Balboa Park’s Urban Forest

Sustain, manage, and grow Balboa Park’s natural wonders

Home to the San Diego Zoo and dozens of cultural institutions, Balboa Park is also one of California’s most significant and iconic landscapes. More than a century ago, a scrub-filled mesa near downtown San Diego was transformed into an exotic green oasis through the planting of hundreds of trees. In 1892, Kate Sessions, the “Mother of Balboa Park,” began planting 100 trees in the park each year in exchange for leasing parkland for her nursery. Such citizen forestry initiatives continue to this day with the annual Arbor Day tree-planting celebration and the Conservancy’s many projects in partnership with various local nonprofits and the City of San Diego Department of Park and Recreation.

Tree Balboa Park

500+ New Trees to Restore Balboa Park’s Urban Forest

Tree Balboa Park is a massive reforestation project to plant 500+ trees within Balboa Park over two years, helping restore the park’s depleted tree canopy. The project launched in summer 2017 after the Conservancy secured a $378,297 state grant from CAL FIRE, the California Department of Forestry and Fire Protection, which selected Tree Balboa Park as part of its urban forest expansion and improvement initiative through the state’s Greenhouse Gas Reduction Fund (GGRF). Tree Balboa Park’s primary partner, the City of San Diego’s Park and Recreation Department, is making significant in-kind contributions valued at $337,702 for a project total of $715,999.



Tree Balboa Park helps reestablish Balboa Park’s historic tree canopy, which lost more than 1,500 trees due to recent drought conditions. Drought-tolerant trees are being planted throughout the park’s 1,200-acre campus to maximize greenhouse gas reduction and provide improved air quality and reduced stormwater runoff. Energy-efficient, water-saving irrigation is also being installed to support the new trees as part of Park and Recreation’s in-kind contribution. The state-of-the-art systems replace older, outmoded systems in the park, thus meeting deferred maintenance needs.

With the City of San Diego’s tree canopy estimated at 20 percent of what it should be to sustain the health and well-being of its residents, Tree Balboa Park will help expand and diversify the city’s overall tree canopy and fulfill state-mandated urban reforestation and greenhouse gas emission reduction goals. The project also makes a significant contribution to the city’s Climate Action Plan, a core component of which is its Urban Tree Canopy Plan to boost the tree canopy to 35 percent by 2035.

Another project partner, Urban Corps of San Diego is providing part-time youth workers from disadvantaged communities to help with the tree planting. The youth workers from Urban Corps are certified by the California Conservation Corps and receive additional training from the Tree Balboa Park project arborist and are educated about urban reforestation.


A Data-Driven Collaborative Process

Tree Balboa Park represents an unprecedented collaboration among state, municipal, and nonprofit agencies from various sectors to address an urgent environmental need within the park, and the city as a whole. The combined resources and expertise of all partners ensures the latest best practices, technologies, and techniques in horticulture, reforestation, environmental sustainability, landscape design, and volunteer training are brought to bear to optimize the significant state funding that’s been granted to restore and enhance Balboa Park’s iconic landscape.

The list of 500+ trees to be planted is being developed through a rigorous process involving multiple experts: trained horticultural staff with Park and Recreation who are highly familiar with the park; the Tree San Diego Executive Director/President and board members, including a certified arborist; and the Conservancy’s CEO with the Director of Planning, Design, and Programs (who serves as the project manager), both credentialed landscape architect professionals and planners.

The data-driven tree planting plan is based on results of a comprehensive tree inventory of the park—the first of its kind to be undertaken in decades, funded in part by the San Diego Foundation and the Johanna A. Favrot Fund. All tree species and locations are being selected with Park and Recreation’s cooperation to ensure the highest level of environmental benefits (greenhouse gas reduction, stormwater runoff protection, drought tolerance, shade benefits, etc.) while improving the overall health and beauty of the park’s landscape.

Ongoing community participation in Tree Balboa Park is facilitated through regular interface with and input from city departments and officials, including the Balboa Park Committee, representing city residents and park users; the Tree Balboa Park advisory committee of park stakeholders; and the Conservancy Board of Trustees, including liaisons from the San Diego Mayor’s Office, the Director of Park and Recreation, the City Council, the County Board of Supervisors, and the State Assembly.

One of Tree Balboa Park’s goals is to develop a model urban reforestation program based on public-private partnerships and collaborative resource allocation, advancing Balboa Park as a nationally recognized innovator in urban environmental sustainability.


Tree Planting Progress Update

As of December 2019, over 580 trees have been planted  since the start of the initiative, including along Morley Field Drive, in the Cypress Grove Picnic Area, and throughout the West Mesa. The final 45 trees needed to achieve the aims of the initiative will be planted early 2020.

