Vetiveria zizanioides. This plant, commonly known as vetiver grass, is a clump grass originating in south India. There are many cultivars of vetiver grass but those originating in south India are sterile and non invasive.
This plant have a long and strong root system that is usually use for soil erosion control, slope protection, agriculture improvement and also wastewater treatment.
The Vetiver grass will tolerate high levels of nitrates, phosphates, heavy metals, and agricultural chemicals. Can be used for treating wastewater, rehabilitating mine tailings, stabilizing landfills and general rubbish dumps. The plants takes up the toxic materials and confines the contaminates to the effected area.
Here below some photos about applications for water treatment:
(photo: Truong, THE VETIVER SYSTEM
IMPROVING WATER QUALITY)
I also use vetiver in a research for aquaculture wastewater treatment with floating wetlands. And the Dick Grimshaw (Founder and Chairman of The Vetiver Network International) send me, when I was an university student, a lot of books and paper related to vetiver plants and his use. It was 1995.