Photographs: Inishannon, Co. Cork

Knotgrass sub species Polygonum aviculare subsp. littorale Family: Polygonaceae Flowering time: July - October. Annual. Native A coastal sub-species of Knotgrass, P. aviculare but it has smaller flowers, leaves without recurved margins and prostrate growth. Mature fruits project from the old flowers but they are shorter than those of Polygonum oxyspermum. Found on coastal sand and shingle. Identification by Alan Silverside, BSBI Similar: Ray's Knotgrass, Polygonum oxyspermum has larger fruits and flowers and leaves with recurved margins

Knotgrass, Polygonum aviculare subsp. littorale