By Dr. Liliane Silva, Forages Extension Specialist, Clemson University
In the southeast region, most livestock forage systems are based on use of perennial grasses. Some of these forages are warm-season species and remain dormant during the cooler months of the year. Due to our weather conditions, we are still able to grow cool-season forages to extend the grazing season and decrease our reliance on hay feeding in SC. Cool-season forages have the potential to produce high quality feed under low costs allowing for higher weight gain and improving profitability of livestock-forages systems, but it is essential that proper management is used on these annual forages.
Management starts prior establishment
- Soil testing ahead of time is crucial to apply lime and nutrients based on soil report
- Use of certified, high-quality seeds improves establishment and decrease chances of introduction of weeds in the area
- Proper land preparation is crucial either if you are using clean seedbed (Fig. 1) or interseeding (or overseeding, both terms are used) a perennial pasture with cool-season forages. In the later, mowing or grazing down to 2” will help to remove the excessive forage mass and improve the chances of proper seed-soil contact
- Calibrate your planting equipment correctly and use proper seed depth
- At establishment, plan your fertilizer applications for the range of forage production you are planning on getting. For nitrogen (N) fertilizer, it is a good practice to split the total rate of the season in 2-3 applications to be conducted after grazing events on a specific area, just to make sure that the plant will be able to optimize the use of N while also decreasing issues with leaching and runoff.
Grazing management
Making sure that the forages are given enough time to grow and establish is crucial ahead of starting grazing. If grazed too early, plants will not have enough energy stored and their root systems may not be well developed yet. In both cases, after removal of the leaves, plants will struggle to regrow which can slow down the establishment and compromise the persistence of those plants in the stand. The time that you will be able to start grazing your pastures will depend on the varieties used, planting date, location of farm and fertility applied. Then, generally, most producers manage their cool-season pastures under rotational or strip grazing to optimize the use and quality of the forage. In terms of recommendations, for small grains, for example, a general rule of thumb is to start grazing around 10-12” and end grazing around 4-5” stubble height. The target ‘begin’ and ‘end’ grazing stubble heights will depend on the forage or mixtures you are using on your pastures. It is a good practice to always estimate the forage mass you have available on your pasture and adjust the stocking rate needed to optimize use and the regrowth of forages. When we leave more behind, we may have a more rapid regrowth. However, once most cool-season forages are annual species, we can often manage them under more intensive grazing strategies because they will not persist for the next season. One exception may be when we are using legumes because it is important to remember that they require a proper balance between frequency and intensity of grazing to give the legumes better chances to recover and persist in the pasture overtime. In legume-grasses mixtures, we will need to adequate the management we will be using to avoid shading and competition for nutrients, while allowing the legume to establish well to be able to fix N and incorporate it back into the forage system. It is also important to remember that when we expose animals to legumes for the first time, we need to make sure to turn them in the area gradually overtime, do not starve animals and always let them have access to hay or grass to balance out the consumption while grazing legumes to avoid issues with bloat. Under adequate management, cool-season forages are a good alternative to extend the grazing season with high quality forages while decreasing use of hay. For more information contact your local Extension agent (Livestock and Forages team information available at https://www.clemson.edu/extension/livestock/team.html).