Applicators using ground sprayers for herbicide may be using higher speeds to catch up with weeds and cover more acres in a narrow time window. If so, they should consider the travel speed they've used to calculate appropriate nozzle size. If field speed increases by 25% (e.g., going from 12 to 15 mi/h), spray pressure for a given nozzle must increase by 56% (e.g., from 40 psi to 63 psi) to maintain output. A better choice to reduce smaller droplets and minimize drift would be to increase nozzle size.
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