Have a river bottom field that ranges from ancient marsh to beach sand and the underlying base is glacial till from either 10k years ago or 40k years ago. Too complex to even map. I invite university profs and know-it-all consultants to have a go. Interestingly, no one has taken me up on it so I use it to teach myself humility. This year, it will have corn yields from zero to 280. No P, K or lime for 10 years now – trying to develop a deficiency – but no luck. But it is a heck of a place to learn from.