No Jumping to conclusions. Read my earlier post and you'll see I already made suggestions in that regard, to which the OP already responded that he had already looked into it."Well, you've done your part in gathering information. You should call your nearest FAA Field office and report it. It's very odd for him to be flying such aircraft and in such manner, being so far from any workable area (those things aren't cheap to operate either). The aircraft owner may also take exception to wasting fuel for no apparent reason. You could easily make his "joy rides" less enjoyable. Best of luck."
It seems there's a lot of jumping to conclusions about the intent of the pilot and his flight parameters. Not all such flights are related to agriculture. For instance, do you have a local mosquito control district or a problem with an insect infestation that's more widespread than the extent of local croplands? Such planes are also used for wildlands fire suppression. The state of Colorado owns a couple of them expressly for that purpose.
As far as I am aware, the Agcat has been dropped in favor of the more efficient Air Tractor series for every operation, except agriculture...and that is dying, seeing that there hasn't been production since 1995. There are none in use for fire suppression at all.