As I was out enjoying the beautiful side of horticulture this spring, I could not miss the no-so-nice evidence of the viburnum leaf beetle (Pyrrhalta viburni) (VLB) feeding on arrowwood viburnum (Viburnum dentatum) in the phenology garden at the OSU Extension, Lucas County Office at the Toledo Botanical Garden.
While first egg hatch of VLB occurs at GDD 210, it is obvious that have been busy. We are currently at 506 GDD.
The larvae will continue to feed until they drop to the soil and pupate underground. The adult beetles will emerge and make their way back to the shrubs and continue feeding where the larvae stopped, causing additional injury to the host plants. Adults will mate and the female beetles will lay eggs in the tip end of the viburnum branches where they will stay until next spring when they hatch. There is one generation per year.
Fellow BYGLer and member of the Buckeye Environmental Horticulture Team (BEHT) authored a FactSheet on this non-native invasive insect that continues to spread across Ohio. The FactSheet can be found at: https://ohioline.osu.edu/factsheet/anr-39 It includes all of the information you will want about VLB and the host plants, including management options.
If you are seeing VLB in your area, we would love to hear from you. You can report your observations using the Great Lakes Early Detection Network (GLEDN) App. If you haven't already downloaded this free app and want to learn more, check out the following links:
Ohio Woodland Stewards Recording, Great Lakes Early Detection Network: Helping Land Managers Track Invasive Species – August 7, 2020
If an app just isn't your thing, we still do want to hear from you if you are seeing VLB. You can email firstname.lastname@example.org with the subject line: VLB Observation with information including county, city and a photo.