List of Tree Species Planted

The following list of tree species were selected for their high carbon sequestration qualities, climate appropriate character, productivity in our Mediterranean climate, and aesthetic qualities for Balboa Park’s botanical collection.

African fern pine, Afrocarpus gracilior
African tulip tree, Spathodea campanulata
After Dark peppermint willow, Agonis flexuosa
‘After Dark’
White jacaranda, Jacaranda mimosifolia ‘Alba’
Arborvitae, Thuja orientalis
Atlas cedar, Cedrus atlantica ‘Glauca’
Australian tea tree, Leptospermum laevigatum
Bald cypress, Taxodium distichum
Brisbane Box, Lophostemon confertus
Burgundy peppermint willow, Agonis flexuosa ‘Burgundy’
California sycamore, Platanus racemosa
Camphor, Cinnamomum camphora
Canary island pine, Pinus canariensis
Canyon live oak, Quercus chrysolepis
Catalina cherry, Prunus ilicifolia ssp. lyonii
Chinese juniper, Juniperus chinensis ‘Foemina’
Chinese pistache, Pistacia chinensis
Coast live oak, Quercus agrifolia
Cork oak, Quercus oak
Deodor cedar, Cedrus deodora
Engelmann oak, Quercus engelmannii
Evergreen ash, Fraxinus uhdei
Evergreen pear, Pyrus kawakamii
Fastigiata goldenrain, Koelreuteria paniculata
Firewheel tree, Stenocarpus sinuatus
Floss-silk tree, Ceiba speciosa
Flowering ornamental pear, Pyrus calleryana
Foemina Chinese Juniper, Juniperus chinensis ‘Foemina’
Gold markhamia, Markhamia lutea
Gold medallion, Cassia leptophylla
Golden champaca, Magnolia champaca
Golden rain, Koelreuteria paniculata
Golden trumpet, Tabebuia chrysotricha
Guadalupe cypress, Cupressus guadalupensis
Hollyleaf cherry, Prunus ilicifolia
Hong Kong orchid, Bauhinia x blakeana
Incense cedar, Calocedrus decurrens
Indian Laurel Fig, Ficus microcarpa
Italian cypress ‘tiny towers,’ Cupressus sempervirens ‘Monshel’
Jacaranda, Jacaranda mimosifolia
Kashmir cypress, Cupressus cashmeriana
Kauri pine, Agathis australe
Leyland cypress, Cupressocyparis leylandii
Little Gem magnolia, Michelia doltsopa ‘Silver Cloud’
Long-leaf yellow wood, Podocarpus henkelii
Marina madrone, Arbutus ‘Marina’
Mondell pine, Pinus eldarica
Monterey cypress, Cupressus macrocarpa
Montezuma bald cypress, Taxodium mucronatum
Moreton Bay Chestnut
Moreton Bay fig
Morning cloud chitalpa
Naked coral tree
Naylor’s blue leyland cypress
New Zealand Christmas
Norfolk Island pine, Araucaria heterophylla
One-seed juniper, Juniperus monosperma
Peruvian Pepper tree
Pink cedar
Pink melaleuca
Pink trumpet tree, Tabebuia impetiginosa
Primrose tree (aka Cow itch tree)
Purple leaf-acacia
Queensland kouri
Randy magnolia
Red flowering gum, Corymbia ficifolia
Red ironbark
Rocky mountain juniper
Rose Marie magnolia
Rustyleaf fig
Shoestring acacia
Silver cloud michelia
Small leaved fig
Southern magnolia, Magnolia grandifolia
Strawberry snowball
Sweetshade, Hymenosporum flavum
Tecate cypress, Hesperocyparis forbesii
Thundercloud purple-leaf plum
Tolleson’s blue weeping juniper, Juniperus scopulorum
Torrey pine, Pinus torreyana
Tulip tree
Valley oak
Western redbud
Wollemia nobilis
Yellow Bells
Yellow poinciana (aka horsebush)


Environmental Impact

Using the Center for Urban Forest Research’s Tree Carbon Calculator and based on the projected tree mix and planting locations for all trees at the time of the grant proposal submission, the estimated greenhouse gas benefit of this project is 1,745 metric tons of carbon stored in live project trees along with a 14-metric-ton CO2e greenhouse gas benefit from energy savings (based on a maintenance period of two years). With 88 metric tons of CO2e greenhouse gas emissions resulting from project implementation, the net greenhouse gas benefit from the proposed project is 1,672 metric tons of CO2e. It is also estimated that approximately 16.6 million gallons of stormwater runoff will be avoided as a result of this project. Note: actual environmental benefit numbers will vary depending on the final mix of trees planted and their locations.


