Oak tree infestation - Ask Extension
We have a 40+year-old oak tree that is infested with caterpillars (photo attached). The driveway is covered with castings (is that the correct term?) ...
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Oak tree infestation #270148
Asked August 14, 2015, 1:42 PM EDT
We have a 40+year-old oak tree that is infested with caterpillars (photo attached). The driveway is covered with castings (is that the correct term?) and multiple caterpillars that have dropped from the branches, some of which are totally denuded of leaves. What are these pests and is there a systemic liquid that I can use to rid the tree of these pests?
Howard County Maryland
Expert Response
We have been hearing of these in the Howard County area.
This is an Orange-striped Oakworm. This creatively named caterpillar is not of great concern on older oaks, especially this late in the season, as most trees are able to recover from the damage. You may not see them in future years.
We do not recommend any controls, but there is an ichneumonid wasp that parasitizes this caterpillar by laying eggs under their skin, which hatch and then eat their way out, helping get rid of them.
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This is an Orange-striped Oakworm. This creatively named caterpillar is not of great concern on older oaks, especially this late in the season, as most trees are able to recover from the damage. You may not see them in future years.
We do not recommend any controls, but there is an ichneumonid wasp that parasitizes this caterpillar by laying eggs under their skin, which hatch and then eat their way out, helping get rid of them.
cm
