The alien invasive plants that form the scope of the research of this Division were introduced either intentionally (e.g. for ornamental use or agroforestry purposes) or accidentally (e.g. as ballast or in livestock feed). They have now become weeds in conservation areas and agricultural land, threatening the country’s biodiversity and agriculture. In addition, they can reduce runoff from water catchment areas, thus diminishing flow in streams and adversely affecting the water table. Download a leaflet that deals with weeds, alien plants and invasive plants, the problems they cause and ways of controlling them.