An enperine,nt evaluated the influence of several variables on the coumestrol conte,nt of alfalfa (Medicago sativa) silages. Tvo cultiwrs of atfalfr (Morava md Palava) were each harvested on May, Jrme, and October 2000. The forage was allorved to wilt in the srvath to approximately 300 or 500 g/kg dqy nmfter (DM) content and the,n it was e,nsiled wi&out firthsr Eeahent The number of lactic bacteria“ mol4 and yeast as well as pH and concenhation of lactic acid were indikative of adequate prcsernation Thc majority of the initial content of coumeshol disappeared during 50 days ofensiling, but some was still dctected after 150 days. The cor:meshol concelrtration in silages variedwithboftcttltivaraud maturity ofplantu&ilethere wasno significanteffect offte drymatter content of feed forage. This report shows that wilting in the swath catued remarkable increase in coumeshol content of alfalfr.