Knock out roses going round 2

Asked May 24, 2018, 9:54 AM EDT

What is causing the leaves of my knock out roses to loose chlorifil ( as if something is sucking it out) and be eaten and how do I get rid of them?

Caroline County Maryland shrubs roses pest insect and mites

1 Response

This looks like heavy damage from rose slug sawfly larvae. We can see two of the larvae (tiny green caterpillars) in your second photo. It is a very common problem in roses, including the Knock-outs. To control heavy infestations, use horticultural oil or spray with spinosad insecticide. Read and follow the label instructions when you use these products. Target the undersides of the leaves to get good coverage. Here is additional information about rose slugs and how to manage them: https://extension.umd.edu/hgic/rose-slugs-shrubs

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