Abstract
Changes in dry matter weight and structure of sward were investigated throughout a year on bahiagrass pasture grazed by Holstein heifers under rotational system. Outlines of results obtained are as follows. 1. Standing crop over a year ranged from 1390 to 1890g/m^2. Relative dry matter distribution of organs in standing crop changed in the ranges of 0-1% for ear, 1-15% for leaf, 7-18% for stem, 4-14% for standing dead, 22-36% for stolon and 35-50% for root. Consequently, C/F ratio was high ranging from 5 to 146. 2. As for aboveground parts, most dry matter was concentrated in the stratum of 0-10cm, and stem and standing dead occupied so much amount as more than 66%. This fact was considered as the reason for high canopy extinction coefficient. 3. So far as the regrowth or persistency was not depressed, close grazing to lower aboveground stratum was inferred as one of the pasture managements for higher solar energy utilization in bahiagrass pasture from the reasons as (1) increasing herbage intake by cattle, (2) increasing relative amount of leaf and reducing that of standing dead in aboveground dry matter, and (3) possibly improving canopy extinction coefficient.
