Sparganium erectum L.

Stems 66-160 cm high including inflorescence. Basal leaves erect, 77-160 cm long, 8-17 mm wide. Inflorescence with 4-6 branches, the terminal branch as long as or slightly exceeding uppermost 1 or 2 laterals. Male heads 8-14 mm wide at maturity, 7-13 per branch. Female heads usually 20-25 mm wide in fruit (including beaks), rarely 15 mm wide, absent from terminal branch, 1 or 2 per lateral branch, each positioned some distance above axil of a leaf-like bract or subtended by a very reduced bract. Perianth segments around fruit usually widened and thickened or spongy above, ±emarginate. Anthers 0.9-1.5 mm long, rarely 0.5 mm. Fruits 5.5-7 mm long, 4-5 mm wide, broadly obovate to broadly obtriangular, slightly to strongly ridged; ridges longitudinal, few to c. 12.

Grows from sea-level to 250 m alt. Forms dense stands in still or slow-flowing fresh water to 90 cm deep along backwaters or edges of streams, often in cleared grazing land.

Can be grown by divisions or seedlings.