Proper mixing key to avoiding crop injury. Crop injury from pesticide residue often starts at the chemical mixing stage, says Emile deMilliano, manager of agronomic services with Viterra. "If I look at the situations I've seen in the field where we've seen improper tank cleanouts and injury to crops, it often starts with not doing a proper job of mixing the products. You have to ensure the product gets into solution."

Venturi nozzles only part of the equation, says specialist. "Although venturi nozzles have been known to cut spray drift by half, the fact is that you still can't spray into 25 to 30 mph winds just because you're using a venturi nozzle. There are still other factors to consider, and in today's farming environment, it pays to start thinking about them well in advance of spraying." – Brian Storozynsky, sprayer technology specialist, AgTech Centre, Lethbridge, Alberta.