Photographs: The Gearagh Co.Cork
White flowers, 4-petalled, 3-4mm, stamens protruding. Leaves in whorls, oblong-elliptical, single-veined, 20-35mm long. Square stems. Hairless. Height to 1m.
Similar to Common Marsh-bedstraw but taller and with stronger growth.
Wet ground. Lake, pond, marsh edges, reed beds.
Identification confirmed by Paul Green
Great Marsh-bedstraw. The Gearagh, Co.Cork.