Herbarium specimens are used to identify, classify and name plants, algae and fungi. The information recorded at the time they were collected provides a permanent record of when and where different species have grown, as well as information on the environment they were growing in.
Sometimes, herbarium specimens are the only remaining examples of a species. This specimen of Senecio georgianus was collected by Ferdinand Mueller in Omeo in 1854. This species is known only from a few herbarium specimens collected in the 1800s, and is now presumed to be extinct in Victoria and other states.
Collectors often gather material for more than one preserved specimen to exchange with other herbaria. These ‘duplicates’ provide herbaria with vital reference material, as well as acting as an insurance policy against damage to the original. This specimen of Zollernia falcata collected in Brazil is a great example – it is a duplicate of a specimen from Berlin was destroyed in WWII.
When a new species is described and named, its name is permanently linked to a preserved specimen, which becomes the 'type' of that name. The type specimen acts as a global reference point for how that name should be used. The Herbarium holds thousands of types of Australian plants thanks to Ferdinand Mueller’s untiring research on the Australian flora.
As scientific methods evolve, so do plant collection and curation methods. Where possible, RBGV botanists collect extra plant material that can be sampled for molecular analysis – or DNA sampling – to help elucidate the relationships between plants. These samples are stored in silica gel and kept frozen until needed.