Joseph Rock planting Hibiscadelphus giffardianus (Hunt Institute); the main campus c. 1940

University of Hawai‘i Campus Arboretum

The grounds of the University of Hawai‘i are an accredited arboretum, showcasing plants from Hawai‘i, the Pacific, and across the tropics, including a number of truly exceptional trees, such as the largest Baobab in the United States. While its primary function is to support the educational mission of the University, the Arboretum is also open to the public. Admission is free, though donations are gratefully accepted through a special UH Foundation fund.

Historical Background

Over a century ago, the University of Hawai‘i was established (as the then College of Hawaii), with the plan to treat the campus as an arboretum. In a 1915 report to the legislature, the Board of Regents extolled the

unexcelled opportunity to establish here in Honolulu a collection of trees and shrubs of tropical and subtropical habit which would have great educational value and soon become an asset of great interest to resident and tourist alike who would be attracted by such a collection of properly labeled tropical species.

Famed botanist Joseph Rock began planting the campus grounds in the same year, and in 1920 mapped 560 plants on the campus. Many of those first trees remain on campus, as the core of our remarkable collection.

In 1975 the Ad Hoc Committee on Preservation of Campus Plantings, considering that the "old campus ewa of Hawaii Hall was designated an arboretum sometime in the second decade of the university," accepted a proposal "that the entire campus should be designated as the Rock Memorial Arboretum," although this was never formally implemented.

Complementary Arboreta

Many universities have associated arboreta a bit removed from campus, and in this context, the University of Hawai‘i is fortunate to have Lyon Arboretum in the back of Mānoa Valley, where UH students and faculty can work in close association with the great staff there. The environment at Lyon is substantially different from that on campus (receiving nearly four times the amount of rain!), and the horticultural history and the arrangement of plantings is also quite distinct.

A growing number of schools also manage their campuses themselves as arboreta, and it makes good sense that UH does this as well, in order to locate on campus a number of essential arboretum activities:

  • Teaching & Research: providing an outdoor laboratory for use by faculty and students in a broad range of subjects including botany, horticulture, ecology & conservation, field biology, natural history, art, Hawaiian studies, landscape architecture, museum studies, design and sustainability.
  • Collections: maintaining, developing and interpreting well-documented plant collections for teaching, research, public education and enjoyment; and providing an opportunity for documented academic collections to be maintained and studied for years to come.
  • Recreation: providing a place where people from the University and the community may gather and enjoy quiet recreation, and where they may come to learn, reflect and renew themselves through contact with the natural world. The Arboretum enhances the quality of life both for the University and the citizens of Hawai‘i.
  • Public education: providing programs about tree care, sustainability, conservation, horticulture, gardening, botany, design and natural history which enhance people's understanding of the natural world.

Our Campus Arboretum is accredited through the Morton Arboretum's ArbNet program. Being part of a national network of campus arboreta helps bring greater recognition to our exceptional collection, and facilitates collaborative scholarship and the exchange and conservation of interesting plants. Examples of other schools with campus arboreta include the state universities of Arizona, New Mexico, Georgia, Connecticut and Maine. The Campus Arboretum serves as a gateway to introduce people to the remarkable qualities of trees, which they can further explore at Lyon Arboretum, also accredited through ArbNet.

A "Tree Campus USA"

The combination of our beautiful trees, the care that we give them (outlined in our Tree Care Plan), and the participatory events on Arbor Day and other occasions, also qualifies UH Mānoa as a Tree Campus USA, recognized by the Arbor Day Foundation.

Mission and Objectives

The mission of our Campus Arboretum is to

Develop the landscape potential of unique woody flora of the tropics on the UHM campus by serving as a living laboratory for education and research, encouraging use by the broader community, and supporting service activities of the University of Hawai‘i.

Our objectives are

  1. To preserve and care for the trees currently inhabiting the campus landscape.
  2. To preserve and expand the species diversity represented in the campus landscape.
  3. To maintain a succession plan for campus trees.
  4. To continue and to improve the use of the campus as an arboretum for research, teaching and public education.
  5. To increase the extent of the campus tree canopy to achieve aesthetic, design, and environmental benefits.
  6. To celebrate trees through events within the campus arboretum and in the surrounding community.
  7. To provide service learning opportunities for campus constituents.
  8. To maintain documented academic collections over time.
  9. To maintain records of all plants in the campus collection.


Arboretum development is overseen by the Campus Plants Collections Committee (CoCo), and implemented by the department of Buildings and Grounds Management (BGM), which provides the necessary labor and staff, and oversees volunteer plantings and other activities.

On special occasions, the Campus Arboretum offers guided tours of the campus plant collection. These tours take place before 10 am or after 4 pm in the winter, and before 9 am or after 5 pm in the summer, to take advantage of the “golden hour” and the cooler times of the day.

BGM maintains records of arboretum trees in our GIS inventory, documenting many attributes of each tree, including species, approximate age, and condition. The inventory links to the permanent vouchered dried-plant, seed, and DNA tissue reference collections maintained at the Joseph F. Rock Herbarium in St.John, which also manages the Hawai‘i Seed Bank, providing a permanent ex situ repository for long-term storage and conservation of seeds for future replanting of species growing on the campus landscape.

The Collections Committee, in partnership with the Landscape Advisory Committee (LAC), University of Hawai‘i Foundation (UHF) and the Office of Planning and Facilities (OPF), is responsible for developing short-term and long-term operational plans for the Campus Arboretum, and adjusting them as needed for integration with the Landscape Master Plan, and the best future for our campus plants.

Poster presented at the American Public Gardens Association (APGA) 2008 Meeting

Read our blog!

Contact Us

Landscape Services

2002 East-West Road

Honolulu, HI  96822

ph: 808.956.4626

fx: 808.956.4075

Related Links

Click here to login to AiM