Mulberry weed is tough to defeat

Q: I have been invaded by mulberry weed. Any advice to get rid of it forever? Jerry Hochman, email

A: This is a plant to which the phrase "get rid of it forever" does not apply. It sets seed only a few weeks after it sprouts and then scatters them prolifically. Once seeds hit the soil, they can remain viable for years, waiting for favorable weather to germinate. I think the best strategy is to be persistent. Pull and dispose of the weed whenever you see it. Spray patches of the weed with weed killer. Consider applying a weed preventer that contains dithiopyr (Dimension, etc) twice each year, in mid-March and again in late May.

Q: How often can one apply lime to a lawn to raise the pH? Drew Bowers, email

A: You can apply lime to a lawn, if needed, a couple of times a year. Since it can take several months for lime to change soil pH, I recommend you have a soil test done every two years. Having your soil tested by a university laboratory (georgiasoiltest.com) is cheap and easy to accomplish. A soil test report will tell you not only the soil pH numbers but also the levels of other nutrients that might be lacking. The acidity of the soil directly affects how fertilizer is absorbed, so you don't waste money.

Q: Is there is a device that could carry an electric charge and which could be clipped to small invasive trees and, with the press of a button, cause that nuisance plant enough harm that it would die quickly? They say men have walked on the moon, this seems such a small thing in comparison. Mark Mauldin, email

A: As a guy who loves fireworks, I would love to see something like this demonstrated. My guess is there would be a small explosion with clouds of steam and a shower of sparks. What a sight! But such a device doesn't make sense when it's easy to kill small- to medium-size nuisance trees in your landscape without pyrotechnics. Just use a small hatchet to firmly chop into the tree trunk at several places around its circumference. Then spray or paint glyphosate (Roundup, etc) into the wounds. The chemical is carried by the tree's vascular system up to the top and down to the roots, and it will die in short order.

Q: I recently read an article about putting owl nest boxes in the backyard. Will having owls in my yard scare away the bluebirds that regularly nest there? David McAlpin, Warner Robins

A: I'm guessing the article described building and installing nest boxes for our native screech owls. It's an unavoidable fact that owls do eat small birds, usually at dawn when the birds are first moving around and the owl feels comfortable flying about. That said, screech owls also eat mice, voles, toads, and insects. Despite the uncomfortable facts, I have an owl nest box in my landscape as well as a bird feeder. Somehow owls and songbirds have coexisted through the ages so I hope I'm not favoring one over the other in my decisions.