Where is it you are going? North central is pretty much all ag ground, so if there is some CRP you should probably find a few birds. It can be weird though, with no pheasants in one place, and lots just a mile or so away. We used to hunt around Shell Rock IA when I first moved out here (mid 90s) and shot lots there. The farmer had his waterways in CRP and it held many many birds. Then corn prices went up, government reduced the CRP program, and the bird numbers suffered. I haven’t hunted birds much in the past 20 years, but did go one time with a buddy on his farm last year. It is only a 100 acre piece, but is the perfect piece for birds. His is all CRP and is surrounded by ag fields.
Let me know when you are going, and if you will be close (his farm is just south of Center Point IA), maybe there would be a chance we could walk it if you are having 0 luck where you are.