Triangular club-rush  (Schoenoplectus triqueter)

Triangular club-rush is a critically endangered species in Britain. Both the common name and the Latin name triqueter (from the Latin triquetrus meaning three-cornered) (3) refer to the cross-sectional shape of the hairless stems, which have three corners (1). The plant mainly spreads by means of creeping rhizomes in Britain (6), and produces flowers at the top of the stem in groups called spikelets, which are in turn arranged in clusters known as inflorescences (1).