More persistent legumes and grasses for oversown tussock country

Abstract

A grazing trial on oversown tussock country at Tara Hills Research Station, started in 1978 and still continuing, has highlighted short comings of clovers and grasses traditionally used for improvement. In 1984 a wide range of legume and grass germplasm was planted into each of the nine stocking rate/management treatments to identify plant material more persistent than that traditionally used, and investigate specific responses under Extreme (high stocking rate), Optimal (moderate stocking rate and management giving optimum liveweight gain/ha) and Las (low stocking rate) grazing management. After 6 years none of the 12 white clover, 7 alsike and 9 lotus lines tested persisted significantly better than Grasslands Huia white clover (Trifolium repens). Plant survival and spread of Caucasian clover (Trifolium ambiguum) was exceptional. In terms of persistence and spread this legume ranked first out of the 56 germplasm lines under examination. The 15 ryegrasses examined did not persist better than Grasslands Nui ryegrass (Lolium perenne). However, for Optimal management, many ryegrasses performed better than Nui. Cocksfoot(Dactylis glomerata) also performed very well, with Grasslands Wana showing greater persistence under Extreme management than other cocksfoots and ryegrasses. Tall oat grass (Arrhenatherum elatius) was very persistent and like Caucasian clover performed well under all managements. Other grasses tested showed poor persistence, as did the herb sheep's burnet (Sanguisorba minor). Keywords: Arrhenatherum elatius, Dactylis glomerata, grazing management, high country persistence, sustainable improvement, Trifolium ambiguum, tussock grasslands