A small annual or short-lived perennial which grows in shallow water or on wet soil. Typical sites include the margins of ponds and ditches, flushes, damp depressions, gateways and tracks in pastures and on heathland, and the sheltered backwaters of rivers. Unlike R. hederaceus, it is confined to acidic, mesotrophic or oligotrophic soils. 0-1005 m (Carnedd Llewelyn, Caerns.).
R. omiophyllus remains frequent in W. Britain and S. Ireland, where there are many more records than there were in the 1962 Atlas. The decline at the fringes of its range was already discernible in the 1962 Atlas, and is now much more marked.
Suboceanic Southern-temperate element.
Height (cm): 9
Perennation - primary
Perennation - secondary
Life Form - primary
Life Form - secondary
Comment on Life Form
Clonality - primary
Clonality - secondary
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.