INSECT, PLANT DISEASE, & WEED SCIENCE NEWS [No. 89-06] [April 25, 1989]

In This Issue: Leafy Spurge Control Pasture spraying and Grazing Restrictions Weather Your Herbicide Works or Not Leafy Spurge Control Leafy spurge, an aggressive plant, continues to spread in Nebraska, greatly reducing the carrying capacity of grazing land. The weed is more common across the northern portions of the state but can be found elsewhere. Leafy spurge is a perennial and reproduces from seed as well as from buds on its deep, extensive root system. It reduces forage production and cattle avoid grazing infested areas because it is an irritant and mildly poisonous. Because of the unusually warm temperatures this spring, the development of the plant is about two weeks ahead of schedule. Pasture Spraying and Grazing Restrictions Grazing restrictions on sprayed pastures vary with the herbicide and the type of livestock. with 2,4-D, do not graze animals on treated areas for 7 days after treatment. Dairy animals should not graze· treated areas for 14 days after treatment. Remove meat animals from treated areas 7 days prior to slaughter. Withdrawal is not needed if 14 days have elapsed since treatment. Do not cut treated grass for hay within 30 days of treatment. Weather Your Herbicide Works or Not The dry spring we\u27ve had so far may adversely affect some early preplant treatments. All pre emergence applications require rainfall to activate them, including early preplant treatments. In some situations, very little or no rainfall has occurred since these treatments were applied. This doesn\u27t present a problem as long as the weeds haven\u27t germinated. However, in some situations there may be enough moisture present to cause weeds to come on