bale grazing
If you do have to offer hay in the winter, bale grazing puts the dung and waste hay where they will do the most good. Breaking bales out on the pasture lets you spread impact even without moving fence posts. And with snow on the ground, you can forgo filling the stock tanks and plugging in a deicer.
This is a particularly good dodge for rehabilitating damaged pastures. Not only waste hay, manure, and urine end up spread on the ground, but grass and weed seeds as well.
Breaking up square bales, or unrolling rounds, distributes the carbon over a wide area. If you must park a round bale, you can maximize useage and minimize thatch if you push the bale over on its flat side and wrap the roll with a narrow band of wire netting or welded stock panel. Tying it together like this prevents half-eaten layers of hay from falling off the bale and being trampled into a dense mulch, killing whatever is growing underneath. Cows reach over the wire to eat out of the circle, and since the hay stays clean they eat it right down to the ground.
Come out for our local farm conference in April and we'll talk about it.