1. Q. Something is causing the leaves of my oak tree to curl. I have never seen this before. Is this damaging my tree? What can I do?
A. Leaves of oak trees can be attacked by erophytid (pronounced "Arrow-Fie-Tid") mites which cause a curling reaction. You can spray with diazinon insecticide or just let nature take its course. The curled leaves are still functional and will support tree growth. All leaves will not be affected.
2. Q. We have a spectacular oak tree in our yard that had an infestation of oak galls last year. The gall was a pale parchment-like ball, slightly smaller than a marble, and hollow inside. If it happens again this year, what damage can it do to the tree and is there any way to prevent it?
A. The oak gall which you have described is caused by the cynipid wasp. The immature insect is a legless white larva, the adult a small black wasp. This gall, as is true with most other galls, causes little or no damage to the tree, although heavy infestation may affect its appearance. The only way to prevent galls is to eliminate the insects that cause them. This is a difficult task; there are no known chemical methods of control for the oak gall.
3. Q. I am extremely concerned about the leaves falling from my Live Oak tree. My family and I purchased this house because of the huge oaks located on the property. The trees have been beautiful for several years but are now practically barren of leaves. Does this precious tree have the oak wilt disease? Should it be removed? Some trees have lost more leaves than others.
A. Put away the chainsaw; Nature is just taking Her course. You are not the first individual to be concerned about leaves falling from their Live Oak trees in the spring instead of falling in the fall. I suppose Live Oaks must have a messed up calendar but these silly trees drop leaves every spring instead of fall. Most of the time this loss of leaves is a gradual process but in some years all the leaves fall at once. Since the nomenclature of this oak infers that it is evergreen, people sometimes believe that their precious Live Oak has become a Dead Oak. The sudden leaf drop of Live Oaks is associated with environmental experiences such as a severely cold winter or excessive wetness. Fear not! In a few weeks you will know your Live Oak is well and happy. It will begin to drop tons of beautiful green pollen all over everywhere. You will also know that the tree is going to live longer than you are; your allergies to oak pollen will kill you first!
4. Q: What would you suggest in dealing with suckers or seedlings that emerge under oak trees. Some homeowners thinking of using Roundup herbicide, could this be harmful to the tree or is it even effective in controling an oak sucker or seedling?
A: LEARN TO LOVE THEM because the more you cut the more they multiply. Some homeowners keep them trimmed at a certain height and interplant Asiatic jasemine ground cover -- the ground cover conceals the oak sprout since the foliage is similar. We DO NOT recommend a herbicide application to sprouts since the sprouts are connected directly to the Mother tree and could cause damage. Roundup herbicide will do little more than defoliate the sprouts and could damage the tree to which they are attached. Learn to co-exist; they can become one of the most drought-tolerant ground covers available.
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