Corallorhiza trifida

Tracheophyta MagnoliopsidaOrchidaceaeCorallorhizaCorallorhiza trifida

Ecology

A saprophytic herb usually found in shaded, damp, Alnus and Salix carr on raised mires and lake margins, but which also occurs in dune-slacks with Salix repens. More rarely, it grows in tall-herb fen, in Betula and Pinus woods (amongst Sphagnum) and on moorland. It may colonise secondary habitats, including plantations and quarries. 0-365 m (Braemar, S. Aberdeen).

Status

Native

World Distribution

Circumpolar Boreal-montane element, with a continental distribution in W. Europe.

Broad Habitats

Light (Ellenberg): 5

Moisture (Ellenberg): 5

Reaction (Ellenberg): 5

Nitrogen (Ellenberg): 4

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 2.5

July Mean Temperature (Celsius): 13.5

Annual Precipitation (mm): 956

Height (cm): 22

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: 102

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: 0.61

JNCC Designations

NHMSYS0000457493

Scarce Atlas Account

Scarce Atlas Account: 

Corallorrhiza trifida Chatel.

Coralroot Orchid

Status: scarce

 

This saprophytic orchid is most often found amongst moss cushions and thick leaf mould in damp pine and birch woods (including pine plantations where it grows with Goodyera repens and Moneses uniflora), and in willow and alder carr. Deep shade is not essential though, and C. trifida also grows in the open in damp dune slacks, invariably with Salix repens and sometimes with Juncus balticus and Schoenus nigricans. Less typically it has been found in tall herb fen, with young Salix cinerea, amongst Carex spp. and on sphagnum hummocks; on dunes with Ammophila arenaria, where the water table is near the surface; amongst rank Molinia caerulea; in heather moorland; and under willows on the damp stony ledges of a quarry. It seems to have exacting water table requirements, sometimes growing only by tree bases, or following the margins of a dune slack. It is normally found in the lowlands, but reaches 365 metres at Braemar. 

Plants survive as underground rhizomes except while flowering for a few weeks between April and August (usually in June and July). Most flowers set seed. Self-pollination is normal, though insects are attracted by the slight scent and may cause some crosspollination. The number of flower spikes can fluctuate wildly from year to year but it is not clear what causes this fluctuation. Vegetative reproduction occurs by fragmentation of the rhizome.

C. trifida is inconspicuous and easily overlooked, and large new populations are still being found. Fluctuating numbers of flowering spikes may lead to populations appearing to vanish in some years.

C. trifida is a circumboreal species. In Europe it is found from northern Scandinavia south to the Pyrenees, northern Italy, northern Greece and the Crimea.

C. trifida is extremely unusual in obtaining its nutrients by photosynthesis, parasitism and saprophytism.

 

E. J. MacKintosh

Atlas text references

Atlas (336a)
Allan B, Woods P
1993.  Wild orchids of Scotland.
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Meusel H, Jäger E, Weinert E
1965.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.