A pressed, dried blue oak from the Oakmead herbarium
The Jasper Ridge Biological Preserve Oakmead Herbarium (JROH) is an essential research library conserving specimens of over 1,000 plants and lichens
The earliest vouchers date from the 1860s and were originally part of Volney Rattan's herbarium.
Collections
Collections are now fully digitized and hosted on the Consortium of California Herbaria!
Search by taxon, date, collector, and other criteria using Advanced Search
Over the intervening 150 years numerous workers have cumulatively recorded the following:
Tiger lily on trail 1. Photo by Alice Cummings
Moss in buckeye alley along trail 9. Photo by Alice Cummings
Gold-eye lichen. Photo by Alice Cummings
Herbarium specimens are dried, pressed plants or lichens.
Specimens, or vouchers, provide evidence of a plant's presence at the location and date documented by the collector on the specimen label. Other information on the label may include habitat, plant traits like flower color and abundance, and a list of associated species. Roots, fruits, seeds, and other tissues may also be mounted on specimens.
Vouchers provide morphological, DNA, and other data used for new, ongoing, and long-term research, including:
- conservation
- taxonomy
- phylogenetics
- population genetics/genomics
- ecology
- seed germination
- ethnobotany
All 5300 specimens were collected from the approximate 1200 acres now comprising JRBP ('O'O). Vascular plants in the herbarium represent over 10% of the terminal taxa (species, subspecies, varieties) native or naturalized in California, totaling 440 genera in 103 families, making Jasper Ridge one of the most botanically rich areas in the State. There are other measures of the richness of the Preserve's flora: Locally Rare and Uncommon Plants
Other collections made at Jasper Ridge are now housed at the Cal Academy of Sciences, after a 1976 merger of the Dudley Herbarium with its 850,000 specimen collection. The history of the herbarium is described by Jewett (2005) Documenting Plant Diversity: Jasper Ridge's Herbarium. For Stanford's rich botany heritage see Timby (1998) The Dudley Herbarium: its origin, fate, and legacy at Stanford
Vascular plants in the herbarium represent over 10% of the terminal taxa (species, subspecies, varieties)
What is an Herbarium?
An herbarium is analogous to a library, but rather than books, it archives actual plant specimens. Each plant is flattened, dried, and attached to an individual sheet. Herbarium specimens provide an invaluable physical record of each plant, far more complete and scientifically useful than any written description or drawing could be.
Creating and Maintaining Herbarium Specimens
- If possible, an entire plant, including roots, is collected in the field. Current botanical collecting expeditions also take digital photographs, GPS coordinates, and collect additional material for DNA analysis.
- Specimens are arranged to show all parts to maximum advantage, then flattened using a plant press typically made up of cardboard and wooden frames that are tightened around the specimens using straps.
- The specimen is dried in the air or in an oven.
- The specimen is sterilized by freezing at -18° C for at least one week.
- Using special archival materials, the dry specimen is mounted to heavy paper.
- The specimen is identified using floras, comparison to other specimens, and/or the opinions of experts, if not previously done in the field.
- The species name, collection location and date, habitat description, map or global positioning system coordinates, collector's name, and any other pertinent information are typed on a label, which is attached to the sheet.
- Specimens are organized by evolutionary relationships, family, then genus and stored in metal cabinets, with care taken to prevent insect or other damage. Properly archived specimens can last indefinitely.
- Specimens are re-frozen (e.g. once a year) on a rotation to ensure preservation.
- Green plants are not allowed into the herbarium room. They are sealed in a Ziploc bag; other herbaria may use microwaves.
Visit the Herbarium
Contact Associate Director of Research: aher [at] stanford.edu (Adriana Hernandez)