Luzula arcuata

Tracheophyta MagnoliopsidaJuncaceaeLuzulaLuzula arcuata

Ecology

A dwarf, tufted, shortly rhizomatous and stoloniferous herb of bare windswept rocky summit ridges and plateaux that are mostly kept free of winter snow, where it often grows with Juncus trifidus. In high altitude corries it can occur in areas of snow-lie with greater vegetation cover. From 760 m (Slioch, W. Ross) to 1290 m (Cairn Toul, S. Aberdeen).

Status

Native

World Distribution

European Arctic-montane element, but absent from mountains of C. Europe; also in E. Asia and western N. America.

Broad Habitats

Light (Ellenberg): 9

Moisture (Ellenberg): 5

Reaction (Ellenberg): 2

Nitrogen (Ellenberg): 2

0

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 0

July Mean Temperature (Celsius): 10.8

Annual Precipitation (mm): 2044

Life form information

Height (cm): 10

Perennation - primary

Perennial

Life Form - primary

Hemicryptophyte

Woodiness

Herbaceous

Clonality - primary

Rhizome shortly creeping

Count of 10km squares in Great Britain: 22

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: -0.43

Distribution information

JNCC Designations

NBNSYS0000002245

Scarce Atlas Account

Scarce Atlas Account: 

Luzula arcuata Sw.

Curved wood-rush

Status: rare?

 

 

This plant is found in one of the most uncompromising habitats on the highest of the Scottish hills. It grows in open, stony fell-field and rock debris on windswept summit ridges and plateaux where protective winter snow is stripped away by the wind leaving a scoured and harsh niche in which only a handful of vascular plants can survive. It appears to be calcifuge, growing on coarse, leached alpine soils derived from granite, quartzite, granulite and acidic schists. The most frequent associates are Carex bigelowii and Juncus trifidus with, less frequently, Gnaphalium supinum and Luzula spicata. The moss Racomitrium lanuginosum is also a common associate along with some lichen species. In higher and more open carries L. arcuata can extend down into more snow-loving vegetation with Salix herbacea and a variety of mosses and liverworts. The altitudinal range is from 760 metres on Slioch up to 1290 metres on Cairn Toul, making this one of the most exclusively montane of all British plants.

L. arcuata is a perennial species with short stolons and a creeping rhizome system.

There is nothing to suggest that this species is under any threat and it probably still occurs in most of the 10 km squares for which only pre-1970 records were available. In its Cairngorm stronghold it is still locally frequent.

This is an arctic species with a circumpolar distribution. If reaches its southern European limit in Scotland.

As this species has been recorded in only 12 British 10 km squares since 1970, it qualifies for inclusion in the Red Data Book (Perring & Farrell 1983) under the current criteria. However, it will probably be recorded in more than 15 squares when, as seems likely, it is refound in some of its old localities.

 

 

G. P. Rothero

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 (324b)
Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols,
Hultén, E., and Fries M.
, Königstein, (1986)

Scarce plants in Britain,
Stewart, A., Pearman D. A., and Preston C. D.
, Peterborough, (1994)

British Red Data Books. 1. Vascular plants, edn 3,
Wigginton, M. J.
, Peterborough, (1999)