Dormant Oil will smother eggs and this can be effective in cold weather. Viburnum leaf beetle has been known in some eastern states since the early 1990’s. Viburnum beetles lay eggs on small sections of branches and are easy to spot when your plants are leafless. Repeated defoliation stresses the shrub and can lead to its death within 2 – 3 years. Viburnum leaf beetle (Pyrrhalta viburni) by Siga (Own work) [GFDL or CC BY-SA 3.0], via Wikimedia CommonsThe VLB larva and adult both feed on foliage and can cause defoliation, and several years of defoliation can kill a viburnum. Step 4 Spray plants with an insecticide, such as carbaryl, permethrin or bifenthrin, labeled to kill the kind of leaf-eating beetles in your landscape. It is a relatively new pest to the Chicago region. The larvae (April to June) can be up to 8mm long, while the adult beetles (late July to September) are greyish brown in colour and around 4.5-6mm long. Manually remove the beetles every day as necessary to help control the leaf-eating beetle population in your garden. Viburnum leaf beetle, Pyrrhalta viburni, a relative newcomer to Michigan landscapes, has quickly affected the health of many viburnums in southern and central areas of the Lower Peninsula.First seen in Michigan in 2003, it attacks many of our native viburnums, including arrowwood viburnum (Viburnum dentatum), American cranberrybush viburnum (Viburnum opulus var. For this reason, treating in the winter with DORMANT OIL is a good way to kill off overwintering eggs. Most of the leaf damage is caused by the stripey, beige-coloured larvae, though later in the year adult beetles emerge, worsening the problem. Viburnum beetles are a species of leaf beetle that feast on shrubs from the viburnum family. The pests can completely defoliate a virbunum. Viburnum leaf beetle larvae are voracious leaf eaters, feeding on the areas between the veins creating a “skeletonized” appearance. In 2015, the beetle was reported across the Chicago region with some regularity. It’s native to the UK, but is becoming more widespread. The adult beetle also causes damage by chewing elliptical holes in the leaves. Viburnum beetle was named as the number one pest by the RHS in 2010, stealing the crown from slugs and snails. A few possible sightings of this pest were reported in 2013 an 2014.