Jennifer Fimbel, Agricultural Senior Resource Educator, CCE Dutchess County
One of the most commonly asked question asked by horse and livestock managers is how to prevent weeds in pastures and many of my clientele, for various reasons, are unwilling to use any herbicides on their grazing areas. The simple answer is management; the complex answer is implementing a grazing strategy. Ask any farmer that’s a little longer in the tooth about weed management in pastures and they will tell you to mow the fields 3-4 times throughout the growing season. Ask them when and they’ll respond with, “Mow when there’s nothing else to do”.
Pasture is a crop; like corn, oats, wheat and soybeans and it needs to be treated as a crop. A pasture provides nutrition and forage, as well as enough space to support the livestock grazing on it and the manure they leave behind. Quality pasture management and weed prevention will provide more nutrition for the grazing animals and will improve the surrounding water quality better than poor quality or over grazed pastures. Everyone benefits when pastures are well managed. Pastures act as filter strips to prevent excess nitrates, phosphorous and pathogens from entering water supplies. Managed pasture land will also reduce erosion into waterways by holding the soil in place rather than allowing it to wash away.
Evaluating the amount of pasture needed by an operation is fundamental in preventing overgrazing, for providing ideal nutrition and inhibiting weed development. Pasture size should relate to the pounds of animals (not numbers) expected to be grazing in the field. Enough room should be set aside to allow for rotation of fields. Generally it is recommended (depending on the weather, health and type of the soils and pasture) that 500 – 1000 pounds of grazing animal can be maintained per acre. Pastures lower in quality, on poor soils, overgrazed and uncooperative weather patterns will result in greater acreage needed per pound of grazing animals.
Horses and livestock that are lactating, growing or marketed as grass-fed will need higher quality pastures to provide optimum nutrition (16-20% protein) than those on a maintenance diet. Pleasure horses, for example, need forages that provide only 10-12% protein. Knowing the type of stock and at what stage of growth or maintenance they are in will play a part in pasture planting, rotation and mowing. So it should now make sense that grass-fed marketed livestock will need higher percentage forages, a larger land base to graze (and rotate) and breed selection to finish well on pasture (Heritage and British influenced).
Pastures that are managed with rotation from grazed, to mowed, to rest, will ultimately produce more forage per acre and fewer weeds. Even pastures that have been overgrazed will return to optimum growth if managed properly. Pastures should be scouted for weed development just like any other crop and action taken when it is most economically viable. Mowing pastures during planting time just won’t work, but planning to mow pastures should be set into the regular season just as planting and harvesting is scheduled in to the work schedule. If you are growing a grass hay crop, you know how important pH and fertilization is, a pasture is no different and must be considered when spring and summer applications are made.
Last updated March 5, 2015