It's that time of year where in all the pretty pictures of Autumn Foliage in New England the Maple tree takes center stage. Everyone is sharing photos of lovely landscapes, children playing, dogs romping, Horses grazing, lovers strolling, all amongst the colorful foliage of one our most prolific deciduous trees. The Maple leaves are magnificent. Filling or lenses with vivid crimsons, fiery oranges, and yellows so bright they seems to create their own luminescence.
It's a gorgeous time of year to be out and about enjoying the weather and the beauty of this season. But if you have horses and or friends who do the spledour of the Red Maple defoliating brings up a most disturbing topic. The deadly threat of its wilting leaves to horses who might graze on them. We've all heard that the Red Maple leaves can kill horses if eaten wilted. But other details become clouded with hearsay and superstition and so many horse owners having differring stories to tell of the experiences they have had. We must revisit all the details as best we can to convince ourselves once again that we have not put out horses at risk. One of the major sticking points is: how does one define "wilting" anyway?
My veterinarian told me that it is a very specific condition of the leaf, a chemical reaction that happens within a living leaf when the branch that the leaf is attached to is cut or broken from the tree, and the leaf subsequently begins to die. This chemical causes a reaction in the horses blood creating Hemolytic Disease . Oxygen is removed from the blood and death is imminent in many cases. She told me that leaves turning color in the fall and falling to the ground do not create a hazard in New England.
Here is a Good resourse of information on Hemolytic Disease and Maple identification. (just click on the colored text)
Armed with this information I do not worry over the brightly colored leave that carpet the paddocks this time of year--UNLESS a storm should knock down a Maple or brake a branch from one. I always remove the felled maple and any broken branches from the horses reach. We did some amount of pruning on some of our Sugar Maples in the yard this summer. I was very careful to remove the prunings all branches and leaves.