Facts and Figures

Scientific management

The herbaria and library of the BGBM provide close to ideal conditions for the botanical management of the live collections. A technical assistant is in charge of collecting, preparing and labelling specimens. Most of the identifications and verifications are made by currently 3 (in the past by up to 5) botanists. This situation is probably unique in Germany, and most favourable when compared with other botanical gardens.

During the past 20 years, 3 to 5 curators have worked steadily and intensively, while of course by no means exclusively, at the specimen-based taxonomic revision of the live collections. Every year, 800 to 1000+ accessions were checked as to identity. This effort, while time-consuming, is essential in view of the high general misidentification rate one finds in garden collections (see the following tables).

Average change rates upon verification, in the live collections 1976-1997

Average change rates upon verification, in the live collections  2001–July 2005

The ongoing revision process (which so far has involved about one half of all accessions) is essential if a high scientific standard is to be maintained. Verification of taxonomic identity and naming is a prerequisite for correct labelling - which is probably, however, an unattainable goal in most botanical gardens.

Usually in parallel with accession verification, correct species-based information for labelling (German and scientific name, author citation, distribution range) is being provided. Curators from other departments may contribute to this process, e.g. in the course of re-labelling of whole garden sections, particular collections or systematic groups (e.g., medicinal plant section, bromeliad house, tropical crop plants).

Since 1979, when a new accession numbering system was introduced, it was the Garden's declared policy to renew the live collections by well-documented accessions and plants grown from material collected in the field or its progeny. This new policy also influenced the Garden Herbarium, in which the number and quality of voucher specimens significantly increased, much to the benefit of taxonomic research and teaching. The garden reference collection is still maintained separately but contiguous to the respective family in the general herbarium, and includes many taxa missing in the latter. The Garden Herbarium - the largest of its kind in Germany and perhaps in Europe - is the basic tool for the botanical management of the live collection. It greatly enhances the routinely process of verification and identification. The consistent documentation of each verified accession by a voucher enables later re-examination, e.g. to trace the source of name changes due to re-identification.

Growth rate of the Garden Herbarium
(the current numbering system started in 1974)
Total, including pre-1974 post-war collections, c. 56,000 specimens.

The two following tables indicate the numbers of species and accessions held in the live collections as by the end of 1996.

Taxa, on species level:

Accessions (individual plant collections):

The ongoing process of data incorporation on all levels (accessions, garden location data, taxon based information) in the only recently modified electronic BoGART database will eventually provide the opportunity to update the above figures.

[Authors: B. Leuenberger and Th. Raus]

Index Seminum deutsch /English