Vinegar isn't used to control roadside weeds

I've got some money on this one, Since You Asked guys, so you better come through for me. I made a little wager with a friend — a six-pack of beer to be precise — because I insisted that Jackson County controls the weeds on the side of the road with vinegar — yes, vinegar. I looked it up online, and sure enough a strong vinegar solution is an effective herbicide. My friend said I must be guzzling too much wine vinegar. He insists I can't be right. So, remember guys, I've been a fan of your column for years. Don't disappoint me. Who is right?

— Jim D., White City

We would dearly love to make you a happy man, Jim. But, to paraphrase a line from George Washington, "We cannot tell a lie."

We can report that you are right about one thing: A vinegar solution can be an effective herbicide. However, agricultural-grade vinegar solutions are much more acidic than the stuff in your cupboard. In fact, when handling it, you should wear gloves and a mask because the solution can be quite irritating to your skin, eyes, throat and lungs.

However, the King of the Roads himself, John Vial, head of the roads department for the county, made it clear: "We don't use a vinegar solution," he said.

The county uses a variety of approved chemicals and programs to treat the areas near roadways. A pre-emergent spray program involves a chemical that helps prevent weeds from sprouting in the first place. About 1,400 man hours are involved in spraying 1,700 acres annually at a cost of $184,000.

If the pre-emergent doesn't kill them, then spot spraying nails many other weeds that pop up. That program involves 1,250 man hours and covers 950 acres, costing $111,300.

Particularly noxious weeds, such as puncture vines, require an even more aggressive effort on the part of road crews. Some 790 acres are sprayed and require 1,300 man hours at a cost of $118,000.

Vial said the county spends so much to vigorously control weeds for a variety of reasons: to make sure road signs aren't blocked by grasses and to limit fire hazards, among them.

Another important consideration is that weeds that grow on the side of the road help retain water, which can undermine the roadway itself.

The gravel areas on the side of roads are designed to help water flow away from the road surface.

"A shoulder filled with vegetation is hard on your road," Vial said.

To summarize, Jim, you owe your friend a six-pack.

Send questions to "Since You Asked," Mail Tribune Newsroom, P.O. Box 1108, Medford, OR 97501; by fax to 541-776-4376; or by email to We're sorry, but the volume of questions received prevents us from answering all of them.

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