I don't know if anybody has mentioned this yet, but everyone needs to know it.
DO YOU HAVE A RED MAPLE TREE? If you do, keep it away from horses. It's a thing called red maple toxicity. Red maple leaves in the wilting stage are DEADLY to horses. I found out through a lady who had already lost multiple horses to it. Apperently, they had a storm and a red maple limb fell in the horses pasture. In the morning, the horses started eating on the leaves. It acted as poison and killed a few of the horses and put others in critical condition. If you have a red maple tree near horses, GET RID OF IT! That's all I heard really, but it was very serious and I thought you guys would want to know.