THE VALUE OF REGRASSING WITH IMPROVED PASTURE CULTIVARS IN WAIKATO

Abstract

The pasture and animal productivity of established high producing pastures in the Waikato has been compared with newly sown pastures based on recently released herbage cultivars. The established pastures were a mixture of Nui perennial ryegrass, Paspalum dilatatum and Htiia white clover. The new cultivars tested were Ellett perennial ryegrass, Wana cocksfoot and Roa tall fescue, each sown with Pitau white clover. The main advantages of the new pastures containing Ellett were in increased autumn and winter herbage production, higher stock carrying capacity and lower hay requirements. The Ellett pastures had higher ryegrass content and lower weed levels than the older pastures. Wana cocksfoot when grown with Ellett ryegrass increased in content over the experimental period, especially under less intense grazing pressure although some frost damage was evident in winter wi!h a possible lowering of herbage nutritive value of the mixture. Tall fescue pastures only showed occasional merit in summer-autumn periods under the less intensive grazing regime. Keywords: established pastures, Nui ryegrass, Ellett ryegrass, Wana cocksfoot, Paspalum dilatatum, Huia white clover, Pitau white clover, Roa tall fescue, steer liveweight gains, seasonal herbage yields, herbage yields, herbage botanical composition.