About Us


California Tortoiseshell Butterflies

Thursday, March 22 & 29, 9am - 9:30 am
On sunny mornings in late March California Tortoiseshell butterflies gather at an odd and secret place in the Garden before they fly off to lay their eggs in bountiful blue blooms. Gather at the Admission Kiosk and we'll venture to the Redwood Grove side of Centennial to look for these butterflies and learn more about their wandering ways. Weather postpones tour.
Free with Garden Admission. No registration required

Horticultural Walk: California with Horticulturist Ken Bates
Wednesday, April 4, 1pm - 2:30 pm
Join Horticulturists Ken Bates and Ben Anderson for a tour through the California Area, the Garden’s largest collection. See native flora from diverse regions of the state. Representing close to one-quarter of the state’s native species, the U.C. Botanical Garden showcases one of the largest species collections of native California plants anywhere. Free; members only; registration required
Members only, free
Reservations required. Call 510-643-2755

Touring of the state of California will reveal to you its great diversity of wonderful specimen plants and vegetation. Think giant sequoia (Sequoiadendron giganteum) and redwood forest (Sequoia sempervirens). A tour of Vernal Poolthe Garden’s California Area will present you with a wide range of these plants, both in vegetation groupings and as individuals. Plants from throughout the state are grouped here by over 25 vegetation assemblages, which are also called plant communities. Garden visitors are perhaps familiar with the area’s alpine fell-field, vernal pool and chaparral beds. Other plant communities have a looser association, such as ‘Berkeley Hills’ near the Oak Knoll.

The Garden was founded in 1890 on central campus to serve the teaching needs of the Department of Botany. Willis Linn Jepson was an early participant in the Garden’s development and by 1892 over 600 kinds of California native trees and shrubs had been planted. Once the Garden was relocated to its current site in the 1920s, the California Area was reestablished according to the geographic layout developed by Professor J.W. Gregg of the Department of Landscape Architecture. An additional eight major geographic collections were also established.

The California Area occupies the largest collection acreage of the Garden at 14.5 acres, including the Mather Redwood Grove. It is one of the most diverse collections of California native plants in the world, including over 2,900 accessions of 1,071 species (1,600 taxa) and 301 Ceanothus oliganthusrare taxa, several on the brink of extinction. Large genera that are well-represented include California-lilac (Ceanothus), manzanita (Arctostaphylos) and geophytes - plants from bulbs or corms.

A great deal of the early development in the California Area was accomplished by Harry Roberts in the 1950s and then by Garden horticulturist Wayne Roderick in the sixties and early seventies. Mr. Roderick created early versions of the alpine fell-field, vernal pool, bulb beds and serpentine plant displays before he left in 1976. He was an internationally known expert on the California flora, especially of geophytes, and established connections with plant lovers in many other parts of the world. Roderick was a tough act to follow.

Roger Raiche was assigned to the California Area in 1981, a plumb job for a man fascinated with all plants. Raiche spent nearly every weekend traveling the roads and trails in California, exploring the native flora and scenery. He developed a deep interest in serpentine-endemic species and plant communities and brought back countless seeds and cuttings to add to the collection. Literally half of the accessions in the California Area today were collected by Raiche or by Raiche with others.

It was during Raiche’s tenure that support was found to expand and completely rebuild the alpine fell-field and serpentine plant community displays. Both were designed by landscape architect Ron Lutsko, with rock work completed by master stone mason Philip Johnson. Both projects were funded by numerous Garden donors, inspired by Raiche’s enthusiasm and expertise. The alpine fell-field looks “as if the oak tree canopy had been trimmed back to reveal a natural alpine site,” said one donor.

Horticulturist Nathan Smith joined the Garden staff to work with Raiche in 2001. As Raiche reduced his work hours during transition to retirement and a new career in landscape design and installation, Smith learned the intricacies of this collection. In time and with lots of hard work, Smith reclaimed what had been an area of tenacious weeds to develop and expand the Channel Islands plant display. Colleagues at the Santa Barbara Botanic Garden and others assisted with acquisition of plant material.

A major challenge in maintaining this diverse collection is staffing. Until last year, the Garden has had 1.5 staff to work in this collection. At present we have one full-time horticulturist, Ken Bates, working diligently and with the help of volunteers. Our ability to support and build the collection are held back by this staffing reduction. Contributions to the California Area Endowment fund would help us return the staffing level back to 1.5 FTE.

