I have found them in the trees --- walleye spots. The thing is about crappies ---- they don't get along with walleyes. If you start catching a lot of them ---- your walleye pop is going down. Same with largemouth. I don't know if it lack of IQ or what but the smarter fish don't get along with walleyes (walleye fry are easy pickin for them big mouths and white lips).
I have caught crappies every time I have fished the ND side of oahe. Generally along the banks - close to trees.