Rockhound, I would disk up the borders and let them go wild- blackberries, broomsedge, beggarslice, ragweed, etc. These are prime brood rearing cover. Disk 1/4 to a half each year. Deer will eat the buffer as much as the food plot, and you won't give up "sightability" during deer season like you will with tree planting. If you decide you want them thicker, don't disk, and the trees will creep in.
OR
Plant a strip of clover around the wild stuff and 2-3 strips across it. burn the patches between the clover strips in the spring for turkey hunting, and it will grow back just in time for them to raise their broods in it. Deer love these fields as well.
If you are wanting to provide nesting sites, you could cut down scattered (10-20 per acre) low-value hardwoods throughout the woods. Turkeys love to nest against structure, especially logging slash, and if you distribute them throughout the property, the coons and skunks have to work much harder to destroy those nests.
If the only nesting cover you provide is right next to your food plot, your turkeys have one-stop shopping, but so do the nest predators.