The organization by plant community provides critical support of the teaching needs of campus courses. Over 1,000 UCB general biology students visit the Garden twice eachyear for specific lessons on plant communities and ecology. Many other courses from UCB and local community and state colleges utilize this collection for a variety of lessons in plant identification, ecology, and effects of global climate change.

Interpretive signage is being added, with signs about the pygmy forest, Channel Islands plants, chaparral, alpine fell-field, plant communities and conservation. These will be in place by late summer. Docent Publications Committee members researched these topics and provided draft language which was edited by staff. Drafts were honed during a prototype phase by the Garden community (staff, volunteers, visitors). Funding was provided by the Stanley Smith Horticultural Trust and the Elvenia J. Slosson Endowment for Horticultural Research.

Research in the Collection
Overall, the Garden is used for a wide variety of research and teaching purposes. In the California Area, UCB Professor David Ackerly sampled extensively from the collection for his work on the evolution of chaparral. This effort was published as “Adaptation, Niche Conservatism, and Convergence: Comparative Studies of Leaf Evolution in the California Chaparral” American Midland Naturalist 2004, 163(4):654-671, and summarized in the Winter/Spring 2005 Garden Newsletter. Dr. Ackerly continues to use this collection for research, currently on the impacts of global climate change. This semester his freshman seminar class is working with Garden temperature and phenology (flowering events) data to see how the flowering of plants in the Garden has changed over the last several decades. Students are following the flowering of 300 species. It was, and is, due to the efforts of volunteers to record flowering data (since the late 1980s) that makes this work possible today.
Vernal Pool
UCB Assistant Professor Chelsea Specht and her graduate students have sampled extensively in the Garden, specifically the onion genus Allium in the California Area. The work on Allium was published in 2008 as “A molecular phylogeny of the wild onions (Allium; Alliaceae): with a focus on the western North American center of diversity,” by Nhu Nguyen, Heather E. Driscoll, and Chelsea Specht, in Molecular Phylogenetics and Evolution.

UCB Professor Alex Purcell is studying Pierce’s disease, a serious problem in California’s vineyards and almond orchards. This bacterial disease is transmitted by various insects, including the introduced glassy-winged sharpshooter. Members of Dr. Purcell’s lab regularly tap the California grapevine for sap necessary for experiments. See Dr. Purcell’s web site for more details.

Plants from the California Area, as is the case from the whole of the Garden, have supported, at least in part, dozens of graduate degrees and continuing research of academics around the world. In addition to these very formal studies, many undergraduate students use the California Area for class projects, such as studying western fence lizard behavior or pipevine swallowtail butterfly populations. Sometimes cuttings are taken to support hungry insect colonies in the UCB Department of Environmental Science, Policy, and Management.

Conservation in the Collection
Plant conservation is supported in numerous ways in the California Area. The collection includes holdings of 301 rare taxa (as recognized by the California Native Plant Society, federal and state governments). These holdings provide the basis for several introduction efforts in the Bay Area.

The Garden became a participating institution in the national Center for Plant Conservation in 1987, taking its first actions under that program in 1988. The Center is a consortium of gardens and arboreta across the US dedicated to preventing plant extinctions. Now including 36 participating institutions, the Center provides technical guidance and helps develop protocols for all aspects of conservation actions. These are guided by a scientific advisory council and the findings of its sponsored symposia.

Basic activities are collecting seeds for long term storage, learning how to grow species to reproductive maturity, and if needed, experimenting with augmentations and/or introductions to increase the number of populations. It takes a village—partnerships in conservation ‘on the ground’ benefit from participation from a wide variety of interested parties. Garden staff benefit from the financial support and participation of the US Fish & Wildlife Service, California Department of State Parks, Bureau of Land Management, Center for Plant Conservation and members of the California Native Plant Society.
Ceanothus oliganthus
Garden staff launched introduction efforts for the annual herb Mount Diablo buckwheat (Eriogonum truncatum) in late 2007, with additional introductions in 2009. Mount Diablo buckwheat working group members continue to monitor these sites, as well as the natural site. The monitoring data will inform the working group’s future efforts.

