Appendix Quarter Horses: 9 Facts You May Not Realize Are True

Last Updated on February 24, 2022 by Allison Price

Most people don’t think about Quarter Horses when they think of them. The Quarter Horse should always be considered a Quarter Horse. This is true, but even purebred Quarter Horses are capable of being mainly thoroughbred. This is partly due to the Quarter Horse registry’s Appendix section.

What’s an appendix quarter-horse? A registered Quarter Horse crosses with a registered Thoroughbred Horse to produce a foal that is classified as an Appendix Quarter Horse.

This is because the foal will be registered as an “Appendix” foal. An Appendix Quarter Horse cannot be bred to regular registry Quarter Horses.

Let’s now learn a bit more about the Appendix Quarter Horse.9 Appendix Quarter Horses Facts You May Not Know Are True Play Video

1. Appendix horses have been around since 1949

According to the AQHA the Appendix horses were first registered in 1949, when the American Quarter Racing Association and National Quarter Horse Breeders association merged. All horses were then registered as Appendix, and horses were inspected to verify their permanent numbers. The appendix registry technically contained “purebred quarter horses”. Although the registry was just being created, the term “purebred”, could still be used loosely.

The Appendix registry was modified in 1962 to exclude foals that were born from a mixed Thoroughbred Thoroughbred and Quarter Horse. Since then, it has been this way. (source)

2. Appendix Horses Are Very Versatile

Appendix quarter horses are known for their versatility. They can excel in all disciplines if they are given the right training. These include, but are not limited to:

Halter

Western Pleasure
Hunter Under Saddle
Racing

Barrel Racing
Team Penning
Team Sorting

Jumping

3. Appendix Horses are Available in Every Color

Quarter horses are more limited in color than Thoroughbreds. The appendix quarter-horse can be any color that a regular quarter horse can. This happens because they are at most half quarter horse. While colors such as bay, chestnut and black are most common, it is possible to use dilute colors such as palomino and dun.

4. Appendix Horses Can Become “Regular” Quarter Horses

According to AQHA Rules, any Appendix-registered horse that earns 10 points during competition (a ROM), can be eligible for full papers. This means they have competed against other quarter horses and won. They are required to turn in their Appendix papers and receive regular papers. (source)

To earn their Register of Merit award, they can show in performance, racing or halter. To be eligible for the regular registry, they will need to meet additional requirements. Appendix horses may be advanced for as long as:

They don’t have parrot-mouthed mouths.
They are not cryptorchid.

They don’t have excessive white markings.
They are HYPP N/N

If all these conditions are met, the owner may pay a small fee to make the horse a regular quarter horse.

5. Quarter Horses are Mostly Thoroughbred

Yes, it sounds confusing. Let’s now follow Artful Move, the son of the World Champion stallion.

Artful Move was sired from Wind Chime, a Quarter Horse Stallion. His dam was Buzz Fly, a Thoroughbred mare. This made him half thoroughbred and half quarter horse.

Artful Move was awarded his ROM and more! He was promoted to the regular registry. He was bred many mares, including Elaine Myrna, a thoroughbred mare. She was the mother of Indian Artifacts. He was registered as a quarter-horse but 75% thoroughbred.

Indian Artifacts was initially registered appendix, but he ALSO received an ROM (and many other championships). He was eligible to be bred with thoroughbred mares because he had his regular registry papers. He was able to bred his foals to thoroughbred mares because he had received his regular registry papers.

As long as the foals receive a ROM, they can be continued for many generations.

6. Some Appendix horses are mostly Thoroughbred

Just because an Appendix quarter horse is purchased does not necessarily mean that the horse is half thoroughbred. Let me explain.

Similar to the example I gave above, in which I demonstrated how a Quarter Horse could actually be mostly thoroughbred; an opposite example can illustrate how an appendix horse can also be mostly Quarter Horse.

Let’s suppose a Quarter Horse is bred with a Thoroughbred, and the foal is registered Appendix. Even if the horse doesn’t earn their ROM they can still have registered babies. They can still be registered quarter horses if they are bred to regular registry quarter horses.

We might choose a horse that is 50% Thoroughbred, 50% Quarter Horse. If she is bred to a 100% foundation Quarter Horse (no thoroughbred), then the foal will have 75% Quarter Horse blood, but is still registered as an Appendix.

A foal that does not receive a ROM can still be bred. However, they must be bred to a regular Registry Quarter Horse. The foal will now be 87.5% Quarter Horse.

If the foals do not earn enough points to be eligible for the regular registry, this could continue for many generations. An Appendix-registered horse that is more than 90% Quarter Horse could be

7. Appendix Horses Can Be Super Tall

Although 16 hands are not uncommon and 17 hands are not unusual in Quarter Horse breeds, some horses can grow even taller. Quarter Horse stallion The Game Changer is 18 hands tall. He is 50% Quarter Horse, 50% Thoroughbred. You can see his height at the withers in the horse height chart. This horse is quite tall!

8. Appendix Horses can be short

One misconception about Appendix horses, is that they are all too tall due to their being part thoroughbred. Some Appendix horses can reach heights of 17 hands or more, but they are also very tall. You could see an Appendix horse with 14.2 hands or less.

9. Appendix Horses can produce registered warmbloods

That is probably what you are thinking. Although a Quarter Horse can be considered a warmblood horse, there are not enough warmblood registries to permit a Quarter Horse to be registered. However, this is not the case. Quarter Horse stallions have been approved for breeding by the American Warmblood Registry (AWR). Indian Artifacts was approved for this registry as a stallion.

The Quarter Horse stallion My Rugged Destiny is on the approved stallions list. He’s a son Rugged Lark. Rugged Lark was a 1/2 Thoroughbred, which makes Rugged Destiny a 1/4 Thoroughbred. Both horses are registered in Quarter Horse Registry, but Rugged Lark is a show champion who was able to move up to regular registration.