An annual, rarely perennial, rootless twining herb, parasitic on the stems of a wide variety of small shrubs and herbs (most frequently Calluna vulgaris, Thymus polytrichus, Ulex gallii and U. minor) on heathland, chalk downland and fixed dune grasslands. It is also casual on field crops and in arable field-borders at the northern and western extent of its range. Lowland.
The loss of lowland heath, ploughing of chalk downlands, and an increase in scrub have caused a decline in this species since 1930. Whilst it is still locally abundant, the map suggests a continuing substantial decline.
Eurosiberian Southern-temperate element; widely naturalised outside its native range.
Light (Ellenberg): 7
Moisture (Ellenberg): 6
Reaction (Ellenberg): 2
Nitrogen (Ellenberg): 2
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): 4.3
July Mean Temperature (Celsius): 15.9
Annual Precipitation (mm): 846
Count of 10km squares in Great Britain: 494
Count of 10km squares in Ireland: 27
Count of 10km squares in the Channel Isles: 12
Atlas Change Index: -1.28
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.