It has a body length of 2.0 to 4.0 mm. The cornicles of this aphid are characteristically long and slender. Pea aphids extract sap from the terminal leaves and stem of the host plant. Their feeding can result in deformation, wilting, or death of the host depending upon the infestation level. Plants that survive heavy infestations are short and bunchy with more lightly colored tops than those of healthy plants.
Wilted plants appear as brownish spots in the field.
Moreover, plants are often coated with shiny honeydew secreted by the aphids, and cast skins may give the leaves and ground a whitish appearance. Alfalfa Aphids in Oklahoma .