Do native grasses emerge and establish in areas rehabilitated using vetiver grass?

Species-rich grasslands provide important ecosystem services, and in South Africa, approximately 40% of these are degraded. Vetiver grass (from India) is often used during rehabilitation efforts to restore soil function without a thorough understanding the potential negative ecological impacts. Hence, study was initiated investigate vetiver’s impacts grassland rehabilitation. Firstly, field survey conducted using contiguous quadrat method evaluate extent secondary succession rehabilitated sites. Secondly, effect vetiver competition seed sowing on recruitment two native grasses (Eragrostis curvula Megathyrsus maximus) examined pot trials. The results showed no evidence succession, but rather abundance bare ground around vetiver, marked increase species richness with increasing distance from planted vetiver. Subsequently, trial, facilitated emergence both grasses, surface indigenous seeds greater than other methods. However, inhibited seedling establishment, even when root excluded. This suggests that areas unlikely become productive good grazing, because inhibits colonisation by grasses.