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 b...