About

Ficinia nodosa, the knotted club-rush or knobby club-rush, is a rhizomatous perennial in the family Cyperaceae, native to South Africa, Australia, and New Zealand. Widespread in the Southern Hemisphere, Ficinia nodosa grows to between 15 and 220 cm in height.

Although it grows best in sandy, salty soil, the plant grows in a wide variety of environments from coastal sand dunes to alpine regions. F. nodosa’s appearance is characterised by dense clusters of long green stems topped with small, rounded flowers often remaining throughout the year.

Where it grows

Ficinia nodosa is known to grow natively in South Africa, Australia, and New Zealand, including the Kermadec, Three Kings, Stewart, and Chatham Islands. It is commonly found on the island of Saint Helena, in temperate areas of South America, and in Namibia.

Uses

Research has shown that F. nodosa could be utilised in biofiltration systems such as constructed wetlands to remove heavy metals, phosphorus and nitrogen concentrations in storm water runoff, particularly in saline environments, where F. nodosa occurs natively. Due to the plant’s ability to grow well in salt-water conditions, along with nodosa’s ability to collect large amounts of nitrogen in its shoots, the plant makes an excellent candidate for constructed floating wetlands in native regions. If grown alongside Phragmites australis, Sarcocornia quinqueflora, and Baumea juncea, the shoots and roots of the plant could be harvested to reduce nitrogen and phosphorus concentrations. F. nodosa is particularly effective for nitrogen removal due to its ability to sustain a constant level of nitrogen removal for salt concentrations below 10.4 mS cm-1.

Other Ficinia plants

Golden sand sedge · Clubrushes