From biodiversity hotspots around the world to a collection of approximately 2 million specimens, our department seeks to discover, document, and protect Earth's incredible diversity of land plants. 

From the slopes of Brazil, moss-filled Philippine forests, the spiny desert of Madagascar, to California's own mountain ranges—Academy botanists travel the world to discover new species, collect plants for our herbarium, and contribute to our extensive botany database, which currently contains records for approximately 715,000 specimens.

With a history of pioneering action that began in 1893 with botany curator Alice Eastwood, today's department is a robust collection of leading researchers, scientists, fellows, and students. Our resources include a 2.3 million-specimen collection containing more than 21,000 types, as well as the John T. Howell Botanical Laboratory.

A magnolia herbarium specimen


The California Academy of Sciences' herbarium is the largest collection of vascular plants in the western U.S. and the sixth-largest collection in the country. The CAS collection includes ~2.3 million plant specimens with almost 21,000 types. Over 95% of the specimens are vascular seed plants; the remainder are ferns and a growing collection of bryophytes at ~200,000 specimens.

Louteridium donnell pollen


Learn more about our department's areas of focus—active, ongoing research that seeks to answer some of the biggest questions in the field.

Bryophytes of Kauai


See where our research takes us, what partners we're working with, what impacts we've had on local communities, and what discoveries we've made thus far.

Trinity Alps


Our researchers discover new species, explore evolutionary relationships, and address important questions about biogeography and biodiversity.

Contact Us

Collections inquiries:
Emily Magnaghi
Collection Manager
California Academy of Sciences
55 Music Concourse Dr.
San Francisco, CA 94118
(415) 379-5392

Department History

Learn more about our department's century and a half of scientific history.

Frequently Asked Questions

Visiting our collections, identifying backyard plants, and more.