Some details on above: I would encourage every hunter new to SD to start out with scouting drives during hunting hours opening week until you see them on the road or in the ditch and then get out to do short walks in those ditches. They will hold in ditches for a single walker, or a dog flushing them out or two people with one blocking up at the next road approach. Even mowed ditches this year can work as the birds are either in the grass under the fence line or they are holding tight to the ground in the bottom of the ditch. They can disappear in about 12 inches of grass when they need to. It's a versatile approach for any situation and gets you hunting regardless of whether you can find private or public fields to walk. Birds are going to and from feeding in these cases so staying in front of corn fields is key. Bigger the cornfield, the better. The more corn fields in the area, the better. This year in dry conditions, finding water sources next to corn fields will likely really concentrate the birds. Bird numbers vary a lot within 10 mile so you need to get out of areas where you see just a few and find areas that do have numbers- and then keep circling that area.
You get to see lots of the countryside, put an eye on walk-in locations to come back to later in the season and you are guaranteed to have miles of open country to yourself. Keep in mind I am an out of state hunter, frequently without a dog and only hunt opener so I have a different set of conditions to deal with than many frequent posters on this board. They are after a different experience since many are local to SD or nearby so they have many weeks to pick and chose for hunting, have hunted a long time in the area and have fields picked out to bring their skilled hunting dogs that have benefitted from regular exposure to birds. They tend to be older, want cool weather for easier walking, big open fields to run their dog/s and no crops in the field so the birds are concentrated in the grass. They can wait until the crowds leave and enjoy the controlled conditions of hunting alone without the complexity of other dogs or hunters in the mix. I may kid them a bit about our differences but what they have is a very good thing and I don't begrudge them for encouraging more people to achieve what they have going. I have the same desire for novices to get out and have success early on so they some day can get to the position that they skip opener and wait for the crops to come off too.