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University of Wyoming

The Rocky Mountain Herbarium


The Rocky Mountain Herbarium (brief history) was founded by Aven Nelson in 1893 based on a core of specimens collected by B. C. Buffum and exhibited that summer at the Chicago World's Fair. Subsequent curators were C. L. Porter and John R. Reeder, ably assisted by his wife Charlotte Goodding Reeder. Ronald L. Hartman became curator in 1977. B. E. Nelson has been the herbarium manager since 1974. Located on the third floor of the Aven Nelson Memorial Building, the herbarium (definition) contains the largest collection of Rocky Mountain plants and fungi in existence. Additionally, there is a good representation of the floras of other parts of the Northern Hemisphere. It ranks 17th in the nation with 825,000 accessions and is the largest facility of its kind between St. Louis, Missouri, and Berkeley, California.


The primary functions of the Rocky Mountain Herbarium are:

• Education of students in systematics, ecology, and the biological sciences in general. The herbarium is used extensively by upper-division undergraduates and graduate students involved in a variety of projects. Additionally, specimens are used to demonstrate the diversity of plant life worldwide in the teaching of courses, especially plant taxonomy. Likewise, material is placed on display for organized tours by public school and university classes and other interested groups.

• Research in floristic, systematic, and evolutionary botany. The past 31 years has seen a significant resurgence in inventorying the flora of the region. This is especially true for species of conservation concern. Furthermore, staff and associates are involved in three main areas of research. First, systematic and evolutionary studies of genera in the families Apiaceae (wild carrots; Hartman), Asteraceae (sunflowers; Brown, Hartman), Bromeliaceae (pineapples; Brown), Caryophyllaceae (chickweeds; Hartman), and Salicaceae (willows; Dorn). This includes the description of species new to science. Second, the writing of books or taxonomic treatments for volumes on the plants of the Black Hills (Dorn), San Juan Basin (Hartman), California (Brown, Hartman), the Chihuahuan Desert (Hartman), Flora of North America (Brown, Hartman), Medicine Bow Mountains (Nelson), Missouri (Hartman), the Rocky Mountains (proposed), and Wyoming (Dorn). Third, the publication of biographies (Williams) of Rocky Mountain botanists Aven Nelson and G. E. Osterhout, and French botanists Louis Gérard and J.-H. Jaume Saint-Hilaire and the letters of Dominique Chaix, as well as early botanical history of exploration of the Rockies.

• Service to the lay and professional communities. Often this is in the form of identifying, or verifying the determinations of, plants collected in the region or elsewhere submitted by ranchers, farmers, and other citizens, state and federal agencies, and academics. We fill numerous requests for information concerning the native flora, introduced weeds and poisonous plants, and species of conservation concern.

The Rocky Mountain Herbarium (RM is the acronym) also includes the National Herbarium (USFS) of the U. S. Forest Service and the Wilhelm G. Solheim Mycological Herbarium (RMS). Thousands of specimens are loaned each year to recognized institutions throughout the world whose researchers require a knowledge of western North American plants.

Open to qualified students and researchers, the herbarium invites queries regarding the identification of plants. Persons wishing assistance in identifications should send a duplicate specimen of each plant to the herbarium with information about the date, habitat, and location where collected. The duplicate set of specimens often is a valuable addition to the herbarium. Following is a concise guide to collecting and preserving plant specimens and floras for use in the identification of plants in Wyoming and the region.

The Rocky Mountain Herbarium Library is an official non-circulating branch of the University of Wyoming Libraries. It contains an excellent collection of systematics literature for North America and major floristics and systematics treatments for the world.