Join Date: Oct 2008
Location: Sweden - the land of carrots and apples
At first the title of the thread scared me.. but I see why there might be a question about it now:P
No, horses don't need hay. They are, and always will be, meant to eat grass, herbs and perhaps some leaves and other such thing. When we can't provide enough of that, we give them some sort of hay.
If the hay doesn't contain all of what the horses need, or if it's not balanced in the level of nutrition (like too little protein), we give grain/pellets or other man-made horsefood or supplements, but only if the hay or grass isn't enough.
If the hay is too rich it can be mixed with regulr straw and some supplement might be given to add up for the lack of protein in straw.
Horses need to always have something in their stomachs since they ''leak'' acids in there to care for the food. No food and they sore their insides instead. Grain and other supplement (because that's what all food that's not based on grass/hay should be used as) are not really healthy for horses but can in large quantities poison and even kill them. They're a kind of necessary evil; some horses ned them and of course, given in the right amount they are good to use. :)
But to answer the question; no, horses don't need hay if they have enough grass.
Always keep your head up, but be careful to keep your nose at a friendly level.