A spraying expert says potential spray drift is a significant concern and payloads will likely be too small to be productive
 Drone sprayers have been used in Pacific Rim agriculture for more than two decades, and they gained California certification four years ago. But do they have potential beyond the orchard gate? Probably not, at least not in the foreseeable future, according to Tom Wolf, also known as the Nozzle Guy, in a recent post to his Sprayers101 Agrimetrix website. Drone advocates say a drone can access problem topography or saturated soil where your self-propelled sprayer cannot go. True, but those are the areas you can’t farm anyway. Your tractor, seeder and combine won’t enter those areas, so why should your sprayer. He said a drone payload is relatively small. With those small payloads, application volumes will be too low to have any sort of productivity. “While OK for spot spraying, it represents a serious productivity constraint for anything larger. There will be a push towards lower volumes, perhaps 0.5 to one gallons per acre. The only way these will provide sufficient coverage is with finer sprays, (American Society of Agricultural and Biotechnical Engineers...