In 2009, Curator Holly Forbes, Assistant Curator Barbara Keller and Propagator John Domzalski made their first introduction efforts for the Baker’s larkspur (Delphinium bakeri), a herbaceous perennial. Stubbs Vineyard was the site of a trial planting in March 2009, at which eleven nearly flowering plants were placed in an existing fenced area. Ten of them flowered and several set and dropped seeds that spring. One year later we are encouraged by the survival of six plants and the observation of nearly 40 seedlings. Tom Stubbs is an enthusiastic supporter of this project and his Pekingese, Pepper, is a self-appointed guide and mascot. Learn more about Stubbs Vineyard here: http://www.stubbsvineyard.com/

In 2008, we received the gracious permission of Sally and Mike Gale to develop a Baker’s larkspur population on their Chileno Valley Ranch. Given the drought situation at the time, Sally suggested waiting for a better rainfall year. In December 2009, we placed 45 dormant plants in a site of oaks and bays near an intermittent stream. In March 2010, nearly all the plants are in flower bud, and we are hopeful for good seed set and regeneration via seeds in the coming years. Thirty of these plants were provided by the Regional Parks Botanic Garden in 2008. Learn more about Chileno Valley Ranch at: http://www.chilenobnb.com/index.html

In January 2010, we planted 40 mature plants from 20 maternal lines, just coming out of summer/winter dormancy, at a site near Soulajule Reservoir in west Marin County. This is almost due south of the only known wild site. The board of the Marin Municipal Water District (MMWD) enthusiastically gave permission to establish this federally and state-listed endangered species on lands they steward. MMWD vegetation ecologist Andrea Williams, US Fish & Wildlife Service members Kate Symonds, Valary Bloom, and Josh Hull, and CNPS volunteer M.L. Carle helped with the planting. In March 2010, all the plants have flower buds and should provide a great blue show in April. This site is fenced to protect the plants from cattle and deer browsing, it has the most diversity of flowering species of three introduction sites. This planting effort was covered by the media in KWMR radio on January 29th with coverage by Jacoba Charles. Vernal Poolhttp://westmarinradio.net/news/list/ and in the West Marin Citizen on January 14th.

Kenwood Marsh checkerbloom (Sidalcea oregana ssp. valida) is a perennial herb known from only two sites in Sonoma County. Owners of the Deerfield Ranch Winery have been very supportive of improving the situation for this species on their property. With seeds collected by USFWS member Kate Symonds and California Department of Fish & Game botanist Gene Cooley, Garden Propagator John Domzalski grew out several plants in our nursery. These were used to create a planting in April 2009 adjacent to the naturally occurring sites at the winery. The winery owners created the Kenwood Marsh Checkerbloom Society to assist with fundraising for conservation efforts on its behalf. See: http://deerfieldranch.com/CheckerBloomSoc.html

San Mateo thornmint (Acanthomintha duttonii) is an annual flower whose numbers have been declining drastically at its only known locality in San Mateo County. The Creekside Center for Earth Observation launched a conservation project for this species in 2008, within which they contracted with the Garden to generate enough seeds to augment the existing population and in the future will attempt to create more populations. Garden Propagator John Domzalski developed a protocol to get good germination and Curator Holly Forbes documented their progress. Our success has been such that the Garden was able to provide 12,500 seeds for an experimental planting at the wild locality in November 2009. Christal Niederer and volunteers are monitoring the germination and progress of these plants, which looks very promising. In the meantime, John and Holly have sown another 180 pots of seeds provided by Dr. Bruce Pavlik of Mills College, in hopes of even greater seed numbers.

Supporting the Garden through Plant Sales
The volunteer propagation program offers a comprehensive selection of native Californian plants. While we have a large offering of the quintessential California natives, California-lilac (Ceanothus) and manzanita (Arctostaphylos), we also grow some of the lesser known, but Ceanothus oliganthushighly desirable plants suitable for a drought-resistant, mediterranean-climate garden. We have beautiful asters such as Corethrogyne and Erigeron, the California larkspur (Delphinium californicum), a variety of succulent Dudleya and a nice choice of trees and shrubs such as the pink flowering currant (Ribes sanquineum), the snowdrop bush (Styrax officinalis), and some flannelbush cultivars (Fremontodendron). These are but a few of the diverse collection we offer for sale. Visit our native plant propagation blog at http://ucbgcn.blogspot.com/; it has a list of plants currently available and their pricing.

Plants are available on the Plant Sales Deck every day the Garden is open from 10:30 am until 4:30 pm.

—Holly Forbes & Bryan Gim