There is no problem with paying farmers for access, legally, but some may be insulted.

I have brought many of my farmers fish, or asked if there were any services that I could provide. One group of farmers has me come down every month or so to cull their feral pigeons with pellet guns, over 400 to date. I have even made some elaborate bird feeders for a few, and all of these things have cost me less than $20.00 in cash, but showed the farmers some thought and effort on my part.

Just some other ideas, Andy.