Researcher Offers Pointers On Keeping Pastures Healthy In Hot, Dry Summers

FAYETTEVILLE, ARK.
   Arkansas’ summer has come on hot and dry, presenting challenges for maintaining healthy pastures, said Dirk Philipp, associate professor of animal science and forage researcher for the University of Arkansas System Division of Agriculture.
   The main perennial forages in Arkansas are tall fescue and bermudagrass,” Philipp said.
   “Although rain during spring was plentiful, soil profiles are getting dry,” Philipp said. “Pastures suffer when the weather turns hot and dry following a wet and cool spring that delays growth.”
   Fescue ceases growth during hot conditions, Philipp said. “During those times, fescue should not be mowed or grazed to avoid damage to the sward.”
   If producers decide to cut fescue for hay under these conditions, Philipp said, they should leave at least 4 inches of leaf material on the plants to ensure enough area for photosynthesis.
   Philipp said producers should not keep cattle on summer-dormant fescue pastures to avoid overgrazing, soil compaction and creating openings for weed encroachment.
   “Have a plan in place to move animals somewhere else,” Philipp said, “preferably onto a warm season perennial pasture or pastures of summer annual forages.
   Bermudagrass, because it is a warm-season perennial, will keep growing when it gets hot, Philipp said. But the wet, cool spring this year resulted in little growth going into the hot summer months. Conditions are compounded by a lot of weed pressure, he said.
   When field size is manageable, Philipp said, bushhog fields to cut down on weeds and fertilize the bermudagrass with about 50 to 60 pounds of nitrogen per acre.
   “Once rain resumes, bermudagrass will begin growing again and we’ll have about three months of growing season left,” Philipp said.
   If drought conditions persist, Philipp said, handle bermudagrass with care:
   • Avoid excessive vehicle or animal traffic on pastures;
   • If hay is needed, find a sacrifice pasture for feeding it to cattle to minimize the spread of weed seeds from the hay;
   • Watch out for weed growth later in the season and following years after a drought and tackle weed control proactively to avoid longterm weed encroachment.
   “In the longterm, try to stay proactive by having options available,” Philipp said. Such options can include fields planted in summer annual forages.
   Sorghum-sudangrass and pearl millet are relatively drought resistant, Philipp said. Although they don’t generate their maximum yield of growth during dry conditions, the amount of plant material available may be enough to provide cattle with forage during droughts. ∆