Q. My neighbor pruned his live oak tree but did not paint the wounds. His argument was that the temperature was over 90 degrees so the sap beetle carriers and the oak wilt fungus would not be active. Is that a legitimate excuse not to paint the wounds?
A. Technically, the trees are considered safe if the temperatures are over 90 degrees, but the best thing is to paint all the wounds. It is a horticultural and a social disaster when oak wilt spreads through a neighborhood killing the oak trees. And, in fact, in some communities, including San Antonio, it does not matter what the temperature is, the pruning cuts on oaks must be painted.