While this farmer is windrowing alfalfa, annual forages can also be windrowed and left in the field. Photo by Chabella Guzmanalfalfa-10-9-rows
Harvested feed costs can be one of the largest expenses for cattle producers. Windrow grazing, sometimes called swath grazing, is a management practice that can significantly reduce harvesting and feeding costs. Swathing the crop and leaving the windrows in the field provides several advantages.
Windrow grazing eliminates the costs of baling and hauling bales off the field. It also reduces labor and equipment costs associated with feeding as the cattle graze the crop in the field. Another benefit is that most of the nutrients and organic matter from consumed forage back to the soil where the crop was grown.
In Nebraska, 75-80 percent of seasonal precipitation falls in the six-month period from April through September. Only 20-25 percent of precipitation falls from October through March. This seasonality of precipitation allows for swathing forage crops in early fall and preserving them through the fall and winter with minimal deterioration in quality due to weathering. Cool, dry conditions frequently associated with late fall and winter in Nebraska are favorable for preserving forage in a windrow. Across Nebraska, the average amount of precipitation increases from west to east. Greater average precipitation in eastern Nebraska does increase the risk of windrow deterioration compared to drier conditions in central and western Nebraska.
Windrow grazing of warm-season annual forages such as foxtail millet, sudan grass, and sorghum x sudan grass hybrids can provide an excellent way to harvest these forages when they are at an optimum for quality and efficiently utilize them with minimal waste. Windrow grazing of cool-season annual forages such as spring triticale, oats, and spring barley planted in late summer can provide high-quality feed for late fall and winter grazing as well.
When windrow grazing annual forages, nitrate poisoning is a potential risk. If possible, clip forages prior to swathing and have a nitrate test conducted to see what level of nitrates are present. If nitrates are high, raising the cutter bar higher can help to reduce the nitrate levels in forage placed in the windrow, as nitrates tend to be concentrated in the bottom third of the stem. Annual forages placed in the windrow should also be tested for nitrates prior to grazing. If nitrate levels are too high for grazing safely, the crop can be baled and then ground and mixed with other feeds to dilute the nitrates to a level that is safe for feeding.
For more information on this management practice, see the Nebraska Extension guide Windrow Grazing.
-University of Nebraska–Lincoln