Well that'll depend on how much and the type of grass. If it's sparse and of poor quality you should supplement the diet with hay. If the grass is plentiful and lush probably not.
they graze on grass and hay
grass & hay
Hay
a white horse eat hay and grass
Hay as well as horse feed and grass.
mainly hay or grass
I'm not familiar with this breed but if it is equine it most likely eats grass and hay.
Orchard hay is a type of grass hay grown from orchard grass. This type of hay is excellent horse feed, but can be fed to most any grazing animal.
Horse fodder is basically the food a horse eats. Hay, chaff, grass.
A wild horse mostly eats grass ,hay and berries.
A horse eats grass or hay and no animals.
you can feed you horse hay, carrot and other vegges and dont forget grass