00rooster - 5/11/2016 18:15

Works good as long as your pivot travels quickly. If you put the high speed gearboxes on and tall tires you are probably actually watering about .1" or less. If you run that around in July or August on a nice sunny hot day probably 75% of the water will evaporate on the leaves and never hit ground if your crop has a full canopy. And you actually cover the entire plant in a low dose of fungicide instead of coating just the top leaves with a concentrate.

This type of application is also why some people still prefer the sprinklers on their irrigation instead of drop nozzles. And as Variable rate irrigation becomes more popular I expect that someday soon you'll be able to adjust the droplet size and volume from the panel. Then you can use the large droplets to minimize evap when watering, and smaller droplets and higher pressure when chemigating.

Even then you won't see good results on a dewy morning, you want to wait until you'll get evaporation during the hot part of the day. Ideally you would want to complete a circle in 10 hours so you can apply from 10 am to 8 pm. That would maximize the evaporation of the water instead of having it fall on the dirt.