Common reed

Phragmites australis, the common reed, is a large, long-lived herbaceous grass in the family Poaceae, genus Phragmites — usually regarded as the only species of its genus. It has thick, vigorous rhizomes that creep through mud, forming dense reed beds; under favourable conditions the plant can gain 5 m or more in height in a single year. The upright, hollow, distinctly jointed culms are 2–6 m tall and about 1–2 cm thick. The leaves are arranged in two ranks, 20–50 cm long and 2–3 cm wide, linear and pointed, stiff and slightly rough. The inflorescence is a dense panicle, dark purple turning grey-brown, 15–50 cm long, made up of many small spikelets; later each flower bears long silky silvery hairs that help the minute seeds disperse by wind. Flowering usually occurs in late summer to autumn (about August–October in temperate regions).

Updated by lebachungtdh@gmail.com · 10/12/2026

The common reed has a nearly cosmopolitan distribution, growing in fresh and slightly brackish wetlands — along rivers, lakes, marshes, estuaries, ditches and paddy fields — from tropical to temperate regions. Its creeping rhizomes let it tolerate changing water levels and form reed beds hundreds of hectares wide, for example in the Danube Delta. Such beds are important wildlife habitat: many birds are strongly associated with reeds, such as the bearded reedling (Panurus biarmicus), the reed warbler (Acrocephalus scirpaceus) and the bittern (Botaurus stellaris). People have long used reeds for thatching roofs, fencing, mats, basketry, pulp and paper, particle board and biofuel; the rhizome (Chinese "lugen", 芦根) is a traditional medicine, sweet and cooling, used to clear heat, promote fluids, act as a diuretic and treat feverish thirst, vomiting and cough. Reed beds are also used in wastewater treatment and water filtration. In North America, the introduced European lineage grows more vigorously than the native one and is regarded as invasive, raising concerns for marsh ecosystems.

Updated by lebachungtdh@gmail.com · 10/12/2026