By Jim Wright, Rangeland Management Specialist
Natural Resources Conservation Service
It looked like relief from the drought conditions of 2011 when the winter and spring precipitation brought not only needed moisture but also hope for the summer and a bumper crop of cool-season plants. Most of these plants—annual bromes or cheatgrass, western wheatgrass, and smooth brome—were able to germinate or grow rapidly because of the early warmer-than-normal conditions in the early spring. The warm-season species also start growing up to six weeks early in most places of southwest Kansas before returning dry conditions put them back into dormancy.
Warm-season grasses such as blue grama, sideoats grama, and buffalograss suffered losses because of the extended drought and forced dormancy due to dry conditions and prolonged high temperatures. Many of the dead root crowns can be directly related to drought damage. The primary method of recovery with losses of this type is the re-generation of plants through germination and survival of seedlings when appropriate moisture conditions return.
The large number of cool-season plants makes survival of seedlings difficult because of their high level of competition for water and nutrients.
What can be done? The most effective manner of controlling cool-season species is through managed grazing of livestock during the normal dormant season of the warm-season species.
What do we mean by managed grazing? Putting livestock where they need to be when they need to be there and moving them as the vegetation dictates.
An effective method of controlling flushes of cheatgrass and expansion of other cool-season species such as western wheatgrass and smooth brome is to separate an affected area into smaller fields (3 to 8) and move the livestock through them at a rate where they are back in a given field about 21 days after they were removed. Following this rotation will help keep the cool-season species from setting seed and expanding any further into the upland areas while providing very good nutrition and gaining benefit from forage not otherwise utilized. Using this type of rotation several years in a row shows the incidence of cheatgrass reduced and helps control the expansion of other cool-season species.
By providing a means of control on the cool-season species, warm-season species do not have as much competition for available moisture and nutrients, giving them a better chance of survival and recovery. Additional rest during the warm-season growth period (May 1 to November 1) will also help with the drought recovery of these important forage plants.
If you are interested in more information on controlling cool-season species, managed grazing, or drought recovery, please contact or visit your local Natural Resources Conservation Service (NRCS) office for assistance.
For more information about NRCS programs, visit the Kansas NRCS Web site at www.ks.nrcs.usda.gov. Follow us on Twitter @NRCS_Kansas. USDA is an equal opportunity provider and employer.