I have been getting questions about aphid thresholds in oats and other small grains. Growers or scouts should inspect fields 25-35 days after planting, full tiller, and heading. Yield-reducing transmission of Barley Yellow Dwarf virus can occur during the first two periods; transmission at heading is too late to reduce yield. According to the 2020 UGA Pest Control Handbook thresholds in small grain include treating when aphid populations reach or exceed the following thresholds at various stages of development:
- Seedlings: 2-3/row ft,
- 30-60 days after planting: 6/row ft;
- 6-10 inch plants: 1 to 2/tiller
- boot to heading: 5/stem
- heading to dough stage: 10/stem hard dough to maturity: damage not economic.”
If you would like more information about insecticide selection in small grain it is available in the UGA Pest Management Handbook.
More information about Barley Yellow Dwarf is available here
More information about insect management in wheat is available here
If you have any questions please contact your local County Extension agent.