Viburnum beetle [Pyrrhalta viburni ] attacks many species of Viburnum plants. The larvae are the most damaging part of the life cycle, which are creamy yellow with black markings with a caterpillar like appearance. They feed on the Viburnum leaves and cause significant damage, shredding the leaves. The adult beetles do also feed but do not cause as much damage. The Viburnum beetles lay eggs in the late summer and autumn that overwinter in the bark and stems of the Viburnum . These hatch in April-May forming larvae that start feeding on leaves. This is the time most damage is caused until the end of June, when the larvae are fully grown and drop to the soil to pupate. The new adult beetles emerge late summer.
How to control
Where possible pick off any larvae that are observed in the spring. If this is not possible or there are to many, apply Viburnum Beetle Killer nematodes directly onto the Viburnum beetle larvae on the leaves. See Viburnum Beetle Killer for more details.