An annual or possibly perennial herb, parasitic on Achillea millefolium. It typically occurs on dry, somewhat basic soils in cliff-top grassland and on roadsides and grassy banks, usually near the sea. More rarely, it occurs in disturbed artificial habitats. Flowers can reappear after decades of absence, suggesting that the seeds are long-lived or that plants can persist without flowering for many years. Lowland.
In recent years the loss or decline of some populations of this species has to some extent been balanced by the appearance, or re-appearance, of others. The population at Maryport docks (Cumberland) has increased rapidly since it was first found in 1983.
European Temperate element.
Count of 10km squares in Great Britain: 25
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 12
Atlas Change Index: 0.5
RDB Species Accounts
Orobanche purpurea Jacq. (Orobanchaceae)
Purple broomrape, Gorfanc Glasgoch
Status in Britain: VULNERABLE.
Status in Europe: Not threatened.
O. purpurea is found mainly on dry, unmanaged and undisturbed grasslands, on soils which are at least slightly basic. The more natural habitats include cliff-top grassland, and many records are from roadside verges and banks which have escaped disturbance. However, it is also a plant of disturbed habitats occurring, for instance, in rough grassland on a reclaimed industrial site, on the level top of a river embankment, and by a car-park. Its grassland habitats are varied, and include both tall rank swards dominated by Arrhenatherum elatius, and shorter swards in which Agrostis capillaris, Dactylis glomerata, Elytrigia repens, Festuca rubra or Holcus lanatus may be prominent. Among a wide range of associates, usually undistinguished, are Centaurea nigra, Cruciata laevipes, Daucus carota, Heracleum sphondylium, Hypochaeris radicata, Hypericum perforatum, Lotus corniculatus, Plantago lanceolata and Rhinanthus minor. Orobanche minor occurs with it at some sites.
O. purpurea is parasitic on Achillea millefolium. It is an annual or short-lived perennial, with a flowering period extending from the end of May until August. Seed production is prolific, though seed may be poorly dispersed. Like other Orobanche species, it is thought that seed can remain viable for long periods in the soil, and this assumption is supported by the re-appearance of plants at former sites after long absences. The flowers may normally be self-pollinated.
Despite the abundance of its host plant, O. purpurea is very localised. Between 1990 and 1994 it was recorded from seventeen localities in Dorset, Hampshire, the Isle of Wight, Suffolk, Norfolk, Kent, Pembrokeshire and Cumbria. It has been lost from its natural sites in Lincolnshire owing to land-fill, though it was successfully translocated to nearby sites where it continues to thrive. Most extant populations are small, ranging from a single spike to a few tens of individuals. However, more than a hundred flower spikes have occurred in one population in the Isle of Wight (Everett 1988), and newly discovered populations at Maryport docks are large and increasing, with up to 360 spikes recorded in 1993. It has also reappeared in counties where it was thought to be extinct as, for instance, at a previously known site in Dorset after an absence of 40 years, and at Manorbier in Pembrokeshire in 1991, also after a gap of 40 years. The appearance of this plant may be erratic at many of its sites, in some years appearing in very small numbers or not at all.
Inappropriate grassland management and land development are potential threats to some populations. The rapid erosion of coastal cliffs threaten the largest Isle of Wight population and some colonies in Norfolk.
O. purpurea occurs throughout Europe (to central Russia) and is not uncommon in the Mediterranean region. However, it appears to have declined sharply in the northern parts of its range, and is threatened in several countries, including Germany, Poland and the Low Countries. It is still locally frequent in some of the Channel Islands.
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
1986. Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
1991. An account of Orobanche L. in Britain and Ireland. Watsonia. 18:257-295.
1999. British Red Data Books. 1. Vascular plants, edn 3.