if you ever make it to this part of the state (central OK) stop by Ross Seed company in El Reno and pick up 100# of their spring wildlife mix. You can't beat it--has a mix of cowpeas, soybeans, alfalfa, millet, milo, and grain sorghum. Produces all summer long and gets lots of activity.
If you want to go with a pure stand such as soybeans, like William stated, you need to contact soybeanman with Eagle Seed and order his forage RR ready soybeans. Those beans can handle the pressure.