With horses "intensive grazing" takes on a whole new meaning. Our current pasture management plan is the result of 8 years of thoughtful
experience on this property. We have 3 horses pastured about 8 acres of '
native' field grasses/weeds (we never planted seed). Our grazing space is divided into 11 individual pastures (2 added this spring), rotated weekly. We try to never let summer grasses get grazed to a depth shorter than 6 inches. Our planned "winter" fields we stop grazing before the end of August. This allows them to develop "layers" of forage. The top layer being tall stalks and seed heads of weeds/grasses (which the horses adore), the second layer being tall weeds and grasses that have "slumped" over but still maintain a lot of green stem in-winter, the final layer is green grasses that reside under the protective cover of the first and second layer. This third layer the horses will dig through the snow to consume. Even in Michigan's bitter February and March months it is green and nutritious for the horses. We, also, are mindful not to over-graze our planned spring pastures. We've found it best to NOT let the horses graze those tight too the ground before the early winter frost (the previous year). Letting the spring pastures go long in the fall seems to help them green-up much earlier and, really, develop mass very quickly.
This past year has been our most successful (in part due to the mild winter). We purchased and fed a total of 30 bales of first cutting hay for the entire 2011/2012 winter season. This spring we've fed zero hay and I do not anticipate feeding any hay until, maybe, February 2013.
This year, we will be applying last seasons lessons and two new pastures. I'm going to try and rotate in
chickens to follow the horses on the pasture rotation. That means that each pasture will have, at least, 10 weeks of rest before being put back under stress. I hope to have such a stockpile of forage that I will never have to buy hay. Maybe I won't ever get there, entirely, but I've gone from feeding 300 bales in winter to 30 bales. That is no small savings!
Edited for typo.