Bison Wool Fiber Characteristics

Ann Braaten, Senior Lecturer, Apparel, Textiles & Interior Design, 
Robyne Williams, Assistant Professor, Apparel, Textiles & Interior Design
North Dakota State University, Fargo

Bison are molting animals which shed their coats in the spring of each year.  Native Americans have used the fiber for rope, stuffing for insulation, and fiber art.  This textile fiber source can be utilized to add value to animals raised for breeding and for slaughter.

While bison wool fiber has been used for textile products, its textile properties are beginning to be understood.  So far, the fineness of the fiber has been measured, fibers have been microscopically analyzed and photographed, and the moisture regain of the fiber has been measured.

Fiber from two female bison was analyzed, one animal was considered to be dominant and the other subordinate in the herd (Miller, B.). In space restrictive environments, animals very low in rank show an inhibited feeding behavior, resulting in a diminished nutrient intake (Calhoune, J.B.).  In sheep, a low nutrient intake can decrease fiber diameter, making the fiber softer and more comfortable.

Bison fiber is made up of course guard hairs and fine downy hairs.  The guard hairs are hollow and range from 21 to 110 microns in diameter, with an average 59.0 microns (this is similar to course human hair).  The fine downy hairs are solid and are covered with fine scales.  Downy fibers range in diameter from 12 to 29 microns.

Dominant animals downy fiber averaged 21.8 microns and subordinate animal averaged 18.8 microns.   Both types of fiber were consistent in size from the root. The fiber diameter of downy bison fiber is similar to sheep's wool in the fine and medium grades.

Moisture regain of bison wool ranged from 13 to 20 percent.  This is a broader range than that of sheep's wool, which ranges from 14 to 16 percent.  Moisture regain is a measure of the amount of moisture a fiber will hold without feeling wet and is used to understand the comfort level of a fiber.  The more moisture a fiber will hold, the more comfortable it is to wear. 

This information will help to determine marketing strategies and potential end-uses of the bison wool fiber.  If the course hairs are separated from the fine hairs, the fine hairs can be sold as a high quality, high price product.  If the two fiber types are left together when used, a rougher product results. .  If a fine quality, and high priced bison fiber is desired, steps must be taken to market this type of bison fiber in a different manner than the courser mixed fiber.

Currently, U.S. law gives the Federal Trade Commission power to control which fibers can be called wool, and bison fiber is not included on their list.  The Consumer Protection: Product and Services Code: Chap. 2, Sec. 68(b) defines the term ''wool'' as fiber from the fleece of the sheep or lamb or hair of the angora or cashmere goat (and may include the so-called specialty fibers from the hair of the camel, alpaca, llama, and vicuna) which has never been reclaimed from any woven or felted wool product (  This needs to be broadened to include the wool of bison.

Given the mythology associated with the American bison and the romance of the Old West, the potential for development of bison wool as a textile material and value-added product exists.  It is up to bison producers to decide how to utilize this resource.

Calhoune, J.B. 1963. The Ecology and Sociology of the Norway Rat, cited in Animal Populations In Relation to Their Food Resources. 1970.  Adam Watson, Ed., Blackwell Scientific Publications, Ltd. Great Britain. p. 188.

Giest, V. 1996. Buffalo Nation: History and Legend of the North American Bison.  Voyageur Press, Inc.  Stillwater, Minn. p. 107.

McHugh, T. 1958.  Social Behavior of the American Buffalo (Bison bison bison). Zoologica, 43, pt.1, 1, 17 - 23 (March 31, 1958). Included in Social Hierarchy and Dominance. 1975.  Martin W. Schein, ed.  Benchmarck Papers in Animal Behavior V. 3, Dowden, Huchinson & Ross, Inc.

Miller, B.  May 6, 1996.  Personal Communication.

Sheep Industry Association. 1996.  Sheep Producers Handbook.  p. 656.

NDSU Vice President,
Dean and Director for Agricultural Affairs
NDSU Extension Service ND Agricultural
Experiment Station
NDSU College of Agriculture NDSU College of Human Development and Education