I use hay. It depends on how old your horse is on how much much you give them. My horse is 3 and I give 3 flakes, my sister's is 8 and she gives him four, but it depends on your preference
It is food the horse finds for itself when it is released.
A horse in a good pasture will do.
Yes
Yes that is the most common way to get fresh forage
You can place your horse in the pasture in order to give him forage. So long as he stays there long enough to give him the amount that he needs, you will not need to feed him forage from the feed box.
Hay (forage) and grain if they need it. Each horse's diet should fit them specifically based on their needs.
You feed your horse by clicking the feed link to the top left of his page and selecting the amount of forage and grains to give.
It can so long as the grass is of good quality and there is at least one acre per horse , 2 acres are better.
Depends on how big the pasture is, how many horses. If there are more horses than year round forage, I'd suggest hay. It also depends on what grows in your pasture? Any alfalfa or timothy? Those are really good for the horse(s).
450?
The amount of concentrate a horse requires has generally got nothing to do with its breed (although obviously a Thoroughbred will need more than a Shetland pony.) Provided that there is sufficient forage, a horse that is left to its own devices and not ridden or worked does not need concentrates unless the forage is of poor quality. The amount of concentrates will increase proportionate to the amount of work it does. A Thoroughbred racehorse or eventing horse in full work and training will need a lot of concentrate to fuel those massive muscles. I'll look up a forage/concentrate ratio and post it here later. The amount of concentrate a horse requires has generally got nothing to do with its breed (although obviously a Thoroughbred will need more than a Shetland pony.) Provided that there is sufficient forage, a horse that is left to its own devices and not ridden or worked does not need concentrates unless the forage is of poor quality. The amount of concentrates will increase proportionate to the amount of work it does. A Thoroughbred racehorse or eventing horse in full work and training will need a lot of concentrate to fuel those massive muscles. I'll look up a forage/concentrate ratio and post it here later.
A horse needs to consume at minimum 1% of it's body weight daily, but 2% is better.