A herbarium is a collection of preserved plants that are used for scientific study.
The specimens are typically dried and mounted on a sheet of paper, but the specimens may either be whole plants or plant parts.

Botany
Botany is the study of plants. Most specimens are preserved by pressing and drying the leaves, stems, roots, flowers, and fruit then affixing them to acid-free paper, along with their data label. Wood samples may be stored separately and fleshy fruits may need to be freeze-dried. Many of the 15,600 specimens in our collection were collected prior to 1900 in the Chicago Wilderness region but we also have specimens from Cuba, parts of Europe, and significant specimens from a U.S. Army expedition west of the 100th meridian. Prominent collectors include Herman S. Pepoon, Elizabeth E. Atwater, and Henry C. Cowles.