R.M. JONES

CSIRO Division of Tropical Crops and Pastures, 306 Carmody Road, St. Lucia, Qld 4067.

Abstract

Animal and pasture production were compared over seven years (1976–1982) under two systems of pasture management on white clover (Trifolium repens) based pastures on the coastal lowlands of subtropical south-east Queensland. The experiment was superimposed, without re-seeding, on old pastures which had degenerated since sowing in 1964. The treatments were: (a) set-stocked at 2.2 beasts ha^–1 and (b) as for (a) but with an increased stocking rate over summer and with lime application in 1974 (2,000 kg ha^–1) and 1980 (1,000 kg ha^–1).
The application of lime with extra grazing resulted in lower total presentation yields but a higher presentation yield and density of white clover. Soil seed reserves increased from c 1,000 seeds m^–2(1976) to 2,500 (set-stocked) and 6,000 m^–2 (extra stocking and lime) in 1983. From 1977 to 1982 animals on the set-stocked treatment gained 144 kg liveweight head^–1 year^–1 and 317 kg ha^–-1. Animals grazing yearlong on the treatment with lime and extra grazing gained 161 kg head ^–1 year^–1 and the total gain per ha was 479 kg.
One replicate of the experiment was invaded by Vigna parkeri. This invasion is described in an appendix where the potential of this species for moist sites is discussed.