I checked a small grain field yesterday afternoon and was noticing abundance of aphids. They were hit or miss a few week ago, but I am now seeing aphids each spot I stop in the field. Aphids are soft-bodied insects in the “true bug” family (Hemiptera) which means they have piercing-sucking mouthparts. They suck juice from the plant but are also disease transmitters. Barley yellow dwarf virus is a disease they vector. Wheat can be damaged but oats are more susceptible. BYD is present in most fields throughout GA and yield losses of 5-15% are common. Yield losses are greatest when plants are infected as seedlings.
Wheat is tillering good now and standing 6-10 inches tall. At this growth stage, our threshold is 6 aphids per row foot. The field I was in was broadcasted, so its more difficult to count. At every location I checked, I was seeing 1 or 2 aphids on a plant. Since this field is at threshold, should be treated. The aphids I found were bird cherry-oat aphids, which UGA Extension Grain Entomologist Dr. David Buntin says is the main species that transmits BYD virus in the winter. A lambda cyhalothrin pyrethroid such as Karate or similar product is recommended to treat for these aphids.