Why are we are seeing different shades of green on Live Oak Trees? Some trees have a silverish tone, others have a bronzeish appearance to the leaves. This is due to an infestation of mites feeding on the foliage that have been present for months. Mites have a mouth part like a mosquito that they insert into the leaf to feed by pulling out the chlorophyll, which gives the leaf its green color.
Mites are still present and continue to feed here in the North Texas and Dallas/Ft. Worth area.
They are a very debilitating insect whose sole purpose in life is to feed and reproduce. Their feeding causes low vigor and vitality in the trees, making them more susceptible to other infections and diseases.
Cold spells seem to have no effect on these insects. It appears as though the cold just makes them less active and as the day warms they begin feeding.
I highly recommend treating for these critters immediately. The longer they are present, the more long term damage that is done to the tree. Sometimes additional treatments are required, but it is well worth it in relation to the alternative.