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Oak Tree Caterpillars and Powdery Mildew


Oak Tree Caterpillars

Be on the look-out for oak tree caterpillars in your oak trees. They cluster together in large groups feeding on the leaves of your trees or you may notice poop under your tree (on your patio or walk.) They can be killed with Thuricide sprayed onto the leaves or with Spinosad. If your trees are too large to spray or you just don’t want to, they will not kill your trees. The tree will leaf back out in the Spring.  I have had customers say that early in the mornings they could hear them chewing the hard oak leaves. Crunch, Crunch, Crunch!

Powdery Mildew on Mesquite Trees

With the cooler temperatures, shorter days and rains in the past few weeks, powdery mildew fungus has attacked mesquite trees. Since the trees are getting ready to drop their leaves for the winter, it is not necessary to spray them. They will leaf out and be fine next spring.


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Reader Interactions


  1. brooke burbach says

    What can I spray to kill asps, I think that is their name. A caterpillar that is quite harmful if touched. Thank you, Brooke

  2. james s gill says

    Come in and ask for a product with Spinosad, but bring a sample of the problem with you. It possibly is an asp, but more likely a gall (see earlier blog), this would be an uncommon time of year for asps. There is one type of gall (common right now) that looks just like an asp, but requires no action..

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