Drought has parched many cool-season grass and legume pastures this summer, and in some regions drought has continued into the fall. The drought has affected pasture productivity, plant health, and livestock stocking rate. Here are some tips and options to consider for management of pastures to provide forage for livestock and to insure long term productivity.
Avoid overgrazing. Do not graze below a 4-inch height. Cool season grasses and legumes become dormant during drought. They will likely regrow upon resumption of normal rainfall if not subject to extra stress. During dormancy, the leaves and stems stop growing but the growing points and crowns are still alive. Overgrazing, that removes all leaves and stems can weaken plants and lead to stand loss and weed invasion. Perennial ryegrass, orchardgrass, and timothy that store energy in stem bases are especially susceptible to combined stress of overgrazing and drought, while alfalfa, smooth brome, quackgrass, and reed canarygrass are more tolerant. Shallow rooted species like Kentucky bluegrass and red clover are also damaged by overgrazing.
Reduce stocking rates. If there is inadequate forage available, livestock should be removed from pastures to a dry lot or sacrifice paddock and fed hay. Hay quality should be assessed to determine if it meets the nutritional needs of the livestock. For hay sampling procedures and recommended analysis see the U of M Extension's page on forage testing and the Hay Analysis Guide from UW Extension.
Avoid the temptation of returning to droughted pastures that have regrown following a small amount of rain. It takes 4-6 inches of water to produce a ton of cool season grass or alfalfa forage. Smaller amounts of rainfall may stimulate regrowth but grazing of tall growing grasses should be delayed until 8-10 inch of regrowth. Shorter growing grass like Kentucky bluegrass and red top can be grazed at a 4-inch height. While grazing regrowth before it reaches these minimum heights may provide forage, it can weaken plants and reduce the long-term productivity of the pasture. For alfalfa-grass or red clover-grass mixtures, grazing before these legumes reach a bud stage will reduce their persistence.
Watch out for weeds. Some weeds may grow when grasses and legumes become dormant, and weeds will be grazed if they are the only available forage. In addition to low nutritive value, some weeds like lambsquarters and pigweed are accumulators of nitrate which can be toxic when consumed in large quantities. Another problem weed in woodlands is white snakeroot, which contains a toxic oil, tremetol.
Provide clean water. Livestock normally obtain some water from consuming moist pasture, and switching to dry hay will necessitate greater water availability especially if air temperatures are warm.
Source: umn.edu
Photo Credit: gettyimages-banksphotos
Categories: Minnesota, Crops, Hay & Forage, Livestock, Weather