-leaved helleborine is included in Plantlife's Back from the Brink Campaign, and various management measures are underway at sites across Britain (3). The Royal Botanic Gardens, Kew have been working on propagation techniques for rare orchids, and this species is part of Kew’s Millennium Seed Bank project (3) (8). International trade in this species should be regulated under its listing on Appendix II of the Convention on International Trade in Endangered Species (CITES) (4), and the sword-leaved helleborine is also a UK Biodiversity Action Plan Priority Species (9).
To find out more about plant conservation, see:
Plantlife - Back from the Brink Campaign:
Information authenticated (April, 2002) by Royal Botanic Gardens, Kew.
http://www.rbgkew.org.uk/ and Tim Rich of the National Museums and Galleries of Wales.
- Calcareous: containing free calcium carbonate, chalky.
- Coppicing: traditional form of woodland management in which trees are cut close to the base of the trunk. Re-growth occurs in the form of many thin poles. Woodlands are cut in this way on rotation, producing a mosaic of different stages of re-growth.
- Lip: in plants, petal or petals that form a lobe.
- Mycorrhizal: a fungus that forms a close physical association with the roots of a plant, this relationship is mutually beneficial.
- Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.
- Pollinated: to transfer pollen grains from the stamen (male part of a flower) to the stigma (female part of a flower) of a flowering plant. This usually leads to fertilisation, the development of seeds and, eventually, a new plant.
- Rides: the footpaths and access tracks which run through and divide blocks of trees in woodland. Many rides contain a mixture of rich flora and structure, and provide different habitat conditions for a range of wildlife.
Rare Plants.co.uk (March, 2002)
- Grey-Wilson, C. (1994) Eyewitness Handbooks: Wild Flowers of Britain and Northwest Europe. Dorling Kindersley, London.
Platlife - Narrow-leaved helleborine (November, 2010)
CITES (November, 2010)
British Wild Flower Gallery (March, 2002)
- Preston, C. D., Pearman, D. A. and Dines, T. D. (2002) New Atlas of the Flora of Britain and Ireland. Oxford University Press, Oxford.
- Byfield, A. (1993) The Status and Ecology of Cephalanthera longifolia in Britain, with Conservation Recommendations. Plantlife and The Hampshire Wildlife Trust.
Royal Botanic Gardens, Kew (November, 2010)
UK Biodiversity Action Plan (November, 2010)