Protecting Biological Heritage:
Making and Preserving Plant Specimens (18 min.) Producers: Lyndon Wester and Steve Meyer
Department of Geography, University of Hawaii
CTAHR Video Production Facility, Honolulu, HI
Documenting your
Specmen Collection Voucher specimens are also known as herbarium specimens
or simply as vouchers. These specimens document research studies and enable you
and other scientists to determine what kind of plants were studied, where they were found, who identified the plant, and
what they are named.
Specimens are
simple to prepare. With proper techniques you can preserve your research
for a very long time. Specimens made over 400 years ago are still being
studied today. Once deposited in a herbaria, your specimen can become
part of a larger collection and many other researchers can benefit from utilizing your specimens.
Voucher specimens
also provide your research study with detailed data, reproduceability,
and a permanent record of your work. What species was found at a particular
location, in a particular habitat, at a specific time or date.
Research
that is supported by the collection of specimens should include a statement
stating which Herbaria and location the specimens were deposited. A global Herbaria Index or directory is available online. There are more than 3,350 herbaria in 168 countries. There are 10 herbaria in the state of Hawaii.
There are 7 basic steps to making a specimen;
1. Preparation If properly prepared, field collecting plants is very easy.
You will need some simple tools prior to beginning collecting the local flora. Plant presses are all available in the herbarium drying room (St. John 404).
2. Specimen Collecting & Recording Fieldnotes
A small pair of clippers, and trowel will make it easy to collect a plant specimen with either intact roots or a clean cut from a branch. If the plant is a small herb, collect the whole plant including the roots, remove loose soil
as mush as possible.
Use plastic bags to store the specimens until they are placed into a plant press. Once you have collected your specimens, they should be placed in a plant press to flatten the specimens and dry them out. Plant pressing can be done at home, or the Botany laboratory but preferably is done in the field, where your plant is still fresh and your plant collection information is still fresh in your mind. In your field notebook, you should record all collection information with the help of your plant guide to tentatively identify your plants.
It is important to record the following essential data in your field notebook.
Plant common name (if known)
Family, Genus and species
(if known)
Collector name(s)
Collection number (assigned by collector)
Date of collection
Collection locality (include country, state, city, island and all precise location data)
3. Pressing and Drying
Pressing your plants has several purposes. The most important reason is to rid the specimen of all excess moisture, so that the specimen will not mold or rot. Another reason is that pressed plants are easy to mount on herbarium paper and the plant parts will not stick out, leaving them vulnerable to breakage.
Place your plant press in the dryer in room 404. Clearly label your plant press with your name and date. Drying normally takes up to 5 days depending on what type of plants and plant parts you collected.
4. Making Specimen Labels - Online Data Entry
While your plants are drying, you can prepare your specimen labels and enter your field data in the standardized herbarium data base and label maker via the Internet. Students must create a username and password to access the resource. Click here to register...
5. Mounting, and Labelling
Mounting requires several materials including cardboard, mounting poaper, wax paper, and weights.
Proof your label for correct taxonomy and mispellings before applying it the the specimen. You can paperclip your label to the specimen temporarily.
Use a recommended adhesive (white PVA resin, plasticized, water soluble adhesive) like Elmer's glue (not rubber cement) and ALWAYS mount the specimen label in the lower right corner.
6. Specimen Freezing and Depositing into the Herbarium Collection
Contact the Collection Manager prior to bringing specimens into the herbarium. All specimens MUST BE FROZEN for 5 days before completing the specimens accessioning and filing. This quarantine procedure reduces the potential of insect pest introduction.
7. Specimen Imaging and Digitization
Well documented specimens may be digitally scanned to provide a complimentary image of the specimen record in the Herbarium collection catalog. Scanning a specimen is an easy procedure taking about 3 minutes per specimen. Specimens are scanned at 600 dpi, using an Epson GT-15000 flatbed scanner. Specimens can also be imaged using digital camera that is available in the herbarium.
Related Publications Bye,
R. A. 1986. Voucher Specimens in Ethnobiological Studies and Publications.
Journal of Ethnobiology, Society for Ethnobiology. 6(1):1-8.
Womersley,
J. S. 1976. Plant Collecting for Anthropologists Geographers and Ecologists
in New Guinea. Botany Bulletin No. 2. Department of Forests, Port Moresby,
Papua New Guinea.
Smith,
C. Earle. 1971. Preparing Herbarium Specimens of Vascular Plants. Agriculture
Information Bulletin No. 348. Agricultural Research Service. USDA.