In 2008, there were about 3.5 million kindergarten, elementary, middle and high school teachers in the country, so we can expect almost another 500,000 to be hired by 2018. Also indicative of the high demand for teachers is the large volume of grants available for teachers.
Another option is to mix small amounts of apple cider vinegar with the animal's drinking water; consuming this solution is known to change the blood pH of the horse, thus keeping horseflies away. Cider vinegar, coupled with essential oils, is also used in home sprays as the sharp odor may repeal horseflies.
Use vinegar as a natural fly spray for your horse. You can use 2 cups of vinegar with 1 cup of water and 1 cup of Avon Skin So Soft bath oil mixed with 1 tbsp. of Eucalyptus oil. You can also add a tbsp. or two of citronella oil to this mixture. Shake it well and then spray on your horse.