Winter Pasture & Herbicide Seminar Weed control, soil fertility, and cool season forages UT Agriculture Extension Agents Brian White and Becky Muller led a seminar on Pastures, Winter Weed Control, and Cool Season Forages at Agricenter International in Memphis, TN on September 14, 2010. The agenda covered herbicides for weed control, soil fertility, and cool season forages. John Booth from DuPont discussed Pastora, DuPont’s new herbicide that can be used in pasture and forage programs. Pastora is a combination of two previously-used herbicides, Nicosulfuron and Metsulfuron Methyl. It was developed especially for Bermuda grass pastures and hay forage as a replacement for MSMA Herbicide. The ideal time to apply Pastora is February and March for winter grasses, and after the first cutting to control Johnson grass. Pastora can be combined with diluted nitrogen (N20a) in the same application. Brian White discussed how and when to spray herbicides, and when to mow, for the best winter pastures. He described the most commonly used, approved chemicals and the cautions that must be taken with their use. Read the label for this information! White recalled his own experience: he had been spraying chemicals one day and hopped off the tractor to clear a clogged nozzle. He wasn’t wearing proper protective gear, and as a result of contact with the chemical, was hospitalized for three days. Brian emphasized the importance of timing when spraying; even the time of day will affect drift and penetration. He gave the example of a person who was using 2-4D in a hand sprayer to kill weeds around his mailbox. He sprayed it very late in the day when there was a temperature inversion fog, and accidently killed the cotton in his neighbor's field across the road. UT annually publishes a weed control manual, with a reference chart of chemicals to weeds, and compatibility of mixing chemicals. The most commonly used herbicides labeled for organic operations are clove and citric acid. Care must be taken when applying them since they are caustic and not selective. Herbicide and pesticide certification cards are renewed every three years in Tennessee, and must be renewed again in September 2011. Winter Forages. Fescue is best planted in late summer and fertilized after rain in the fall. Fescue is high in protein and has very good TDN (total digestible nutrients) until late December. Fescue should not be fed to pregnant and lactating mares. The endophyte that grows on Fescue is very helpful to the plant, but can cause mares to miscarry and their milk to dry up. There are two new varieties of Fescue with a non-toxic endophyte. Annual rye, ryegrass, and wheat are very cold tolerant. Rye can be over-seeded on Bermuda pastures, and ryegrass is most productive in early spring. For more information about winter forages in the mid-south, visit: www.forages.tn.edu.