Pseudoraphis spinescens

Pseudoraphis spinescens, called spiny mudgrass or Moira grass is a rhizomatous and stoloniferous aquatic or semi-aquatic perennial grass, with ascending stems forming loose, floating mats in water to 1 m deep or more, or with stems to 50 cm high when not submerged. Moira grass (Pseudoraphis spinescens) was first described in 1810 by Robert Brown as Panicum spinescens, and subsequently transferred to Pseudoraphis by Joyce W. Vickery in 1950. Pseudoraphis spinescens is native to floodplains in Asia and Australasia, it is a C4 species, requiring seasonal cycles of prolonged, deep flooding interspersed with drying to achieve maximum growth and reproduction. Between flood events, P. spinescens forms a deep thatch of collapsed dry stems until flooding recurs and growth recommences. A study in southeastern Australia found that P. spinescens does not have a viable long-lived seed bank in floodplain soil, presumably regenerating from vegetative propagules and rootstocks. In the Murray-Darling B......read more on Wikipedia.