The influence of residual stems on biting rates of cattle grazing Eragrostis lehmanniana Nees

On semi-arid rangelands, stems and other standing dead material may accumulate in bunch-grasses and restrict access to new growth by grazing animals. We found that the presence and heights of residual stems in Lehmann lovegrass (Eragrostis lehmanniana Nees) increased the times between successive bites taken by grazing cows, thus decreasing biting rates when compared to bites taken where these stems were reduced. As new tillers elongated, biting rates increased but remained lower on those plants with the greatest amounts of residual stems. Ingestive behavior of cows may be influenced by distinctive features of the vegetation available at each bite taken. The number of bites cows take on grass plants containing large amounts of residual herbage could influence the average biting rate during a foraging bout. Methods of collecting biting-rate data should account for these influences.