Select paddocks
Select paddocks early, and consider:
- Soil type - which can impact nutrient and sediment loss and animal welfare. Lighter, well-drained soils are generally the most suitable for intensive winter grazing but can present a greater risk of nitrogen (N) leaching. Heavier soils are typically more prone to structural damage (pugging and compaction) and sediment and phosphorus (P) loss.
- Critical source areas - identify critical source areas (such as swales and gullies that can channel overland flow directly to waterways), and leave an ungrazed, uncropped buffer zone within and around these areas, to slow overland flow and trap suspended sediments and nutrients.
- Slope - as increasing slope increases the risk of sediment and P loss. Consider how the paddock will be grazed and the class of stock grazing in relation to the slope.
- Stock type - consider the stock class best suited to the environment. Some paddocks may be suitable for younger or lighter animals, for example.
- Animal welfare - where possible, plant crops in paddocks with access to shelter. Alternatively, allow a feed buffer in your budget to account for feeding extra during adverse winter weather events.
Best practice fertiliser management
- Test soil using the Brassica Test at least six, but ideally 12 months before sowing. This allows time to adjust soil pH and correct nutrient levels with a suitable base fertiliser if necessary. The test includes a measure of the amount of available N in the top 150 millimetres (mm) of soil, which is used to calculate the amount of N required to meet crop demand.
- Use a starter fertiliser at sowing. Drill with the seed (in a separate box) or broadcast then incorporate it into the soil just before sowing. Putting N and P close to the seed gets the crop off to a good start and helps to optimise yield.
- Once the crop is growing vigorously, test herbage to check the nutritional status and apply post-emergence N for:
- Fodder beet just before or at canopy closure. Review soil test results to check reserves of available N. If high - >200 kg of N per hectare (ha) - postemergence N will likely not be required, as long as N has been applied in the starter fertiliser.
- Brassicas at six and 12 weeks after sowing. If very high amounts - >100kg N/ha - are required, split the applications. As a rule, the first application should go on at canopy closure.
Grazing management
- Record what you will be doing and where. This can be shared with staff so everyone has the same understanding of how grazing will be managed.
- Graze paddocks strategically. On sloping paddocks, fence across the slope and start grazing at the top of the slope, so the crop acts as a filter. If there is a waterway in the paddock, start grazing at the far end of the paddock.
- Measure feed accurately to ensure the total quantity grown will meet winter animal requirements and allow extra feed for poor weather events.
- Long, narrow breaks can help to utilise the crop more efficiently.
- Back fencing off grazed breaks helps to minimise pugging and runoff risk.
- Place portable troughs and supplementary feed in drier parts of the paddock, well away from waterways or critical source areas.
- Exclude stock from critical source areas, ideally keeping them out for the duration of the winter period.
- Exclude stock from waterways with an ungrazed buffer zone of ideally at least five metres (m), but more on sloping ground. Check if your regional council has rules on buffer zones and winter grazing.
For more information, contact your local Farm Source TSR or Ballance Nutrient specialist.
Article supplied by Ballance Agri-Nutrients.