Summary

The Oakmead Herbarium, located in the Leslie Shao-ming Sun Field Station at Jasper Ridge, contains more than 6000 mounted specimens representing almost 900 vascular plant taxa found at the Jasper Ridge Biological Preserve, together with collections of bryophytes and lichens.  The 850,000-specimen Dudley Herbarium, established in 1892 at Stanford, was moved to the California Academy of Sciences in 1975. Professor John Hunter Thomas retained a collection of his Jasper Ridge specimens, which became the cornerstone of the JROH. The earliest specimen in the JROH collection was made by Volney Rattan in 1867. 

Since 1996, volunteer docents and affiliates have been responsible for systematically reviewing, updating, and maintaining the collections. Vouchers and digital imagery continue to be added on a regular basis.  At present we have almost 19,000 images in a Jasper Ridge gallery on Flickr.

Ongoing research and support activities at JROH include field observation, data recording, specimen collection, voucher preparation, conservation, database management, and collection and curation of digital imagery.  Through these activities, new invasive species such as Dittrichia graveolens, Brachypodium sylvaticum, and Parentucellia viscosa were detected early enough that their populations could be controlled, and native taxa continue to be added to the JRBP flora. Primary source materials at the herbarium may be used to establish habitat associations of plant species, and to discern and monitor trends in plant populations, biodiversity, and habitat resilience in response to disturbance and climate change.

In addition to maintaining the collections and associated databases, herbarium docents provide assistance with identification and field sampling for Jasper Ridge research projects, including investigations by undergraduates, graduate, and post-doctoral students; contribute to ongoing research projects conducted by researchers from Stanford and other institutions; and teach classes on a variety of subjects for the Jasper Ridge community.

JROH is a member of the Consortium of California Herbaria, an online portal to specimens housed in participating institutions.   The Jasper Ridge vascular plant list, with links to curated photographs taken at Jasper Ridge, is updated regularly and is available on the Oakmead Herbarium home page.