Cycads are the most primitive of surviving gymnosperms, or cone-bearing plants with palm-like leaves and a thick soft stem of storage tissue, mostly lacking any true wood. Their fossil record dates back to the early Mesozoic – about three hundred million years BP. Their resemblance to palms or tree ferns ends when the plants produce cones. These cones resemble somewhat the cones of their relatives, the conifers, but they are generally larger. Cycads are dioecious, meaning that each plant has either female or male reproductive structures. Tropical and subtropical in distribution, cycads are found naturally in warmer regions of North and South America, Africa, Asia, and Australia.
The Garden grows cycads in the Tropical House and other greenhouses, along with a range of hardier species grown out of doors in collections throughout the Garden. Surrounding the Conference Center, the Cycad and Palm Garden represents one of the Garden’s few taxonomical outdoor collections. A new cycad display is being created adjacent to Julia Morgan Hall.
Along with the rest of the Garden’s collection, cycads serve as a teaching and research resource at UC Berkeley and other universities around the world.
Looking for a specific cycad? Check our plant database.
Use this UC Botanical Garden map for approximate locations of cycad displays.
The Plant Collections Network and the Global Conservation Consortium for Cycads
The University of California Botanical Garden at Berkeley (UCBG) is part of the Cycad Multisite Collection of the Plant Collections Network (PCN). The PCN is a joint program of the American Public Gardens Association and the USDA’s Agricultural Research Service. The program recognizes excellence in plant germplasm preservation and plant collections managment.
The Garden is also a participant in the Global Conservation Consortium for Cycads, an international effort to coordinate cycad conservation, with an emphasis on preventing extinction in the wild.
The Cycad Collection by the Numbers
Our goal at UCBG is to represent the broadest diversity of taxa possible to support research, teaching, and conservation. Although many of our cycads are missing provenance data (having come from government confiscations) their taxonomic breadth makes them ideal for some avenues of research and for some conservation projects. Nearly 650 cycad accessions of just over 100 species are represented in the collection, including all ten genera. The three best represented genera are Macrozamia from Australia (39% of known taxa), Dioon from Mexico (55% percent of known taxa), and Encephalartos (60% of known taxa). San Francisco Bay Area temperatures are ideal for many Encephalartos, including the taxa that are the focus of our conservation effort, and the monotypic genus Stangeria. Our climate is marginal for the Central and South American taxa from the genus Zamia. The species in the Mexican genera Dioon and Ceratozamia have prospered and coned outside in the Garden. We have a relatively large number of cycads not fully hardy in the Bay Area, such as the beautiful and exotic looking Cycas multipinnata and C. bifida. These, along with the genera Microcycas and Bowenia, require greenhouse care here. Tissue samples continue to be supplied for various research projects and frozen pollen is shared with other collection holders for controlled breeding.
Cycads have been a part of the Garden collection since the late 1930s. The oldest living cycad at UCBG is a sago palm (Cycas revoluta) that was accessioned as a plant in 1950 (an exchange from the Huntington Botanical Gardens). While not the oldest accession at UCBG (that distinction goes to a 1928 accession of Afrocarpus gracilior in the Southern African Area), it is a venerable specimen.
In 2002 the Garden contracted with the US Fish and Wildlife Service (USFWS) to care for about 1,000 cycads, obtained as part of an elaborate sting (called “Operation Botany”) of an illegal importation, chronicled in a New York Times Magazine article that ran on August 28, 2005. Not all of the plants survived the smuggling process, and it took up to four years for some of them to finally leaf out from a dormant state. At the end of the ensuing prosecutions about 700 plants were turned over to the Garden in its capacity as a Plant Rescue Center for the USFWS. Confiscated plants came from several locations in Africa (mainly South Africa) and Asia, as well as from Australia and Mexico. This donation greatly expanded the cycad holdings of the Garden, more than doubling the number of taxa and adding five times the number of accessions previously held.
Our cycad holdings, and particularly the plants derived from the confiscation, represent a major and exciting collection, and a significant responsibility for the Garden. The majority of confiscated plants were in all likelihood removed from the wild by poachers, resulting in a serious drain on already imperiled populations. Cycads are slow to reproduce and often limited in distribution. A number of the southern African taxa we received are very rare in the wild and almost non-existent in botanical garden collections.
Conservation and Research
While the UCBG cycad collection displays broad taxonomic diversity, as part of the Plant Collections Network we designate our holdings as a conservation-based collection with a focus on genetic diversity. With forty species held, the genus Encephalartos is the specific focus of our cycad breeding program. At least two taxa, Encephalartos hirsutus and Encephalartos middelburgensis, obtained from the confiscation are extremely rare in collections and now known to be extinct in the wild. These species, and at least two more in our collection, and four others have been declared extinct in the wild by the International Union for the Conservation of Nature’s Cycad Specialist Group. While the confiscated plants lack provenance, in all likelihood they were collected in the wild. Regardless, the UCBG plants represent some of the last publicly held individuals of these taxa.
Garden staff members are working on collaborative conservation projects involving these and other rare cycad species. Cycads are long-lived and slow to reproduce. Species-specific pollinator insects (often weevils) are absent in our area. We are conducting an artificial breeding program with a goal of producing propagules for future reintroduction into the wild. Pollen from all rare cycad taxa is collected and frozen for future use. Within our collection certain species are quite numerous and have begun to cone regularly. We have successfully pollinated C. bifida, D. tomasellii, E. horridus , E. trispinosus, E. middleburgensis, and E. eugene-maraisii to produce seedlings. Our pollination techniques are undergoing refinement, and we are growing on the first young plants from our breeding efforts.
The UCBG was founded as and continues to be a research collection. Although the cycads are not replete with provenance data, their taxonomic breadth makes them ideal for some avenues of research. Among other projects (see sidebar), former UCB faculty member Dr. Chelsea Specht and her then graduate student Chodon Sass and colleagues explored the possibilities of DNA barcoding within cycads.
Research Publications to Date
Ellstrand, Norman C., Robert Ornduff, and Janet M. Clegg. 1990. “Genetic structure of the Australian cycad, Macrozamia communis (Zamiaceae).” American Journal of Botany 77 (5): 677-681.
Ornduff, Robert. 1996. “Gender performance in a cultivated cohort of the cycad Zamia integrifolia (Zamiaceae).” American Journal of Botany 83 (8): 1006-1015.
Sass, Chodon, Damon P. Little, Dennis Wm. Stevenson, and Chelsea D. Specht. 2007. “DNA barcoding in the Cycadales: Testing the potential of proposed barcoding markers for species identification of cycads.” PLoS ONE. 2 (11): e1154. doi:10.1371/journal.pone.0001154.
Schneider, Edward L., Sherwin Carlquist, and Jeffrey G. Chemnick. 2007. “Scanning electron microscope studies of cycad tracheids.” South African Journal of Botany 73 (4): 512-517.
The Cycad Specialist Group (a member of the International Union for Conservation of Nature Species Survival Commission)
New York Times Magazine, “The Cult of the Cycad”
Berkeley Science Review, “Plant Protectors” Cycads appear in the bottom half of the article.