Herbarium specimens comprise pressed and dried plant material and associated collecting notes. When a new specimen is accessioned into a herbarium, it is first mounted. Mounting involves securing the pressed plant material and label to a sheet of card or enclosing it in a packet. Mounting allows specimens to be handled easily, protects specimens against damage and ensures that the label and plant remain together.
At the National Herbarium of Victoria (MEL), flowering plants, macroalgae, gymnosperms (conifers and allies) and pteridophytes (ferns and allies) are secured to Half Demy sized archival card (approximately A3 size). Fungi, lichens, microalgae and bryophytes (mosses, liverworts and hornworts) are placed in packets. Large or bulky specimens are stored in boxes.
Herbarium specimens are the scientific tools of botanists working in the fields of taxonomy, systematics, conservation and horticultural botany. When specimens are mounted, careful attention is necessary to ensure that important diagnostic botanical features are preserved for long-term scientific use. For example, material needs to be arranged on the sheet so that botanists can easily examine flowers and other key features under a microscope.
At MEL, mounting and other curatorial work is carried out by skilled volunteers and curation staff. A team of approximately 40 volunteers mounts more than 17,000 specimens per year.
Well-mounted herbarium specimens can last for many centuries. At MEL, all materials for specimen mounting are of archival quality: all paper, card and glues are acid-free and remain stable over time.
We use four methods to secure a specimen to a mounting card:
- spot glue with PVA
- paper strip with gummed paper
- sew with needle and thread, securing knots with linen tape
- float specimens on to card (in the case of macroalgae).
The physical features of a specimen determine the best method for mounting it. Some specimens require a combination of all three methods. It can take a skilled mounter anywhere between ten minutes and half an hour to mount a specimen.
Once mounted, each specimen is placed in a paper folder and the family name, taxon name and collecting location are recorded on the front. This information ensures that material can be accurately filed in the collection. Specimens are databased before being filed.
Herbarium volunteers have helped us to mount MEL's entire Australian collection, which comprises over 800,000 specimens. We are now working our way through MEL's foreign collection of approximately 400,000 specimens, many of which have remained untouched since 1883, when Ferdinand von Mueller acquired the private herbarium of Otto Sonder. Mounting this material makes it accessible to botanists and other researchers and enables us to fully realise the international significance of the MEL collection.
Please see Volunteering at the Royal Botanic Gardens for information on volunteer opportunities.
Albrecht, D. (1993). Collecting and preserving herbarium specimens. National Herbarium of Victoria, South Yarra.