Mineral composition of autumnwinter stockpiled limpograss

Three cultivars of limpograss [Hemarthria altissima (Poir.) Stapf et C. E. Hubb.], 'Redalta', 'Greenalta', and 'Bigalta', were evaluated for use as autumn-winter stockpiled forage. Previous research had shown these cultivars to have a good yield potential in the cooler autumn-winter period, and had suggested that 'Bigalta' had potential for stockpiled-use because of its higher in vitro organic matter digestion. Changes in mineral composition with maturity of autumn-winter stockpiled limpograss were investigated. The grasses were allowed to regrow from the beginning of August and mineral composition of available forage was determined at various intervals during the autumn-winter period. K and P contents decreased to levels below those recommended by the National Research Council for ruminants. Ca content frequently fell below the recommended level for lactating beef cows. Mg content did not fall below the recommended minimum. The data indicate that mineral supplementation would be required for cattle feeding on 2 - 3-month old limpograss.