Abstract
To investigate relationships between foraging height of cattle and vertical distribution of leaf mass in native grasses, mass of foliage, density of leaves (as frequency of occurrence) and proportion of bites by beef steers in individual layers (every 20cm height from the ground) of canopies were measured for Miscanthus sinensis, Sasa palmata, Pleioblastus chino and Calamagrostis arundinacea in June-July (summer) and September (autumn). Vertical distribution of foliage mass and leaf density well described the characteristics of aboveground structure in native grasses in each season. Leaf mass in an individual layer was significantly related to leaf density of the layer (P<0.05) in all grass species, showing the effectiveness of measuring the frequency of occurrence of leaves for estimating leaf mass in native grasses. In both seasons, correlation analysis showed that steers took more bites from layers with higher leaf densities. However, the significant relationship between the proportion of bites and leaf density was relatively low in the early period in autumn. It was suggested that, in autumn, other factors such as quality of foliage affected the foraging height of grazing cattle.
