Corn is hard on a soil....so the comment about your future plans for the area are warranted in my opinion. If you are simply looking for tall annual bedding cover.....I would look into the products specifically for that purpose (WI conceal comes to mind) or for game birds. These products often times contain a mix of tall and short sorghum, millet, EW, sun hemp and tall variety sunflowers. I think a mix like this may be cheaper on your wallet, easier to plant and actually provide the cover that your looking for better. I have never used these products before.....but I feel it may be worth looking into as an alternative.
Corn - even if not wanting grain, hates competition (if you let the weeds do their thing to enhance the cover you will get 3 feet tall corn plants that are very weak (otherwise your planting RR seed and spraying). You will probably still have to use an actual planter for the best results density wise, and if for some reason you get too much or too little rain....then your really screwed. And if you have turkeys....I see it all the time where they will walk the rows of a field right when the plant starts to pop and they pluck as many as they can from the rows.....which means they could wipe out a small area fairly quickly if you have a lot of birds.
