Are autumn blaze maples toxic to horses?

The only species of maple that has been shown to be toxic to horses in the eastern states is the red maple (Acer rubrum). “Autumn Blaze” is a hybrid between red maple (Acer rubrum) and the silver maple (Acer saccharinum). When eaten by horses, the wilted leaves of the red maple can lead to a severe and possibly fatal anemia. Since Autumn Blaze is a hybrid of the red maple, it is possible, although undocumented, that it may be toxic to horses. Be cautious and do not plant Autumn Blaze in or around a horse pasture where the horse could consume the wilted leaves. While it is better to limit access to problem trees, you should quickly clean up any branches that may be blown into a pasture after a storm or in the autumn when the leaves fall.