Sprayer boom height reminder
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
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This past week, I calibrated a sprayer that had Teejet XR 8002 nozzles. This is an 80 degree angle nozzle designed to operate at 30 inches above the target for the recommended 100 percent overlap coverage. In this case, the target was weeds, so the boom needed to be 30 inches above the average weed height.
Spraying 30 inches above the target will subject the spray to more drift. As farmers scramble to get corn and soybean weeds sprayed, summer-like weather can be windy with more off-target drift potential.
In the above situation, I suggested the farmer consider switching to an XR 11002 nozzle. This is a 110 degree nozzle that only needs to be 19 to 20 inches above the target to get the recommended coverage. Other than the angle of spray pattern and the lower boom height, these nozzles will both perform exactly the same for the recommended nozzle pressure, gallons per acre and ground speed that the farmer wanted to use.
The boom height target in this case is the weed height. Although spray record requirements do not include boom height or nozzles used, or specify detailed weather and wind conditions, more information is better for potential drift complaint reasons. Remember also that grass weeds will be harder to control if the gallons per acre applied is lower and/or the ground speed is higher and these factors are not adjusted for better coverage of grasses.