Cyperus nutans is a sedge of the family Cyperaceae that is native to Australia, China, India, Bangladesh, south-east Asia, Malaysia, India, and Indonesia.[1]
The rhizomatous perennial sedge typically grows to a height of 1.5m (04.9feet). The culms are three sided with sharp edges and concave sides. The culms are typically up in length and have a diameter of . The leaves are usually shorter than the culms and have a width of around .[2] It blooms between February and July and produces brown flowers. Each compound inflorescence has six to ten primary branches up to a length of . The narrow-cylindrical spikes have a length of with a diameter. After flowering a dark brown narrow-ellipsoid to narrow-obovoid shaped nut will form.[2]
The species was first formally described by the botanist Martin Vahl in 1805 as part of the work Enumeratio Plantarum, from a specimen collected in India.[3] The only two subspecies are Cyperus nutans subsp. nutans and Cyperus nutans var. nutans.[4]
The plant is found in northern and eastern Australia in coastal areas in the states of New South Wales, Queensland, Northern Territory and Western Australia.[4] In Western Australia it is found around shady swamps and pools in the Kimberley region where it grows in sandy-clay soils. In New South Wales it is only found in the north-eastern corner where it is found along creek banks.[2]