Roundup Record Tribune & Winnett Times -

Throughout the Roundup area and Musselshell county, there have been significant effects to cottonwood, aspen, poplar, and willow tree species. The pest responsible for this defoliation is the cottonwood leaf beetle, Chrysomela scripta Fabricius. The adult beetles are characterized by having a black head and thorax with yellow or reddish margins on the thorax. They have yellow and black stripes covering the elytra.

You may, also, see the beetle in the larval stage. They are black in color and will turn light to dark brown with white scent glands as spots along the body. The cottonwood leaf beetle larvae may look similar to lady beetle larvae. Eggs are laid on the underside of the foliage, in clusters of 15-75 and are yellow in color. In terms of managing this pest, there are a few different options. Trying a horticultural oil, neem oil, or insecticidal soap would be the place to start. Some examples include Garden Safe Neem Oil or Safer Brand Horticultural & Dormant Spray Oil Concentrate. Both of these products can be special ordered by Roundup Hardware. Always be sure to carefully read the entire label and directions for use. Target the pest during the larval or adult stage to ensure that they come in direct contact with the chosen control method. Please contact Jennifer Fosjord at the Musselshell-Golden Valley Extension Office in Roundup at (406) 323-2704 or [email protected] with additional questions or information.

Reference:

Chi, A. A., & Mizell, R. F. (2012, April). Entomology and Nematology Department. Retrieved July 23, 2019, from http://entnemdept.ufl.edu/

Photos:

http://www.bugguide.net

http://entnemdept.ufl.edu/