Long-term research shows grazing grain crops with livestock can improve whole farm profits for Western Australian grain growers—as long as they implement certain management measures.
“If these farming system changes are not implemented along with crop grazing, whole farm profits are likely to remain unchanged, or even decline, if too much crop income is sacrificed chasing additional livestock income,” said Philip Barrett-Lennard, Grain and Graze project leader, and agVivo consultant.
Mr Barrett-Lennard helped conduct a series of crop grazing trials across the WA grainbelt between 2010 and 2016 as part of the Grain & Graze 2 and 3 projects, which are Grains Research and Development Corporation (GRDC) investments.
“Over the last decade, mixed farmers in WA have increasingly embraced crop grazing as a tool to improve livestock productivity and whole farm profitability,” he said.
“The WA Grain & Graze research has helped to quantify the impact that crop grazing in WA has on whole farm profits as a result of changes to grain yield and quality, crop flowering date, frost damage, and livestock productivity.”
Mr Barrett-Lennard said the WA research had shown improved profitability was likely when there was a higher stocking rate across the farm, some crops were early sown, crops were grazed with ‘highly responsive’ livestock such as pregnant ewes, crop yield penalties were minimised by not over-grazing, and more crop area was sown across the farm.
“When crop grazing is managed well, grain yield reductions of only 0-10 per cent should be expected,” he said.
“To optimise farm profit, the aim should be to more than offset any such yield loss with an increase in livestock enterprise returns.”
Mr Barrett-Lennard said getting crops in the ground early could significantly boost the amount of biomass available for grazing in late autumn and early winter, when there was typically a feed shortage in WA.
He recommended grazing started when the crop was anchored—typically three to four weeks after sowing—at about the three-leaf stage.
“Findings from Grain & Grain analysis indicate grazing crops lightly, by ‘clipping’ the top 5 cm of the plant, early in the growing season, can lead to smaller yield reductions than heavier and later grazing,” Mr Barrett-Lennard said.
“Grazing down to ground level is not recommended.”
Mr Barrett-Lennard said initial thinking under the WA Grain & Graze projects was that a high stocking rate for a short period was preferable to avoid overgrazing and to speed up crop recovery.
“However, we have found over time that due to low stock numbers and large paddock sizes, implementing more intensive grazing management on crops in WA is often not practical,” he said.
“The alternative of a lower stocking rate—as low as one to two ewes per hectare—for a longer period (up to six weeks) has proved successful in most cases.”
Mr Barrett-Lennard stressed the importance of growers adhering to any grazing withholding periods for pre and post-emergent herbicides, seed treatments, insecticides, and fungicides.
More information about successful crop grazing is outlined by Mr Barrett-Lennard in a new GRDC ‘Know More’ video Crop grazing tips for WA mixed growers, available at: https://grdc.com.au/KnowMore-CropGrazing.