OK, I've seen enough of my experimental summer plots to make a report. I wanted to see what would happen in the worst case scenario, so I did NOT spray my winter plots before turning them under. They were 24" tall wheat seeding out and blooming crimson clover when I turned them under. Then I broadcast 30 pounds of RR production soybeans, 30 pounds of iron and clay peas, and 20 pounds of buckwheat per acre and covered them by dragging a heavy chain harrow. I did not spray with roundup because I didn't want to kill my non-RR plants. Plots did pretty good for 6-7 weeks, but primarily the soybeans and buckwheat. Not impressed with the iron and clay peas (low germination, slow growth, moderate deer utilization). Was surprised I did not see the deer utilization of buckwheat in summer like I do in fall. Deer went crazy over the soybeans. By about 7 weeks, foxtail and other grasses overtook the soybeans, which are now buried in grasses. Deer as still going down into the grass to get them, but much harder to find.
For next year, changes will be:
Doubt I will spray winter plots before tilling because I will be going all RR summer crop.
Will broadcast Eagle Summer Managers Mix at 150% the seeding rate for drilling.
Instead of dragging with the "flat" side of the chain harrow, will bury seed with "tine" side of harrow (flat side produced too much compaction, and drug the seed around too much).
Will hit plots with Roundup 4 weeks after germination (once as much weed/grass seed as possible has germinate but not before it gets up above 6").
Might try a slow rotational planting of fall plots so not all plots are turned under at the same time. I'm usually pushing hard to get all fall plots in when the weather is right, but if the summer Eagle soybeans are doing well, I might transition a few plots at a time over a month or 6 weeks.