Latin acetosellus—slightly acid or sour, referring to the taste of the leaves.
Erect perennial with spreading slender rhizomes. Leaves not jointed, stalked, mostly arrow-head shaped. Sheath papery, splitting. Sexes mostly on separate plants. Flowers in narrow clusters. Perianth segments 6, not winged, ridged or toothed, outer 3 largest. Stamens 6. Style with 3 branches at tip. Fruit a 3-angled nut enclosed in persistent perianth.
Widely naturalised cosmopolitan weeds.
4 species from temperate Eurasia.
Source: (1997). Polygonaceae. In: . Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.