well the yield is terrible on it too....3 combined windrows of alfalfa hay made 1 bale.....so to get enough for a 100 cows im guessing you need about 1000 acres of alfalfa...
sounds like you didn’t fertilize. I set yield for alfalfa to 6-8tons per acre. Plenty for cows. F12 doesn’t fertilize fields if you’re using PF so keep that in mind and make sure your nitrogen and lime are in good levels