Herbaria

Herbaria are organized repositories of preserved plant specimens and their associated data, used for scientific study, education, and conservation. Most specimens are dried, pressed plants mounted on sheets, with labels recording the scientific name, locality, date of collection, habitat, collector, and method of determination. In addition to vascular plants, many herbaria hold bryophytes, lichens, algae, and fungi, depending on their scope.

The practice developed during the early modern period and expanded through the 18th and 19th centuries as explorers circulated collections. Major national and university herbaria—such as those at Kew, the Muséum national d’Histoire naturelle (Paris), and other large institutions—built extensive holdings. Index Herbariorum, a collaborative directory, lists active herbaria and their curators, facilitating collaboration and access.

Preparation and data management involve pressing and drying specimens, mounting them on sheets, and assigning a unique accession number. Labels provide collection details and often the determiner’s name. Specimens may include reproductive structures, seeds, or tissue suitable for future analyses. Type specimens (holotypes, lectotypes) anchor species names and are accorded special importance.

Storage and curation require climate-controlled rooms and organized cabinet systems to protect delicate plant material. Pest management, regular maintenance, and careful handling preserve specimens for long-term use. Many holdings are accessible through loans to researchers, and increasing digitization projects produce high-resolution images and metadata for online catalogs and virtual herbaria.

Uses of herbaria include supporting taxonomy, floristics, biogeography, ecology, and conservation planning by providing verifiable reference material, distribution data, and historical baselines. They also enable phenological studies and, with modern methods, genetic analysis from historic material. Global networks and databases enhance discoverability and data sharing among researchers.