Spread of introduced Lehmann lovegrass along a grazing intensity gradient

Changes in density of Eragrostis lehmanniana and native grasses, and the proportion of lovegrass present along a livestock grazing intensity gradient were measured, on the Santa Rita Experimental Range, Arizona. The gradient included grazing exclosures and plots radiating away from a cattle watering point. Lehmann lovegrass spread from sowings 4 km from the water point and an average 1.8 km from the exclosures. Lovegrass density increased with time but was not affected by different grazing intensities. Native grass density decreased, and lovegrass relative abundance increased with time and as grazing intensity increased. Livestock grazing was not necessary for Lehmann lovegrass to spread, but the lovegrass relative abundance was greater at higher grazing intensities. -from Authors