The Oasis Reborn: Understanding Aldrich Park’s Reforestation Initiative
Aldrich Park is the heart of the University of California, Irvine campus, and it is in the middle of a long-term reforestation effort. As UC Irvine reported in May 2025, 95 new trees have been planted near the eastern side of the park and at the Crawford Athletics Complex, the latest step in replacing aging eucalyptus with native California species and other long-lived shade trees.
The park dates back to the campus’s founding design. Founding Chancellor Daniel G. Aldrich Jr. and architect William Pereira planned a campus unlike traditional universities, with a circular park crisscrossed by pathways at its center, designed as an urban forest that would connect students and faculty with nature. Concentric rings of buildings would extend outward from the park, symbolizing knowledge spreading outward, and greenbelts would link the park to every campus neighborhood. Originally called Campus Park, the 19-acre space hosted commencement ceremonies and many campus celebrations. It was renamed Aldrich Park in 1984, the year Aldrich retired. According to UC Irvine, Aldrich’s background in agriculture shaped his intention to make the campus environmentally friendly.
While the park and surrounding buildings were being developed, the campus needed shade quickly, so it planted several species of fast-growing eucalyptus, trees native to Australia. Eucalyptus became the dominant species planted during the first two decades of campus development. That solved the immediate problem but left the urban forest heavily dependent on a single group of trees.
In 1996, under Chancellor Laurel Wilkening, UC Irvine created the Sustainable Landscape Program, known as the Green and Gold Plan. It set objectives for the campus’s urban forest, including greater species and age diversity to improve its long-term health, and it encourages the gradual replacement of eucalyptus with native California trees and other shade trees of ecological value. Today the campus has about 30,000 trees of 317 types, and its goal is that no single species accounts for more than 10% of the total.
The campus regularly assesses its eucalyptus and other trees to identify those in declining health or posing a hazard. In 2021, close to 300 eucalyptus trees in Aldrich Park, at the Crawford Athletics Complex and along Academy Way were removed; trees planted in the 1960s are now near the end of their natural lifespan. Species for the new plantings were chosen in consultation with a campus biologist and a landscape architect. They include the California natives Western Sycamore, Western Redbud, Engelmann Oak and Coast Live Oak, along with Green and Gold Plan approved species such as Southern Live Oak, Chinese Elm, ‘Majestic Beauty’ Ash, Bald Cypress and Chinese Tallow. UC Irvine has been recognized by the Arbor Day Foundation as a Tree Campus for the past 15 years, reflecting stewardship of the campus forest by students, staff and faculty.
Beyond Aesthetics: The Ecological Imperative of Native Trees in Urban Settings
The move from eucalyptus to native species is about more than appearance. Native trees evolved alongside local birds, insects and other wildlife, and they provide the food, nectar, pollen and shelter those species depend on. Many introduced trees common in Southern California, such as jacarandas, ficus and palms, add beauty and shade but support fewer local species. As a discussion of non-native trees in Los Angeles has pointed out, non-native trees can still be useful in dense urban areas where few natives will grow, but natives generally support richer local ecosystems.
Diversity also makes an urban forest more resilient. A forest dominated by one species can be devastated by a single pest or disease, while a mix of species spreads that risk. A widely used guideline, the 10-20-30 rule, recommends that no more than 10% of trees in an urban forest come from one species, 20% from one genus and 30% from one family. UC Irvine’s 10% single-species goal follows the same logic. Better tree inventories and data-driven management, a trend described in the article “Seeing the Trees for the Forest,” make it easier for cities and campuses to track species composition and tree health and to plan replacements as older trees decline.
Seen this way, the removal of nearly 300 eucalyptus trees in 2021 was part of a planned transition. Replacing trees that are near the end of their lifespan with long-lived natives and other suitable shade trees increases the diversity and long-term health of the campus forest and provides more habitat for pollinators and other regional species.
A Living Laboratory: Aldrich Park as a Model for Sustainable University Landscapes
Aldrich Park is part of a broader plan for campus open space. UC Irvine’s Naturescape Vision, completed in 2018, builds on the campus’s earlier sustainability planning for all of its open space, which accounts for about one-third of the campus footprint. It aims to use these areas for interdisciplinary teaching and research, campus life and community engagement, art and culture, recreation and wellness, and habitat and watershed management. That makes the park a place where students and faculty can observe ecological restoration and sustainable land management firsthand.
Planting is only the beginning. The article “As Sustainable Landscapes Become the Norm, Maintenance Isn’t Keeping Up” notes that traditional maintenance practices such as routine mowing and spraying are poorly suited to ecological landscapes and native plantings, which need crews with different training and expertise. Long-term success at Aldrich Park, as elsewhere, depends on maintaining the new plantings as carefully as they were chosen.
The park’s history is also part of the campus’s story. “The Anteater Experience,” a UC Irvine Libraries exhibit marking the university’s 60th anniversary, includes Aldrich Park among the places that shaped campus life.
Cultivating Community and Well-being: The Social Impact of Urban Green Spaces
Urban green spaces also matter for people. The U.S. Environmental Protection Agency notes that green infrastructure, including tree canopy and parks, offers social benefits such as places for physical activity and recreation. Reviews of research on urban greenspace, including an annotated literature review from Harvard, report positive associations between time in green spaces and attention, mood and reduced symptoms of stress, depression and anxiety. On a busy campus, a park offers a place to rest, walk or study outdoors.
Parks also strengthen social ties by serving as shared gathering places. Research on urban park environments and public health links parks to more social interaction and a stronger sense of community. Access, however, is not equal. Lower-income neighborhoods often have fewer trees and less park space, and so receive fewer of these benefits, which is why “tree equity” has become an important goal in urban planning.
Aldrich Park serves both purposes. “Aldrich Park serves the campus community in myriad ways – from hosting large campus events and recreation to providing an opportunity for respite and connection to nature,” says Matt Deines, principal physical planner for Campus Planning & Sustainability. “Our tree canopy is an important feature of Aldrich Park and the campus as a whole, providing shade, improving air quality and creating habitat for local bird species,” he adds. “As a campus, it’s important for us to continue to protect the original vision of Aldrich Park and continue to invest in it, as we have through this reforestation effort.”
Reference:
- Greenery gets glow-up: Aldrich Park sees rejuvenation through reforestation (UC Irvine News)
- The Anteater Experience: Aldrich Park (UC Irvine Libraries)
- Annotated Literature Review: Health Benefits of Urban Greenspace
- Analysis of Urban Park Environment Effects on National Health
- As Sustainable Landscapes Become the Norm, Maintenance Isn’t Keeping Up
- Seeing the Trees for the Forest
- Social Benefits of Green Infrastructure (U.S. EPA)
- The Complex Question of Planting Non-Native Trees in Los Angeles