http://www.growingresults.com/us/h93 University of Illinois Agriculture from Growing Results en-us Copyright 1999-2010, Data Growth Pty Ltd http://www.growingresults.com/us/h93/a133451433.html Preemergence herbicides are used to control weeds before the weed seeds germinate. If you have not done so already, you Preemergence herbicides are used to control weeds before the weed seeds germinate. If you have not done so already, you <br />From University of Illinois Agriculture Control Weeds Herbicides Horticulture Preemergence Preemergence Herbicides Seeds Weed Control Weed Seeds Weeds http://www.growingresults.com/us/h93/a133451433.html