By Sarah Sommerfeld PAg, Agri-Environmental Specialist, Outlook
Across the industry, many livestock producers have adopted some type of extensive winter feeding system on their operation. Extensive winter feeding systems can reduce an operation’s cost of production related to yardage, feeding and manure spreading. When used, bale grazing, swath grazing, feeding with a bale processor or any combination of these, can result in animals being out on the land, distributing nutrients and manure.
Careful site selection and appropriate site management are critical in ensuring that the benefits of the extensive feeding system are captured, while also ensuring that environmental risks are minimized. The greatest environmental risk associated with a wintering site relates to the potential impact on surface and ground water quality. Nutrients, pathogens and sediments associated with the wintering site have the potential to move into water sources, impacting the water quality and suitability for use.
When choosing a site for extensive wintering, there are several factors to consider.
Slope is the natural rise or gradient of the land. Slope impacts nutrient run-off, overland water flow and bank erosion. A site with less than two per cent slope is recommended. Limiting runoff potential from a site reduces nutrient contamination of waterways and streambank erosion. Runoff can be managed by maintaining vegetative cover or by installing water control structures such as catch basins, berms, or ditches.
Select a site with good ground cover. Ground cover reduces the amount of nutrient run-off from the site and limits contaminants from entering waterways. Perennial forage stands in good condition or annual cropland with stubble and chaff remaining are options that provide the least risk. The depth to groundwater should also be known. The risk of contaminating ground water sources increases on sites with shallow water tables. Choose a site where the depth to groundwater is at least 30 meters (100 feet) from the surface.
Management of the site after the winter feeding season is also important. A build-up of manure or feed residues may need to be addressed before the growing season starts. Follow-up management may include harrowing to spread manure or feed residue, or tillage operations on annual cropland prior to seeding.
Locating an extensive wintering site that is safe, secure and limits the negative impact on the surrounding environment requires consideration of many features. Take the time to know the limitations of your potential site and plan accordingly. For further information, or to speak with a specialist, contact the Agriculture Knowledge Centre at 1-866-457-2377.