Chemega at Winterbourne Monkton supplies a lot of the chems for the crops in the area.
Growth excelleraters/inhibiters, pesticides, fungicides, ripeners etc.
Most of the flattened crop can be harvested by a skilled combine driver by lowering the blades.
The crop damaged by walking across the field instead of the tramlines cannot be collected which is why the farmers get so annoyed about it.
Some farmers have taken to listing the chemicals sprayed on the crops at cropcircle sites to protect themselves from being sued by american visiters.
PeteG