An annual or biennial of sandy fields, dune-slacks and waste ground; now restricted as an apparent native to the Channel Islands, the margins of two recently created pools in Norfolk and an area of excavated shingle in Kent. Recent records elsewhere are mainly of casual plants on waste ground, although it is thriving on tracks and a rubbish tip in Dorset. Lowland.
G. luteoalbum was first recorded in 1690 and became extinct at all its presumed native Breckland sites in the early 20th century. It was discovered in E. Kent in 1996.
Eurosiberian Southern-temperate element, reaching its northern limit in S. Sweden. It is widely naturalised outside its native range.
Count of 10km squares in Great Britain: 7
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 7
Atlas Change Index: 0.23
RDB Species Accounts
Gnaphalium luteoalbum L. (Asteraceae)
Jersey cudweed, Edafeddog Melynwyn
Status in Britain: CRITICALLY ENDANGERED. WCA Schedule 8.
Status in Europe: Not threatened.
G. luteoalbum is a plant of sandy fields, waste places and sand-dunes, now found as a probable native plant only in Norfolk, but formerly occurred rather more widely in the Breckland of Norfolk, Suffolk and Cambridgeshire. In Norfolk, it occurs in a small area of sand-dune on the north coast, where two small colonies still exist. Both are on the margins of man-made hollows ('slacks') which were excavated in 1978/9, 1983/4 and 1992/3 to create shallow pools for natterjack toads, the newly-created habitat proving to be of unplanned benefit to G. luteoalbum (Scampion 1993).
The two Norfolk colonies are within enclosures fenced against cattle, but rabbits graze within them. The pools are shallow and seasonal, often drying up in late summer, and flooding to variable levels in winter, these fluctuations helping to maintain open conditions suitable for germination. The substrate is predominantly sand containing little organic content, with a pH between 6.5 and 6.8. Common species of the margins include Agrostis stolonifera, Carex arenaria, Centaurium erythraea, Festuca rubra, Lotus corniculatus, Potentilla anserina, Prunella vulgaris and annuals such as Erophila verna and Linum catharticum.
G. luteoalbum is a short-lived herb, sometimes behaving as an overwintering annual, though flowering in autumn rather than spring (Watkinson & Davy 1985). In that case, flowering is from July to September (occasionally as late as November), seedlings normally appearing in September and October, and the overwintering rosettes becoming dormant in December. However, this strategy does not appear to be constant; for instance, large recruitment of seedlings has been noted in May. Rather, the species seems to be opportunistic in its germination behaviour, almost certainly correlated with the seasonal fluctuation of water levels in the pools (Scampion 1993). The plant may also behave as a strict biennial. Germination tests have indicated that a high percentage of seeds are viable, and the behaviour of wild populations suggests that a persistent seed-bank exists. For example, prior to excavation in 1978, no plants had been seen at the present location since 1967.
Populations of the two colonies fluctuate annually depending on the availability of open ground for germination. The need for open ground was amply demonstrated when, between 1989 and 1992, ponds dried completely. The succession to a community dominated by dense perennial grasses was rapid, and the loss of ground suitable for germination was quickly reflected in the numbers of plants recorded in one colony: from more than 300 in 1989, to 47 in 1991, and only 15 in 1992. In a different sample plot in 1991, between 47% and 75% of the plants flowered, producing copious seed.
The status of G. luteoalbum in Britain has been debated ever since its first discovery in 1820 but, in view of its historical distribution, it seems reasonable to assume that it is native in East Anglia. The large colony in Dorset, discovered in 1978 on tracks, and which has spread in vast numbers to an adjacent munitions waste-tip is probably not of native origin. In 1996 a population of about 100 plants appeared in the RSPB reserve at Dungeness, growing in a hollow where shingle had been excavated and into which silt washings had been pumped. The species had not been known previously in Kent, and its origin is uncertain. However, it grows in coastal habitats on the nearest parts of the French coast, and it is possible that seed may have been carried over the Channel by birds. Terns, at least, are known to ‘commute’ between their colonies at Dungeness and those on the coast near Calais.
Overseas, it occurs throughout Europe, north to southern Sweden and Latvia, extending to west and central Asia.
M. J. Wigginton
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.