Soil erosion control
One of the best adapted grasses to semi-arid conditions, Cenchrus ciliaris is valuable for erosion control in such places. In Australia, it was successfully planted for revegetation and erosion control in parks, reserves and river catchments from the 1960s to the mid-1970s (Payne et al., 2004; Albrecht et al., 1997). In a farm in Central Australia, using Cenchrus ciliaris in combination with ponding banks in a severely degraded area increased grazing capacity 10-fold after five years (Friedel et al., 2006). However, its tussocky nature does not allow for complete ground cover (FAO, 2010).
Weed
Cenchrus ciliaris is an aggressive grass due to its root system and allelopathic toxicity towards other seeds. It spreads readily and can out-compete native pastures in Australia and in southern USA. It is declared a noxious weed in several arid states of the USA, in Hawaii, in Mexico and in northern Australia (Ecoport, 2010; Friedel et al., 2006; Cook et al., 2005). Cenchrus ciliaris can significantly raise the fire hazzard (frequency and intensity) of an area to the point of removing competing shrubs and trees (Carter, 2006). In Australia, it is recommended for the control of calotropis (Calotropis procera) colonies thanks to its allelopathic effect on roots (Parsons et al., 2001). There have been many attempts to understand the spreading mechanism of buffel grass to help determine control strategies (Jackson, 2004). For example, it thrives in conjunction with legumes such as Desmanthus leptophyllus, Desmanthus virgatus, Desmanthus bicornutus, Leucaena leucocephala, Macroptilium atropurpureum, sicklebush (Dichrostachys cinerea), Stylosanthes hamata, Stylosanthes scabra, Stylosanthes seabrana and Stylosanthes humilis, because of the improved N status of the soil (Orwa et al., 2009; Cook et al., 2005).
Biodiversity
Cenchrus ciliaris has been declared an environmental weed in northern Australia and is thought to have a negative impact on biodiversity through competition, altered soil nutrients, water availability, shading, altered fire regimes and changes in availability of dispersal or pollination agents. It decreases the diversity of fauna through removal of flora diversity (Friedel et al., 2006).