Cephalanthera longifolia

Tracheophyta MagnoliopsidaOrchidaceaeCephalantheraCephalanthera longifolia

Ecology

A rhizomatous perennial herb found in a variety of woodland types on calcareous soils, usually on chalk and hard limestone but also on calcareous schist in Scotland. It prefers permanent patches of light and is most frequent on steep, rocky slopes with an open tree canopy, but is also found along woodland edges and rides, and in scrub. Lowland.

Status

Native

World Distribution

European Temperate element; also in C. Asia.

Broad Habitats

Broadleaved, mixed and yew woodland

Light (Ellenberg): 5

Moisture (Ellenberg): 4

Reaction (Ellenberg): 7

Nitrogen (Ellenberg): 4

0

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.7

July Mean Temperature (Celsius): 14.7

Annual Precipitation (mm): 1166

Life form information

Height (cm): 60

Perennation - primary

Perennial

Life Form - primary

Non-bulbous geophyte (rhizome, corm or tuber)

Woodiness

Herbaceous

Clonality - primary

Little or no vegetative spread

Count of 10km squares in Great Britain: 131

Count of 10km squares in Ireland: 31

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: -0.77

Distribution information

JNCC Designations

NBNSYS0000002286

Scarce Atlas Account

Scarce Atlas Account: 

Cephalanthera longifolia (L.) Fritsch

Narrow-leaved helleborine

Status: scarce

 

 

This species is a light-demanding orchid of lowland woods on hard limestone, chalk and, more rarely, on other lime-rich substrates. It is found in a variety of woodland types, particularly beech and oak-ash. C. longifolia perhaps most typically occurs on steep slopes where the tree canopy is naturally thin and patchy, including limestone gorges, woodlands on limestone ridges or outcrops and chalk hangers. Well illuminated woodland rides and forest margins are also a favoured habitat, and it even occurs under conifers on dune sand where the canopy is sufficiently broken and on dumped chalk on heathlands. It has a poor ability to adapt rapidly to changing light intensities, and is not typically a coppice woodland plant, but instead is best regarded as a glade species where a broken tree cover permits relatively permanent high levels of light. The range of associates of C. longifolia is broad and typically includes Ajuga reptans, Dactylorhiza fuchsii, Epipactis helleborine, Fragaria vesca, Hedera helix, Ligustrum vulgare, Mercurialis perennis, Rosa arvensis, Sanicula europaea and Viola riviniana.

 

C. longifolia is a long-lived perennial with apparently poor reproductive abilities. It is cross-pollinated by small bees.

 

The plant has undergone a massive decline during this century, and has become rare in many former strongholds such as the Wye Valley. Today it is extinct in at least 23 vice-counties, whilst its hold in others is often tenuous indeed. Only a few colonies of over a few hundred plants exist, and most are declining or at best static. Collection has often been quoted as a principal cause of extinction at many sites; it certainly contributed to the plant's decline to extinction in the Durham magnesian limestone denes where it has not been reliably recorded this century (Graham 1988), whilst collecting severely reduced or eliminated one colony in Worcestershire as recently as the mid 1980s. However, natural, subtle changes in woodland composition and changes in forestry practice (principally resulting in reduced levels of insolation) probably account for most declines and eventual extinctions. C. longifolia is a difficult plant to conserve successfully in the long term: increased shading as the tree canopy closes soon results in a diminution of the population, whilst too much light results in desiccation of plants, together with a vigorous growth of competing coarse vegetation.

 

C. longifolia is widespread in southern and central Europe, extending north to 60° N in Scandinavia, with isolated occurrences in North Africa and east to the Himalayas.

 

 

A. J. Byfield

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.

Atlas text references

Atlas (331d)
Allan B, Woods P
1993.  Wild orchids of Scotland.
Curtis TGF, McGough HN
1988.  The Irish Red Data Book. 1. Vascular Plants.
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.