English grain aphids are a tiny pest of small grains and are found throughout the grain growing regions of the United States and Canada. Like other aphids, they have short generation times and their population can grow rapidly under the right conditions.
English grain aphids feed on the leaves of small grains, sucking the plant juices and weakening on the plant. Once the plant heads, the aphids feed directly on the developing kernels, reducing yield. They are also a vector for the barely yellow dwarf virus.