Viburnum leaf beetle (Pyrrhalta viburni)

Description: Native to Europe and detected for the first time in the United States in 1994 in Maine. It has now spread to CT, IL, MA, MI, NH, NJ, NY, OH, PA, VT, WA, WI.

Identification: Adult beetles have a golden, metallic sheen when observed in direct sunlight. This is produced by short, gold-grey hairs. Head, thorax and wing covers are golden-brown but shoulders and front edge of wings are darker brown.

Hosts: Native to Europe. Consumes a wide variety of viburnum species but the most suseptible are Arrowwood viburnum (V. dentatum), European cranberrybush viburnum (V. opulus), American cranberrybush viburnum (V. trilobum), Rafinesque viburnum (V. rafinesquianum).

Life Cycle: Life stages include egg, 3 larval instars, pupa and adult. Over winter in egg stage and in mid-May, eggs hatch and the larvae disperse. As they grow, their feeding intensifies and once larval feeding is complete, they enter the soil below their host tree to pupate. Pupal stage lasts 10-14 days and no damage occurs during this time. Adults appear in late June to early July. Females chew holes in small branches or twigs for egg laying. Sites are arranged in straight rows on the undersurface. Females can lay up to 500 eggs. Adults mate throughout the summer and fall until first frost. Normally, one generation per year.

Monitoring and rapid response: Several insecticides will list viburnum leaf beetle on the label. May be sprayed when larvae first appear but repeat sprays are necessary for adults. Spraying againsts adults is not effective for control. Horticulture oils and insecticidal soaps can be helpful. Mechanical control can also be performed by removing and destroying infested twigs after egg laying has seased in the fall (Oct-Apr).

Credits: The information provided in this factsheet was gathered from the Ohio State University Extension .

Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org). Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).

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