Eleocharis quadrangulata square-stem spikerush Cyperaceae ELQU; R;

eleocharis-quadrangulata-paul-skawinski-flora-of-wisconsin-consortium-of-wisconsin-herbaria-wisflora-herbariu-wisc-edu

Eleocharis quadrangulata.© Paul Skawinski.Flora of Wisconsin.Consortium of Wisconsin Herbaria.wisflora.herbariu.wisc.edu

Eleocharis quadrangulata is a perennial C3 spikerush (Pascal-Antoine 2008), tufted, colonial from rhizomes, stems stout to 1 m tall, 0.2-0.6 cm wide, sharply 4-sided. 

Leaves bladeless, sheaths only. 

Flower spikelet cylindrical, 2-5 cm long about as wide as the stem, scales in 4 rows to 0.6 cm long, tip rounded, margins paper. 

Fruit a dry, achenes convex on both sides, widest above middle, brown, 0.2-0.3 cm, constricted above, tubercle flattened, tip pointed, about half to a third as long as achene, June-Oct. 

Wetland status: OBL. 

Frequency in NYC: Rare (G4; NYS S1, E). 

Origin: Native. 

Habitat: Shallow water along the coastal plain, often tidal soil pH 5.8-7.2 (USDA, NRCS 2010).