Lot of truth here...Don`t know how old you are, or if you mind working for your birds...but my brother and I have walked ditches in SD for years, with very good luck, either with a dog or without. The reason I ask about working for birds, I once finished my 8th section, mile a section, when a truck pulled up and asked if I was having luck. I told him I`d just killed my last rooster. and was filled. He asked where my truck was, at the time it was three miles behind be..he couldn`t believe I`d walked three miles. When I told him I`d just finished my 8th, I thought he`d faint. They hadn`t a thing..driving all day.
We found ditches very productive...shortest walk was 7 min...a double, then a single, done. The neet thing about this, is you don`t have to pay, ask permission, or worry about stumbling on someone elses property. We drive the country, look for a field that has been cut..if the ditches are full of grass, get out and hunt. My brother drops me off, drives down to the next section line, walks it, I pick up the truck and go to the third and so on. Nice thing about ditches is the birds are contained in a smaller area...yes they can run ahead..if your brother is ahead, he can block. But if you walk as noted above..zig-zag, stop, etc, many birds will hold and get up at your feet. Oh, make sure you walk the grass to the gravel road..many hold right there and if you don`t, you`ll miss them. Ask me how I know. If the bird drops over the landowners fence, you can do an unarmed retrive..put your hat on a fence pole so you can find your shotgun..if you have to run down a bird, you can get turned round..never lost my gun, but was worried a few times. We hunt up round Redfield..third week of season..hunting starts at 10. My brother is in poor health now.. will not be going anymore,but we did this for 47 years..brought the kids up doing same....Love it...I gotta get back out there.
YMMV, but Good Luck..