If there is any power lines near the corn fields, scan those good, doves will habitually land on power lines. Just don't attempt shooting them off the lines, for obvious reasons I'm sure you're aware of
Doves also make several sounds that is easily recognizable and could help you ID 'em before the season starts.
When taking off and landing, their wings make a loud 'whistling' sound. They also have a unique 'call' when perched on the power lines or in the tops of dead trees.
Maybe try searching online for 'mourning dove sounds' could help you out..
When flying, they look similar to pigeons, only smaller and faster. You'll get the hang of it pretty quick.