Pre-harvest herbicide applications may be considered in fields where small grains are grown for seed or forage. Dense weed populations may inhibit harvest. Although spring is the most effective control period for annual weeds, some weeds escape or late emerging weeds may cause problems near harvest so herbicides may be applied to desiccate and suppress weed escapees. The greatest risk for yield reduction is the period 5 to 7 days before heading until 7 to 10 days after heading, including pollination and kernel development.
Basic Pre-Harvest Tips
- Use effective early season weed control tactics and products.
- Scout often, spraying must be done within 10 days of bloom to prevent weed seed production.
- Increase spray volume to 15 gal/acre or more.
- Spot treatment can be a useful tool.
- Hand rouging or clipping of perennial weeds may be effective.
View the 2018 South Dakota Pest Management Guide: Wheat for South Dakota small grain pre-harvest recommendations.