Spray drift is herbicide dollars lost and trouble invited. So consider these nine suggestions for reducing farm chemical spray drift from Dwight Lingenfelter and Bill Curran, Penn State Extension weed specialists.
Aside from the variable climatic conditions this spring, there've been many windy days. Keep in mind that the objectives of any spray application are to balance productivity, efficacy and prevent off-site movement of pesticides.
In some situations, this can be easier said than done. Below are several things to consider to help reduce spray particle (not necessarily, vapor) drift.
•Spray at low wind velocities (less than 10 mph). In general, winds are less early in the morning or late in the evening.
•Reduce spraying pressures. Lower pressures allow for larger droplet sizes.
•Increase carrier volumes per application rate. If possible, use 20 gallons or more per acre instead of 10 gallons or less per acre.
•Select proper nozzles – with coarse spray droplets. Several companies manufacture nozzles that are designed to reduce drift. Some examples to consider are TeeJet AI, AIXR, and TTI; Greenleaf TurboDrop •XL; Hypro Ultra Low Drift, among others.
•Use lower spray boom heights and make sure to use nozzles that have 110° or more spray angle which allows the boom to be lowered more than nozzles with lesser angles, but ensure spray pattern and proper overlap is maintained.
•Reduce sprayer ground speed to less than10 mph). Faster speeds cause more boom bounce and a wider spray vortex, often sending spray droplets higher in the air.
•Use drift retardants. There are many good products on the market.
•Spray when wind direction is away from sensitive crops, homes and etc.
•Invest in "high-tech" sprayers, using pulse modulation, for instance. The pulsing system seems to assist in better application and drift reduction.