I head about a new broadleaf herbicide called aminopyralid, by Dow. A relative of clopyralid. It is marketed as "Milestone" in agriculture. It is in the EPA "reduced risk" category. Very low rate of use: 0.03 to 0.1 lb per acre. http://www.weeds.iastate.edu/mgmt/2006/aminopyralid.shtml HOWEVER...aminopyralid is causing problems in England--temporarily banned there. Seems used on pasture land. Then forage havested for silage. Then fed to cows. Then the manure collected, sold and then used on organic gardens. Hard to believe, but it then apparently caused problems--herbicide injury on tomatoes, legumes and sensitive plants. I suppose it will never be registered for use on lawns because the clippings would retain herbicidal activity in a composted situation.