Utahs Native Horses
DUN-FACTOR HORSES
The primitive striped Sulphur Horse of Utah is a unique breed of horse, the dun-factor horse and others populated the desert Southwest. These Horses have dun (grullo) color, had a "sooty" face, i.e. dark muzzle area, lower leg striping and a dorsal stripe. Foals are often born with zebra stripes all over the neck, back and rump, with the Sulphur Horses these stripes still remain even in mature horses. The ears are black-rimmed and have a dark upper portion on their backside. The head may show "cob-webbing" on the forehead. Mane and tail are bi-colored, i.e. the dark hair is flanked on both sides by light-blonde colored, often almost white, hair. This same "white" coloring can also be on the horses ankles, sometimes referred to as "feathers". Another characteristic is the barring on the neck, sometimes extending from the underside of the neck or chest. This is not caused by a darker color, but rather by a different grain of the hair coat, and is more or less visible depending on how the light is reflected and how long the hair is.
The most common Dun Factor is the DORSAL STRIPE. This stripe usually runs from the top of the mane, along the horse’s spine, into the tail. Some Dun Factor horses have stripes go through their private parts, on their under belly and finally ends on the chest and under the neck.
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The BODY of your GRULLO (male) or GRULLA (female) horse will be light gray but the Dun Factor marking will be really dark gray, like the color of charcoal. The base color of the mane of the horse must be darker for the horse to be considered a true dun. The markings are darker than the body color and most often the same color as the mane/tail. Some horses have a Tri-colored mane, with blonde, white or really light gray hair.
Cubel Ranch was lucky to have a "Royal Family", these three full Sulphur Horses had an over abundance of the Dun Factor. Daughter: Honey, her mom, Cielo aka CLO and the daddy Sulphur Prince.
Dun Factor horses are different than a Dun colored horse, such as a Buckskin. The Buckskin horses have a black dorsal stripe and black on their legs, usually from their ankles up to their knees, but do not have the Primitive Dun Factor markings.
The Sulphur Herd roams a vast, unpopulated region of alternating high desert basins and expansive mountain ranges. Their home, the Needle Range, is a starkly beautiful mountain block that lies about 45 miles west of Milford, Utah, along the Nevada State line. In some areas, the range rises to nearly 10,000 feet in elevation. from north to south, the mountainous spine of the Needle Range is comprised of two main peaks - Mountain Home and Indian Peaks.
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Ranchers nearby knew of these Utah Native born Horses and at one point during the 1950’s tried to get the Sulphurs to breed up in size with their domestic stock. The Sulphur Horses segregated themselves and moved further up the mountain, away from these ranch horses, keeping the herd true with old native born traits.
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Native Horse populations can provide valuable information about current levels of genetic variation". Genetic analysis can be a useful tool in the overall management of Native born Horses populations on public lands.