Ground Cover Supplement : GC Supplement - Mixed farming
17 MIXED FARMING GROUND COVER CROPS, PASTURE & FODDER David Ferris (centre right) discusses with local growers the minimum yield reduction of BulokeA barley sown over Gatton panic grass as part of the EverCrop focus site at Moora, WA, in 2009. PHOTO: PHIL NICHOLS and Rhodes grass were established. The site near Moora was considered marginal for frequent cropping due to non-wetting soils, low fertility and risk of erosion. In 2009, BulokeA barley was sown across perennial pasture plots. Two nitrogen rates were tested at 50 (district average) and 80kg N/ha. The results, reported in Table 1, indicate minimal yield reduction in a year (2009) that received 380mm of rainfall between April and October. The deep pale sand had little stored soil water. The amount of green feed available in January 2010 in the pasture crop plots was comparable to the permanent pasture treatment. The amount of green feed available six weeks after harvest was 2.6 tonnes of dry matter a hectare for Rhodes grass and 1.3t DM/ha for panic grass. Conditions in 2011 indicate results similar to those achieved in 2009 could occur again. Low rainfall, winter dominant Two locations in the Mallee with winter-dominant annual rainfall ranging from 348mm average annual rainfall at Hopetoun to 339mm at Karoonda have been selected for the low-rainfall pasture-cropping field trials. Five subtropical grass species (Megathyrsus maximum, Panicum coloratum, Rhodes grass, Digitaria smutsii, Setaria incrassate), one temperate grass (Dactylis glomerata spp.) and a new highly winter-dormant lucerne species were sown at Karoonda. Each was sown on 50-centimetre row spacing at the appropriate time during 2010 and 2011, as sole pastures. In autumn 2011, wheat was sown on the inter-row to create pasture-cropping plots and a wheat-only control plot. The pasture species selected were based on 2007--10 trial results from BCG (formerly the Birchip Cropping Group) and CSIRO's Anthony Whitbread. These trials showed that subtropical perennial grasses can be established and persist in the Mallee. These results reported between 1 and 4t/ha of biomass could be produced in response to summer rainfall, 2007--10. The exceptionally wet conditions in the summer of 2010--11 resulted in biomass production of more than 15t/ha at Hopetoun. While the Mallee pasture-cropping trials have only just begun, modelling has shown that pasture cropping has the potential to perform in the Mallee. This modelling found that the biomass and crop return penalties associated with pasture cropping are lower on soils with severe subsoil constraints. Similarly, higher fertiliser rates and greater in-crop rainfall reduced crop yield penalties. The field trials aim to verify these results and refine the pasture cropping management system in low-rainfall regions. □ GRDC Research Code FFI00003 More information: Dr Rick Llewellyn, EverCrop project leader, CSIRO, 08 8303 8502, firstname.lastname@example.org; www.grdc.com.au/FFI00003 Grain & Graze 2 projects on CROPS, PASTURE & FODDER Region Project title Eyre Peninsula Are perennials more profitable than crops in high-risk cropping country? East South Australia Finding solutions to weed, pest and disease issues created by stubble retention East South Australia Extending solutions to weed, pest and disease issues created by stubble retention East South Australia Sowing annual winter and summer crops in the low-rainfall zone East South Australia Sowing plants to utilise seasonal rainfall East South Australia Identifying the effects of stubbles on soil condition Northern Integrating legumes and forages into mixed-farming systems Northern Exploring the benefits of ley pasture systems Northern Improving phosphorus use in legume pastures Northern Victoria Combining paddock feed with containment feeding to fill the autumn feed gap Northern Victoria Testing summer forages for a changing climate Northern Victoria Improving native grasslands while cropping Southern NSW Measuring the benefits and limitations of perennial shrubs in low-rainfall mixed farming Southern NSW Pasture cropping Southern Victoria Increasing legume use in crop rotations within mixed-farming systems Southern Victoria Trialling alternative legumes/break crops in mixed-farming systems For regional Grain & Graze 2 (G&G2) contacts see the back cover EVERCROP AIMS TO PROVIDE DETAILS OF WHERE AND HOW PASTURE CROPPING FITS.
GC Supplement - Soil biology initiative
GC Supplement - Crop protection