Ficinia nodosa

Ficinia nodosa, a grass-like sedge, grows to roughly in height, with its smooth, green-yellow stems spreading up to in diameter. The stems themselves grow to between in length and in diameter. The fruit, found within the flower-heads, are an irregularly shaped dark brown to black nut with a diameter of approximately 1 mm. Ficinia nodosa (female phase) - Flickr - Kevin Thiele.jpg|female phase Ficinia nodosa (male phase) - Flickr - Kevin Thiele.jpg|male phase == Taxonomy ==

Ficinia nodosa has a complicated taxonomic history, with several synonymic names, including the basionym Scirpus nodosus, as well as Isolepsis nodosa, Holoschoenus nodosus, Scirpoides nodosus, and ethel sedge. Further examination of specimens of nodosa collected in Tasmania and King George’s Sound was done by Robert Brown in 1802 and 1805 respectively. reclassified the species as Scirpus once again. The decision to include nodosa in the Ficinia genus greatly extended the range of distribution of Ficnia. Despite the classification as Ficinia due to the presence of a gynophore and distribution, some researchers suggest a wider range of plants of similar structure need to be studied to come to a decisive agreement about F. nodosa. == Distribution and habitat ==

Ficinia nodosa is known to grow natively in South Africa, Australia, and New Zealand, including the Kermadec, Three Kings, Stewart, and Chatham Islands. and in Namibia. In South Africa, F. nodosa grows across the east coast, though some evidence suggests the distribution includes the Northern Territory. and does best in direct sunlight, with access to some water. In sand dune environments, nodosa often grows in dense clumps on backdunes. The plants establish themselves through windborne seeds carried to an area, before expanding utilising rhizomes and new seeds. Reports of specimens of F. nodosa growing in Chile exist, though more research is needed to determine whether the plant is native to the region. == Ecology ==

F. nodosa is a long-living rhizomatous perennial with flowers growing in the summer and often remaining on the plant throughout the year, giving the appearance of year-round flowering. The sedge grows alongside several native plants in New Zealand dune ecosystems, such as sand coprosma (Coprosma acerosa), prostrate snowberry (Pernettya macrostigma), and tauhinu (Ozothamnus leptophyllus). One study found that the growth of F. nodosa plants was inhibited by a process known as allelopathy, whereby the chemicals produced by one species limit the growth of surrounding species. On New South Wales coast in Australia, F. nodosa appeared to be inhibited by the presence of bitou bush extracts in the soil in which the plant was growing. Bitou bush is an invasive species which was planted in dune ecosystems in an attempt to stabilise the sand dunes between 1946 and 1964. Further tests showed that chemicals extracted from Acacia longifolia roots and soil also inhibited the growth of seedlings of F. nodosa. Despite F. nodosa being widespread and common across the Southern Hemisphere, in coastal regions of New South Wales F. nodosa competes with both the invasive bitou bush and native dominant species Acacia longifolia. == Uses ==

Research has shown that F. nodosa could be utilised in biofiltration systems such as constructed wetlands to remove heavy metals, 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. The Māori people utilised several native sedges and similar plants, including F. nodosa, to thatch the roofs of Wharenuis. F. nodosa is commonly recommended as a sand binder or as a mixed landscape feature around bodies of water such as filtration beds and ponds in the native regions of Victoria, and South Australia. Furthermore, F. nodosa is often found to control sand movement in dune slacks due to its binding abilities, and therefore, is often used in dune restoration projects within its native range. ==References==