Q: You always recommend the popular brand name weed killers but these are expensive to use. Vinegar will kill weeds and is only $2.00 a gallon. Is there some reason it should not be used?

A: I sometimes recommend brand name weed killers over vinegar for two reasons. Many herbicides that control broadleafed weeds are selective. They kill the weed but do not harm the surrounding grass. Vinegar is not selective. Glyphosate, the ingredient in Roundup and other products, is translocated from the leaves to the roots of a weed. Vinegar is not translocated. It is true that 5% vinegar (acetic acid) will kill young, tender weeds but it does little damage to established weeds. In government research, only 20% acetic acid gave good weed control results. However, until recently, no company had taken the time to have a 20% acetic acid weed killer legally registered for homeowners. Weed Pharm is now available online at Pharm Solutions Inc. Remember, acetic acid is dangerously corrosive; it will burn your skin readily. Read and follow the label directions exactly.