Management of introduced cool-season perennial pastures during and after drought
Although Kansas has received some rain recently, it’s still dry in the western third of Kansas. Drought is challenging and unfortunately all-too-common in western Kansas. Proper grazing management is critical for maintaining a high-quality pasture; particularly during and immediately following a drought. The following management tips are important for maintaining introduced cool-season perennial pasture or hay fields:
Minimize overgrazing: Grass during a drought is under stress, and overgrazing the pasture can weaken the plants by reducing root carbohydrate reserves, shorten rooting depth, and lengthen the recovery period, even after the drought ends. Therefore, it’s wise not to overgraze. One way to avoid overgrazing is by using a rotational grazing practice. Also, the stocking rate should be reduced to 65-75% of normal during the drought and for the first year or so after a drought. This will help forage plants recover from drought stress and regrow faster next spring.
Use sacrifice paddock(s): One of the ways to minimize severe drought damage to pasture plants is to set aside a sacrifice paddock where hay is fed, rather than graze every pasture. The sacrifice paddock should be the old, low yielding/quality pasture that needs to be renovated in the future. Or better yet, put cattle in pens and bring them feed.
Watch U.S. drought outlook: The long-term weather forecast can change, but you might get an idea about current drought condition and short/long term drought impact in the U.S. from the following website: http://droughtmonitor.unl.edu/. By doing this, you can make plans based on either continued drought conditions or an end to the drought.
Apply fertilizer: Right after a good, soaking rain, applying nitrogen fertilizer (25-30 lbs N per acre) in the fall can help the drought-stressed cool-season pasture recover faster and survive the harsh winter by storing more root reserves. If the soil of drought-stressed hay and pasture is low in phosphorus and potassium, it’s important to fertilize these nutrients as well to have better winter survival. Also, adjusting phosphorus would help lower the risk of grass tetany by increasing magnesium uptake in the spring.
Plant cool-season annual forages to extend grazing season: Drought-stressed cool-season pastures typically will not produce enough forage during the growing season to support normal grazing production. If soil moisture and land area is available, some producers could plant cool-season annuals, such as forage brassicas (turnip, forage rape, or kale) and small grains (rye, wheat, or oats), to extend grazing season. Although forage brassicas are not drought tolerant crop, they can be planted in late summer.
Control stubble height: To restore healthy forage stands, it is important not to graze or harvest drought-stressed forage plants too short in the fall. It is desirable to leave about 6 inches of stubble before entering winter, which will be helpful to catch snow for moisture replenishment and for regrowth in early spring.
Doo-Hong Min, Southwest Area Crops and Soils Specialist
John Holman, Cropping Systems Agronomist, Southwest Research-Extension Center
Walt Fick, Rangeland and Pasture Management Specialist