Greenbug
Schizaphis graminum (Rondani)

These are lime-green aphids about 2 mm long with a darker green stripe down the middle of the back. Cornicles are short. Legs and cornicles have black tips. Their saliva is toxic and kills the plant at the feeding site, causing purplish-brown discoloration of the foliage. It can serve as a vector of barley yellow dwarf virus. Host plants: cereals, bluegrass, sorghum, buckwheat.