Grazed crops can beef up farm returns
Dual-purpose crops are offering grain growers in the southern cropping region an opportunity to significantly boost their returns per hectare and whole-farm profitability.
More than a decade of experiments, simulation studies and on-farm validation across Australia have demonstrated that a wide range of cereal and canola varieties can be successfully grazed and later harvested to produce combined livestock and crop gross margins that exceed those for grain-only crops.
The Grains Research and Development Corporation-funded research has shown that with good management, the introduction of dual-purpose cereal and canola crops can boost returns by up to $100/farm hectare.
CSIRO Agriculture research scientist Dr Susie Sprague, who has been outlining the benefits of dual-purpose crops at GRDC Grains Research Updates in the southern region, says grazed crops also produce other farming system benefits, such as widening of sowing windows, reducing crop height, filling critical feed gaps and spelling of pastures.
Dr Sprague said the higher profits on offer from dual-purpose crops relied on attention to detail with both crop and livestock management.
“The opportunities are significant, but the crop and livestock requirements to capitalise on dual-purpose crops are considerable,” she said.
“Successful early establishment, weed control and withholding requirements, stock planning, management and logistics are not trivial to optimise the whole-farm benefits of the extra forage.”
Dr Sprague said a range of winter and spring cereal and canola varieties can be used for dual purposes, depending on the region and seasonal sowing opportunities.
“Early sowing with a suitable maturity type for the site and sowing date will maximise forage and yield potential.”
Dr Sprague offers the following tips for success with grazed crops:
- If it is your first foray into dual-purpose cropping, get good agronomic advice and plan well ahead
- Select a suitable paddock and be prepared to sow early
- Sow early with the right crop and variety. Recommended are winter wheats in March, long-season spring wheats in mid-April and spring wheat in late April. Sow winter canola types in March and spring hybrid types from mid-April
- Protect early-sown crops from establishment pests and aphids that transmit virus
- Aim for a good plant population for good early biomass production for grazing (150 plants/square metre for wheat and 40 plants/square metre for canola)
- Ensure sufficient nitrogen (N) upfront for good early biomass production (100-150 kilograms/ha for winter wheats and canola, and 50-100kg/ha for spring wheats and canola)
- Don’t graze too early as crops are building root mass and can be checked
- Animal health issues – take precautions for bloat and nitrate poisoning as usual for palatable feed, and don’t fertilise with N close to grazing (apply upfront and post-grazing)
- Stocking rates around 1000 kg/ha liveweight work well, but adjust to the feed on offer. Animals take time to adjust to feeding on canola and do best if grazing periods are longer – avoid frequent change
- Lock-up time is key – Consider both crop growth stage and amount of biomass at lock-up to avoid a yield penalty. Remove stock before growth stage DC30 in wheat and bud elongation in canola. To achieve 4-5 tonne/ha grain yield in cereals, leave 0.5 t dry matter/ha biomass at lock-up. In canola, a 2.5-3 t/ha canola yield requires 1.5 t DM/ha in spring canola and >2.5 t DM/ha in winter canola. If grazing later, ensure grazing does not remove reproductive parts of plants
- Top-dress N after grazing to assist yield recovery – assume wheat needs to see 40kg N/ha for every 1 t/ha of yield and canola 80kg N/ha, and adjust topdressing according to existing N and target yield.
More information on dual-purpose cropping can be found in Dr Sprague’s GRDC Grains Research Update paper
Dr Susie Sprague, CSIRO
Phone 02 6246 5387 / 0466 643227
Sharon Watt, Porter Novelli
Phone 0409 675100
GRDC Project Code CSP00160, CSP00132