Schizaphis graminum (Rondani)
Greenbugs are pale-green aphids with a darker green stripe down the center of the back. Greenbugs are typically found feeding on the underside of lower leaves. Feeding damage to wheat can occur in fall or spring, which is first observed as reddish spots around feeding sites. Damaged leaves eventually turn yellow, then reddish brown and eventually die. In the field, damage often appears as yellow or reddish-brown irregularly shaped patches that can spread to become almost field-wide.
Source of information
Frank Peairs (Colorado State University, Bugwood.org), Department of Entomology (Oklahoma State University)
Pest photo source
Wendy Johnson, KSU Entomology