Farmer-managed, on-farm demonstration of the impact of pasture technology on crop and livestock production
1SA Research & Development Institute. Turretfield Research Centre, Rosedale SA 5350
2SA Department of Primary Industries. Clare SA 5453
3Hart via Clare, SA 5453
The low rate of adoption of available pasture technology is a major constraint to improving whole-farm profitability. One approach to accelerating adoption is to establish demonstrations under realistic farm management conditions. This paper outlines an ongoing demonstration of the impact of pasture manipulation on crop and animal production in a ley farming system.
The demonstration is located on the property of Mr. Kevin Jaeschke (aar 440mm. alkaline clay loam pH 7.8) and involves two unreplicated pasture management systems:
Conventional; continuously grazed, spraytopped (Roundup) in spring Innovative; deferred grazing, grass selective herbicide (Fusilade) in winter
The two systems were established on adjacent areas of 1.6 ha, fenced and watered, and stocked with 13 wethers. The pasture treatments were imposed in 1991, the area was cropped to durum wheat in 1992, and the pasture allowed to regenerate in 1993.
The two systems had a marked effect on pasture, animal and crop production (Table 1 ).
Table 1. Effect of pasture system on pasture. animal and crop production.
The major benefit of the 'innovative' pasture system was higher grain yield due partly to the control of the cereal root disease. Take-all (Gaeumannomvces graminis). Other factors contributing to the difference in grain yield may have included soil nitrate, soil water, and weed density however, the isolation of these separate effects was not attempted in this on-farm demonstration. A secondary benefit was improved nutrition (liveweight) of sheep over summer. The results demonstrate the large benefits that can flow from increased pasture management inputs to subsequent cereal crops, and potentially, through higher seed reserves, to subsequent regenerating pastures. The regenerating pasture and livestock performance will be monitored in 1993 and featured at the Hart Field Day.