Appendix Quarter Horse Origin and Characteristics

For many breeding associations, horses that do not qualify for full registry for some reason, but do qualify because they are a member of that specific breed or another qualifying breed, can still be registered in an “appendix.” The appendix is a listing of horses that are not allowed to register for breeding rights, but may be able to do so in the future.

Within the pedigree of many Quarter Horses is a Thoroughbred bloodline. One of the most influential and popular horses in the Quarter Horse breed was named Three Bars and he was actually a Thoroughbred. Because of the definition of an Appendix Quarter Horse, it becomes possible to diversify and stabilize the genetic profile of a breed.

Appendix Quarter Horses are a little different, however, because they must meet a specific definition. To qualify for this classification, a foal must have one parent that is a purebred Thoroughbred and one parent that is a purebred Quarter Horse. An allowance is made for foals that have one parent in the appendix of the Quarter Horse stud book and the other parent is a Quarter Horse that has been granted a permanent registration number.

The Origin of the Appendix Quarter Horse

There are currently more than 4 million Quarter Horses currently registered. This includes those that are registered within the appendix.

By definition, an Appendix Quarter Horse is a first-generation offspring from a Thoroughbred and Quarter Horse or between a numbered Quarter Horse and an Appendix Quarter Horse. Thoroughbreds are allowed within the breed assuming they can meet performance standards. Then, should an Appendix horse meet specific conformational criteria and successfully race in sanctioned events, they can move out of the appendix and into the full registry.

This process allows for Thoroughbred bloodlines to continually improve the Quarter Horse breed. It also separates the appendix horses from the foundation horses that have set the standards for the Quarter Horse breed over the generations. 

Quarter Horses have been a component of American history since the late 17th century. English Thoroughbreds were imported to the colonies and then bred to local tribal horses, such as the Chickasaw. Since the “native” horses came from earlier arrivals or disposals from colonial fleets, the genetics included Arabian, Barb, and Iberian bloodlines.

Breeders noticed that the resulting combination tempered the hotblooded nature of the Thoroughbred, but retained the speed and strength of the horse. Quarter Horses got their name from their ability to run at speed over the distance of a quarter-mile. When flat racing became popular in the 19th century in the US, it was found that the Quarter Horse could outrun a Thoroughbred at that distance.

Some Quarter Horses have been found to run as fast as 55 miles per hour.

Homesteading required a steady and strong horse that had drafting characteristics as well. Many homesteaders who moved out West during the expansion era of the United States were far from wealthy. They could afford one or two horses at most, so they needed one that was versatile and durable. These characteristics were then bred into the Quarter Horse, creating the modern breed that we see today.

Many Appendix Quarter Horses share the same “sense” for working with cattle and livestock that their ancestors showed so long ago. Not only are they fast, but they compete well in rodeo events, and many are still used for ranch work in the US western states today. 

What Are the Characteristics of the Appendix Quarter Horse?

The Appendix Quarter Horse stands at 14.3 hands or higher. There is no maximum range that is currently in place for the breed in any of the associations that support these horses. Some can grow to be as tall as 17 hands, but most tend to top out at 16 hands.

Like their fully registered counterparts, Appendix Quarter Horses come with different body types. There is a racing-type horse and a stock-type horse. Stock horses tend to be a little shorter, have more muscle mass, be compact, but still have the agility that the Quarter Horse is famous for having. Racing horses tend to be a little taller, have a smoother muscle mass, and cleaner lines.

Appendix Quarter Horses that fit the racing-type profile tend to look like a modern Thoroughbred horse.

When compared to a fully registered Quarter Horse, an Appendix horse has a similar personality and the same versatility. These horses are steady, have an even disposition, and are usually easy keepers. They tend to be highly competitive, but enjoy working with others, and be social within their heard. Some may run a little “hot” in their personality, but this can be funneled into an activity, such as racing.

Virtually every color is possible within the breed. Most horses tend to follow the sorrel coloring that is dominant within the Thoroughbred, but there are black, brown, gray, buckskin, and palomino horses within the breed.

Pinto coloration is also possible, but the American Quarter Horse Association will not register horses with that coat. The American Appendix Horse Association will accept the registration, however, assuming there are Thoroughbred bloodlines present in the lineage of the horse.

How Can an Appendix Quarter Horse Become a “Full” Quarter Horse?

If a Quarter Horse is allowed to register in the appendix of the American Quarter Horse Association, then it has an opportunity to move out of the appendix and into the full registry over time. The horse earns this opportunity if it can earn at least 10 performance points within the show-ring, though halter events are excluded from points collection.

Horses in the appendix that have a speed index rating of 80 or higher on the racetrack may also qualify to move out of the appendix and into the full registry.

Breeders or owners of an appendix horse which meets those qualifications can apply for permanent papers for their Quarter Horse with the registry. The ability to qualify for the application does not guarantee that permanent status will be granted for the horse.

If the horse is permitted to move out of the appendix, its status changes. Although it may be an Appendix Quarter Horse by definition, it will be treated as a full Quarter Horse for breeding purposes. Assuming that breeding occurs with another registered Quarter Horse, the offspring would qualify for immediate registration with permanent status.

For horses that are not accepted or horses that may not have a proven lineage, the American Appendix Horse Association also contains a hardship clause. Foals can be registered with them if there is only one registered parent if the foal can meet specific performance and physical standards.

The Appendix Quarter Horse allows for all Quarter Horses to benefit from the rules of breeding so that performance, genetics, and physical traits can all be maintained or improved over time.