The Intermountain Herbarium was founded by Bassett Maguire in 1932. Taxonomy had been taught at the Utah Agricultural College before that time, using a collection of about 90 plants that had been provided by C.V. Piper, a botanist who developed the first floras for the Pacific Northwest and went on to work on the introduction and domestication of grasses for the USDA.
In 1932, Maguire persuaded the Utah Department of Agriculture and the Utah Agriculture Experiment Station stating that "Since the knowledge of the composition, and particularly the distribution, of our flora is inadequately known, and since such data are essential to proper administrative policies concerning state lands and to technical research which is fundamental to all agronomic activities, the immediate program of the herbarium shall consist of a preliminary plant survey of Utah".
When he filed the herbarium’s first annual report in June 1932, Maguire had assembled 10,432 specimens of which 5,682 had been mounted and filed prior to receiving official approval for the project. During the herbarium's first year as UAES Project 135, an additional 3,479 specimens were collected of which 2,147 had been mounted and incorporated into the collection. In 1943, Maguire went to the New York Botanical Garden to work on Utah plants. He eventually ended up staying there, becoming its director and developing a research program focused on Central andSouth America.
In 1948, Maguire was succeeded at the Intermountain Herbarium by one of his students, Arthur H. Holmgren, who remained in charge of the herbarium until his retirement in 1979. Holmgren carried on Maguire’s floristic emphasis, adding to the collection and preparing various publications on Utah’s plants.
In 1963, a staff position was add to the herbarium. This was first held by Bernice Anderson who worked with Holmgren on several popular publications on Utah’s plants. She was succeeded by Leila Shultz who conducted floristic research in the region and, after completing her doctorate, joined the College of Natural Resources as a research faculty member. The position is now held by Michael Piep.
Holmgren was initially succeeded by Barkworth but she was replaced by Richard J Shaw for a few years. During his tenure, Shaw completed work on his Vascular Plants of Northern Utah, a work that was used for almost 30 years in plant taxonomy classes at U.S.U. in addition to revising his checklists for Yellowstone and Grand Teton National Parks. After Shaw’s retirement, Barkworth was reinstated as the Director of the Herbarium. Since her reappointment, one of her primary goals has been making the herbarium's resources and botanical knowledge more accessible. She is ably assisted in this respect by Michael Piep, the Assistant Curator since 2004, who draws on the knowledge and experience he gained as a botanical consultant, teacher, and mycologist in presenting talks and workshops as well as in identifying plants. Last year he added to these accomplishments by arranging a highly discounted price for some display cases – and then raising the money needed to purchase and refurbish them. With these cases, the herbarium will, we hope, succeed in attracting a more people to the fascinating world of plants and fungi.
The herbarium is particularly rich in grasses and literature about grasses. This started with Holmgren’s interest in the group but its recent development reflects Barkworth’s research interests and her role as both scientific and managing editor of the two grass volumes in the Flora of North America series. The herbarium served as both the editorial and production center for these two volumes. The materials provided were then used to develop two other publications, Manual of the Grasses of North America and Intermountain Grasses. Royalties from these publications have been critical to the herbarium’s subsequent development.