Plectrodera scalator, the cottonwood borer, one of our largest tree borers, is active in late spring and early summer. This species feeds on cottonwoods and willow.
The cottonwood borer damages cottonwoods both as an immature (borer) and during the adult stage. Adults feed on leaf petioles and tender bark of new shoots. This specimen’s body measured 1 3/8 inches-long. Photog. M. Merchant