Trying to get tree sap out of your horse's mane, tail and coat is like trying to peel gum off the bottom of your shoe—difficult, messy and time consuming. Here are some home remedies that might make the job easier:
Smear butter, mayonnaise or peanut butter on the sap and rub it in. Leave the foodstuff in place for a day to allow the oils to break down the sap. Then wash the area clean using shampoo to remove the greasy residue, which can attract dust.
Mechanic's hand cleaners are formulated to remove oil and grease from a person's skin. Most are very mild and can be used sparingly on a horse's skin without irritation. Rub in a small amount until the sap loosens, then rinse thoroughly.
Rubbing alcohol or an alcohol-based hand sanitizer gel are a gentler alternative to harsher alcohol products used to remove saps from cars and fabrics. Place the cleanser on a towel and wipe the horse's coat until the sap has dissolved. Rinse as needed to remove any residue.