Unknown caterpillars were found defoliating a euonymus shrub in Ramsey County recently. They were identified as Euonymus caterpillars, Yponomeuta cagnagella. The larvae were up to ¾ inch long, cream to yellowish colored with rows of black spots. These caterpillars also produce silk and can envelop branches, even entire plants, with their webbing. They should not be confused with the feeding and webbing of eastern tent caterpillars. Eastern tent caterpillars primarily attack flowering fruit trees, such as crab apples, cherries, and plums and create their tents in the forks of branches.
Euonymus caterpillars are European in origin. They were first found in North America in 1967. They have been reported sporadically in the Midwest, e.g. in Wisconsin, Illinois, Iowa, and Michigan. This appears to be the first time euonymus caterpillars have been reported in Minnesota, although it is possible that they have been seen before, but not reported to the University of Minnesota.
We would be interested to learn of any other incidences of euonymus caterpillar in Minnesota. If you believe you have seen it (and live in Minnesota), please report it to the author at firstname.lastname@example.org. Please include any photographs of the insects or their damage. For more information see: Euonymus caterpillar (U of WI publication.
|Have you seen euonymus caterpillars? Photo: Linda Treeful RCMG|