Q. I was listening to your radio show last week when you had a question from a listener about whether ball moss was a threat to his oak trees or not. I heard you say that it was not a parasite or a threat to the trees but did not understand the evidence. Please repeat it.
A. The ball moss just lives on the tree. It gathers its moisture and nutrients from the air. The environment in the interior of the tree is ideal because the humidity is relatively high, and the air movement is reduced. I find the most convincing evidence that the ball moss is not removing water and nutrients from the trees because the ball moss will even survive on utility lines and fence lines. The City of Pleasanton is one of the best places to see this.
Q. Our lawn was infested with grubs last summer. When should we apply the insecticide to prevent lawn damage this year?
A. Apply the grub control about June 1 when the June bugs are actively flying in the evening around your porch lights. Follow the label instructions. The same soil insecticide will also control chinch bugs.
Q. Despite the freeze issues, our peach trees have a surprisingly good crop. Do we need to fertilize them again this spring to help the trees finish the crop of large blemish-free fruit?
A. No, spray an insecticide and fungicide each week to protect the fruit from pests and disease. Only fertilize again in the fall if the trees do not produce 18 inches of new stems after this summers crop is harvested. Applying fertilizer now with a crop on the tree will interfere with its development.
Q. My snapdragons are showing rust like symptoms on the foliage and have quit blooming. What should I treat them with?
A. Rust fungus is the usual way that snapdragons end their bloom and life in the early summer. There is not any recommended treatment except to remove them from the garden. Replace the snapdragons with zinnias or vinca for the summer.
Q. Last year our tomatoes were wiped out by mites. What is the recommended treatment to control the mites?
A. Some gardeners can slow down the development of spider mites with a preventative spray of 2 tablespoons of seaweed extract applied to the underside of the leaves once/week.