When did they get into docking tail other than for show? I have reviewed a lot of my family pictures from around the 30s and 40s and nearly all of the teams they used had long tails and thse were all farming horses, no show .

I suspect docking was regional. Purpose was to keep the tails from getting caught in machinery. I greatly oppose the practice for horses.

My take on it is just from observation and thought on the matter. Not all horsemen have the tradition, and others have stopped following it. I happen to fall into the latter category.

Tails were docked by some cultures on Draft horses from very early days, using the rationale that long tails can interfere with driving lines, primarily. Secondly, they can be a chore to keep clean sometimes, which takes time.

The show horses in big hitches especially continue with the tradition of docked tails more out of form than substance, I think, and it's only, or mostly, in the US. Europeans have banned the cutting of tails, and braid them instead. Some states in the US have banned docking as well.

I used to cut, but no more.

Registered Draft stock from Europe was docked

In a very general way, I believe you'll find that was more common in certain areas of the country, especially New England up through the 19th c. until the first animal welfare groups tried to put a stop to it in the 1870s.

Horses were docked for practical and aesthetic reasons, for the former so that horses couldn't catch lines with switching tails and for the latter so that their rear ends would be more visible and therefore appear to be bigger. Where I am from, in Bavaria, farmers always liked to have long bushy tails on their horses and on festive occasions even braided strands of flax into them just like into the manes to make them look bigger. Ironically, in Germany the docking of horses' tails was first prohibited during the Third Reich for humane reasons by exactly the same people who were immensely cruel to everyone they considered "un-German".
I think Thomas is right and to my knowledge most European countries have outlawed the practice of docking horse's tails.

Not taught in any Veterinary School/College in the US.

I never saw the sense in it for anything other than looks. It does make the muscling in the rear look bigger. I don't think it's at all necessary for safety. You can braid the tail up or bag it if you have a problem with tails in lines, or better, re-rig the lines. Same thing goes for docked tails on dogs or cut ears. Why?

I believe it is illegal here in france

You can trim a horses tail To hock length. The old timers would tie the tailes with binder twine along the belt.

Pictures of Grandpa's teams from the '20s and 30s in Iowa show the tails hock length. I had a couple different mares with long tails and more than once had them over the lines, vanity kept me from cutting the tails off at the hocks. Coon dogs tails are docked to keep the coons from grabbing the dogs tails.

Since the response regarding dogs seems to have begun......... there is no reason to tail dock or ear crop for any breed of dog. People seem to keep coming up with their "logical" reasons, but ask the dog if it wants it's tail cut off or it's ears mutilated. I actually have a person in town with a boxer who claims it's tail is docked because they are so happy they wag their tails and hit furniture in the house, traumatizing the tail and making it bleed.

You would dock your dogs tail if you worked him in a feedlot where he would get covered with manure and he had to ride in the cab of your vehicle.

Circumcision is something I wouldn't have come up with on my own either.

Mutilation is weird and gross, but common among two-leggeds.

I've often wondered how big does big have to be? Since when does the butt of a 1800 pound horse NOT look big? Another reason to like a Suffolk Punch. Don't change a thing is the breed motto. Gotta admire that.