Rod, weeds are an indication of lack of fertility...after years of crop farming, what do you expect? Higher class of plants require higher fertility. To maintain or develop grassland, you have to manage your land as grassland...herd effect. Fertilize part of one of your pastures and see where your cows stay.
Two problems with going to an all grazing operation...it requires more management to insure your cattle have something to eat year round(which includes feeding them hay when needed)...second, ruminant-hog genetics that dominate North American cattle genetics don't work...been there, done that! Combine those two and you get the ugly situations you are seeing.
NR, I talked to Gearld about breeding two year old heifers. Part of his thinking was for a total grassfed operation. Raise the heifers the same as meat steers, expose them and preg check in 45-60 days. Heifers that weren't bred would be finished and ready for slaughter...better cash flow. As I'm sure you'll agree, I told him that if I waited until two to breed, they would all be bred! He also said that at two they would be more sexually developed, but isn't that what we are looking for by breeding as yearlings...early maturity? He also sighted research that claimed a longer reproductive for cows that were bred later.
Robert