I beg to differ from FL370 Officeboy,
Crop dusting isn't for the faint hearted or the marginal pilot. Take a crop sprayer who's flown turbine equipment and done night spraying etc, then give them a year's line flying and they'll be brilliant. I've flown with a former crop sprayer and his skills were very much in evident. He also taught me a few tips and tricks with the FMS as well.
Not all GA is bimbling around VFR in a single engine fixed pitch prop 4 seater.