Catch crops after winter forage grazing a win-win for farmers, environment
Hardy catch crops such as oats are showing major promise for mopping up excess nitrogen after winter grazing and could create a win-win for farmers in terms of their environmental footprint and profitability. Dr Peter Carey, a Lincoln Agritech Field Researcher, is leading a three-year Ministry for Primary Industries (MPI) Sustainable Farming Fund (SFF) research programme, in conjunction with Plant and Food Research, to apply the use of catch crops more widely in winter forage rotations. Dr Carey, who completed a PhD at Lincoln University on the use of catch crops, found that they can reduce nitrate leaching by as much as 40%. This study looks to extend his research and apply it directly to commercial farms in Canterbury and Southland. The project aims to adapt their use to the different soils and climatic conditions of each region. “Catch crop strategies are becoming more important, with the new Action for Healthy Waterways regulations coming into effect in winter, 2021,” Dr Carey said. “These will prevent farmers from leaving paddocks bare for more than a month after winter forage grazing. Fortunately, the research is showing that catch crop strategies can be a profitable avenue. “Nitrate leaching, and nitrogen loss generally, is particularly problematic in winter as non-lactating dairy cows eat large quantities of feed over a fairly short period of time to build up their body conditioning. “Then they deposit large volumes of urine onto bare soil at a time when plant growth is minimal. “Usually, catch crops are sown in autumn between the harvesting of the previous summer crop and a new crop in spring to conserve soil nutrients over the winter but in winter forage rotations, they need to be sown at the end of the grazing period, which is often mid-winter when soil and climate conditions are at […]