Livestock brings high gains
A nine-year study of the impact of livestock on paddock health and farm productivity in a lowrain environment has revealed that grazing generates multiple benefits for mixed enterprises.
The study at Minnipa on South Australia’s Eyre Peninsula demonstrated that many agronomic and financial advantages could be achieved by incorporating livestock into rotation.
Apart from improved gross margins, the benefits of integrating sheep included increased nitrogen cycling and water-use efficiency, reduced weed and pest pressures, and added value to stubble and pastures – without negatively impacting on cereal performance or soil health.
The South Australian Research and Development Institute, a division of Primary Industries and Regions SA, undertook the long-term study, which began in 2008 as part of Grains Research and Development Corporation’s Grain and Graze 3 research investment.
SARDI researcher Jessica Crettenden said the trial, based on a wheat-medic rotation, also tested whether productivity could be improved under a higher input system – higher fertiliser and seeding rates, establishment of improved pasture – compared with a lower input and more traditional system – district practice seed and fertiliser inputs, volunteer pasture – and what effect this had on soil fertility.
Ms Crettenden said some growers on the Eyre Peninsula had been hesitant to increase grazing partly due to the perception that livestock could damage soil health, remove organic matter and induce weed germination.
“But with prices for livestock increasing over the past decade and the valuable nutrition and disease break effect that the pasture phase provides to subsequent cereal crops, interest in the productivity and profitability of medic pasture and livestock systems has increased,” she said.
“The trial showed that over a range of seasons, integrating livestock into a cropping system improved productivity and profitability, particularly in higher input farming systems.”
Ms Crettenden’s GRDC Grains Research Update paper is available online at grdc.com.au/ resources-and-publications/grdc-update-papers.