Educational Outreach and Visitor Engagement

Tree Balboa Park includes outreach initiatives to educate schoolchildren, park visitors, and the public about the importance of healthy urban forests and the role of trees in environmental sustainability. Many of these outreach programs were funded with the CAL FIRE grant.


 Young Tree Stewards in Balboa Park

Tree Stewards

Partnering with local nonprofit Tree San Diego, the Conservancy developed a Tree Stewards program to help manage, maintain, and expand Balboa Park’s urban forest. Tree Stewards are specially trained to monitor newly planted trees, general health conditions of existing trees, soil moisture surrounding new trees, including identifying irrigation needs, and possible pest infestation. In 2019, the program contained a total of 45 Tree Stewards who contributed over 700 hours of service.

Young Tree Stewards

The Tree Balboa Park project includes a Young Tree Stewards volunteer program, developed by local nonprofit Tree San Diego. The program kicked off on November 6, 2017, when 150 fifth graders from Porter Elementary descended on Balboa Park to receive a full school day of training from arborists and volunteer teachers with Tree San Diego. Building on their classroom lessons, the students took turns constructing berms, laying down mulch, and practicing different methods for watering trees, much to the benefit of trees recently planted along Morley Field Drive. This unique program was partially funded by the Outdoor Foundation and the San Diego Foundation.


Tree Plotter: A Tree Inventory Tracking Software

The public is invited to view Tree Balboa Park’s progress and learn interesting facts about all the park’s trees by Tree Plotter on their computer, phone, or tablet via the following link. Visitors can search for trees by both common and botanical name, while also filtering their results by date planted, diameter, genus, maintenance zone, project, and status.


Visitor Information and Tours

A permanent interpretive panel and additional temporary signage at primary visitor locations and at new tree-planting sites will introduce millions of visitors to Tree Balboa Park and the importance of urban reforestation. Closer to the project’s completion, a Tree Balboa Park brochure and self-guided walking tour will be available in the Conservancy-operated park Visitors Center.

Funding for this project has been provided by the California Greenhouse Gas Reduction Fund through the California Department of Forestry and Fire Protection (CAL FIRE), Urban and Community Forestry Program.



Did you know that nearly 20% of Balboa Park’s 15,302 trees are designated Poor, Critical or Dead due to disease & drought?

The Conservancy is preserving, protecting, and renewing Balboa Park’s urban forest with the help of tree lovers like YOU.


We Collect Data. We completed a comprehensive Tree Inventory for all of Balboa Park, locating each tree, its species and condition using GIS. This helps us better care for the trees and supports strategic decision-making.

We Plant Trees. Through our program Tree Balboa Park we’re planting 500 trees in partnership with the City of San Diego through a generous grant from CAL FIRE.

We Educate. We work with Urban Corps to plant trees in Balboa Park, providing young adults with paid job training, and important work and life skills. With Tree San Diego, we train disadvantaged students to plant and water trees—providing knowledge and hands-on experience they can use in their own backyard.

We Advocate. We partner with the City of San Diego Parks and Recreation Department and organizations like CAL FIRE, the San Diego Regional Urban Forests Council, Urban Corps, and Tree San Diego to increase the awareness and support for our urban forest.

Are You a Tree lover?

The​ ​Conservancy​ ​serves as​ ​a​ ​catalyst​ ​for​ ​excellence in the​ ​park—but we cannot do it alone.​ We need to build our community of supporters to promote the growth of the volunteer programs, to help reforest Balboa Park, to advocate for sustainable revenue streams, and to plan and execute meaningful park projects.

With your help, we’re investing in the reforestation of Balboa Park. Trees are an important part of helping the city reach its goals in the recently approved Climate Action Plan, and we are doing our part to help preserve, protect and renew this incredible natural resource.

How you can help

Give a Gift 

Help build the legacy of Balboa Park when you donate to the Trees Forever fund. The Balboa Park Conservancy provides expertise, resources and advocacy to implement all of these important urban forestry initiatives. Planting a tree is one of the single most meaningful ways to recognize someone important you.  Any size gift can become a “Tribute Gift” – made in honor or memory of someone special. Please let us know if you would like to recognize someone with the gift of reforestation for Balboa Park. Please email or call us at (619) 331-1991 to create your experience.

Become a Tree Steward

Help strengthen the sustainability of Balboa park when you become a trained volunteer Tree Steward—supporting the planting, maintenance and care of this unique urban forest.

Advocate for Trees

Follow and support the Balboa Park Conservancy and other local organizations like San Diego Regional Urban Forests Council, Tree San Diego, Urban Corps who all work towards more sustainable, vital communities.