I remember one year back in the mid 80's we round baled over 1000 acres of wheat stubble that had fire weeds about 1' to 1-1/2' tall. I can't remember how many bales we ended up with but it was well over 3000. We ran every bale through our tub grinder and blended it with about 10% to 15% sorghum silage and feed it through our mixer box. We supplemented protein tubs. Depending what it was being feed to either pregnant cows or yearling calves as each of those herds was presented a different type of protein. Every morning, the bunks were clean, I would say less than 5 % waste and cattle wouldn't hardly touch the alfalfa bales that were available in other feeders. Can't recall exactly what the calves gained a day, but I know it was over 1#. Didn't hardly have any issues with new born calves that year either. The key is you've got to find the right mix that the cattle will eat, and that year we nailed it on the head. Ah, the memories of high school. Good times, Good times. 
FWIW, I stacked every bale with a open station 930 case and a single 3pt. bale fork. Best summertime sun tan I every had. 
