The pest is a rose cane borer. The adults bore into the end of a cut rose cane to deposit their eggs, the eggs hatch and you saw the green larvae of the insect. Spraying the rose with an insecticide will not help to control the cane borer as they a covered in the middle of the cane. To control the rose cane borer, cut back the cane an inch or two at a time until you do not see the tunnel in the middle of the cane. Immediately spread Elmer’s White glue over the cut end of the cane. When the glue dries it will provide a protective cap over the cane so the cane borer can not bore into the cane. Any time you prune your roses cover the cut with white glue.

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