Can pasture give your horse good fresh folage?

Yes. It is perhaps the best way to feed your horse as this is what horses evolved to eat. Often pastures provides a horse with adequate nutrients than what hay and grain can provide. It is best if the pasture has several different grasses because this adds to more diversity in tastes and nutrient-intake for your horse, as different species of grasses tend to take up nutrients differently. But, be aware that lush pasture can be detrimental to your horse's health, because of the high nutrient quality that can be equivalent to a "hot" diet if fed too much too often. This can, most commonly, lead to founder.

A horse should either be fed free-choice hay along with their grass diet, especially in the spring time when the grasses are at their growing stage, or only put out to pasture an hour or two at a time. It is best to avoid having horses graze the pasture when the grasses are at their high-growth stage, and only wait until the grasses are around 10 inches in height before you let them out. One horse should have at least 2 acres to graze on, however this really depends on where you live. You may be able to only graze one horse on 10 acres, whereas others 1 acre is quite enough.

Keep a sharp eye for signs of founder, and only let them out for short periods of time during the day, if you can. If you can't be around to put them in after a short period, have them have access to coarser forage like hay to aid in the digestion process. Also exercise them to keep them from gaining weight on such a good quality pasture.