This Chrysomelid leaf beetle has a targeted host range and in nurseries it is found on occasion on coreopsis, also known as tickweed. You can find mention of it as coreopsis beetle or even tickweed beetle. It is also reputed to feed on ragweed. Both adults and larvae feed causing leaf skeletonization. There is limited information available on this insect. The adults have been found in the late May-early June here in Oregon. This is also a time when they are noted mating.
Management note: Some nurseries use the Bt var. tenebrionis (Novodor) to control the young larval stages of the beetle.
Web resources:
Blackstone, Victoria. About the Coreopsis beetle.
The Home Garden: Calligrapha leaf beetles. This site has images of the larvae and their damage.
Orginal publication: 6/6/2011
Latest publication: 12/14/2016
Author: R.L. Rosetta, Extension Nursery Integrated Pest Management, Department of Horticulture, Oregon State University
Gallery
Calligrapha californica adult
Photo: Karl Puls, Oregon Department of Ag Calligrapha beetles often come in bunches. It is not infrequent to find mating pairs
Photo: Cindy M.
Calligrapha californica adult
Calligrapha californica adult
Calligrapha californica adult
