Fly Swatter

A horses tail is very effective at chasing away flying insects. And, the longer and the heavier, the better!

I've heard it said that in years past, when a horse owner wanted to pasture his horse on another's field, the owner paid rent proportional to the length and weight of the horse's tail. Shorter tails paid less rent. The point being that the long-tailed horse would be less distracted by flies and able to eat a larger share of the grass.