Based on the photo we have sent, what is wrong with our oak tree? Is there something that we should be doing to ensure its health? — Mitchell and Anna Jones, Libertyville From your photo, I can see ...

Q: Everything under one of my large potted plants on the patio is turning black. What isn’t black is sticky. What is wrong with this plant? A: From the pictures you sent me, we know that the black ...

Many people have a potted citrus plant or two that they keep indoors during the winter and move outdoors for the summer. It may be one of those dwarf trees that produce full-sized fruit. Or it could ...

Q: I’ve got a previously healthy stand of Mexican fence post cactus that has been infested with a white scale pest of some kind. Can you tell me what it is — and how I might get rid of it? A:Your ...