02100nam a2200193 a 450000100080000000500110000800800410001910000160006024500550007626000350013130000100016649000290017652016030020565000130180865000250182170000190184670000250186570000160189012455272003-07-01       2001    bl uuuu     u0uu1 u    #d1 aSHAW, D. R.  aForage species tolerande to imazapyr and imazapic.  aMississippi State: MAFESc2001  a13 p.  a(MAFES. Bulletin, 1106).  aWeed control with imazapyr (Arsenal), imazapic (Plateau), and hexazinone (Velpar) was better with summer than with spring applications, but dry weather was a factor in the spring application performance. Imazapic provided less controle of horseweed and common cocklebur than imazapyr and hexazinone. Populations, heights, and dry weights of Austrian winterpea, annual ryegrass, hairy vetch, crimson clover, and white clover were higher following spring herbicide application as compared with summer application. Late-season vields were as high with imazapyr treatments as they were with the untreated check for all species in both the spring and summer applications. Yields of annual ryegrass, crimison clover, and white clover were lower following imazapic than following imazapyr with spring applications. There were no differences in yield of Austrian winterpea and hairy vetch across treatments following the summer applications. There were no reductions in the population or height of the spring-planted species (partridge pea, American jointvetch, Kobe lespedeza, and serecia lespedeza) across treatments, except for the spring 1989 application when the crops were planted 2 days after herbicide apllication. In this test, populations and heights in all treatments were less than the check, 0.125 lb/A of imazapyr, or 0.125 lb/A of imazapic. The latter had the highest populations and heights compared with all other treatments except the untreated check. Field tests have therefore shown that there is tolerance of these species to imazapyr and imazapic, but application timing is important.  aForragem  aProdução Agrícola1 aWATKINS, R. M.1 aGARRIS JUNIOR, S. B.1 aCOLE, A. W.