Q: My neighbor told me he uses gasoline to control weeds. He says it works better and is cheaper than Roundup. What are your thoughts?

A: Gasoline also removes dirt better than soap, but I’ll bet your neighbor doesn’t bathe with it. It is true that gasoline will kill plants faster than Roundup. But gas just burns the leaves; it is not translocated down to the roots, as with Roundup. As for cost, a quart of 18% Roundup costs around $25 and makes ten gallons of sprayable mixture. Gasoline costs about $30 for ten gallons, so it’s more expensive, not to mention the pollution that gasoline causes.

Gas does kill yellowjackets but it also kills the grass around their hole, while water-based insecticides kill the insects just as well and don’t kill grass. If hot air killed weeds and insects, your neighbor could start a business.