Who is cutting the tails off these horses?

Why Do They Cut Off Their Tails?

The Tale of a Draft Horse

I know it would be best if he were standing straight, but for a nice, 'full' tail to grow out, up to where would you cut it? Just the tips, or higher?

How To Clip A Horse's Tail, How to Shave a Horses Tail

Maintaining a Horse's Healthy Tail, 20 Tips from Cowboy Magic - Cowboy Magic

Who is cutting the tails off these horses?

Someone is Cutting Off the Tails of Horses in Colorado

Equine conformation - Wikipedia

Budweiser won't cut off the tails of its famous Clydesdale horses