The Bessey Herbarium was founded in 1874, making it among the oldest in the Great Plains states of Colorado, Kansas, Montana, North Dakota, and Nebraska. The collection has more than 310,000 specimens, placing it among the largest in the Great Plains. The largest parts of the collection are, in descending order, from Nebraska, the Great Plains, the Rocky Mountains, other parts of North America, and Europe. It contains important collections by such scientifically notable Nebraskans as Charles Bessey, Ernst Bessey, Frederic Clements, Walter Kiener, Per Rydberg, Raymond Pool, Jared G. Smith; by other Nebraskans who later became prominent in other fields, such as Roscoe Pound (Law), Louise Pound (Literature), Willa Cather (Literature), Melvin Gilmore (Ethnobotany), Lawrence Bruner (Entomology) and Henry Baldwin Ward (Parasitology); and by many prominent scientists from outside the state.