I have a total of 70 acres and with the bermuda grass I think I could realistically run about 70 commercial cows.
So, what you're really saying is you think you could realistically run about 1 commercial cow per acre. Is that with you assuming that ALL of their feed needs are coming off of that 70 acres, or is there some outside hay/grain/supplements being fed that didn't originate on those same 70 acres?
It always bugs me when people quote these kinds of numbers... but then they don't include any "outside feed" that's being fed in their analysis (feed that came from acres "other" than the pasture they were physically grazed on through the summer). Most operations do this... they have "summer pasture", and then a "winter feeding time", where they feed bales, grain, supplements, etc. But NONE of that other feed had to be raised on the "summer pasture acres" WHILE IT WAS ALSO FEEDING THE COWS IN THE SUMMERTIME. So when figuring that extra feed in THEN, what does THAT do to your "cows per acre" number.............. It's goes down......... dramatically.
Alot of guys up here were already feeding hay in June this year, and ended up having to keep feeding hay right on through into their normal winter feeding schedule, because of the drought. NONE of that supplemental hay came off of those summer pastures, and none of what they feed normally in winter typically comes off of the summer pastures either. They typically will have a "hayfield", or some acres dedicated to corn for silage, etc., or they buy in hay grown on somebody else's acres. ALL of those acres though are required to reach the overall density that you're asking us to inform you of.
Sounds more like TheCowGirl is intending to be supplemental feeding these things all the time, and she's more looking for an exercise lot for the animals than she's looking for them to be getting all of their feed off of what it might actually be able to grow for them. BIG, BIG, BIG difference.