Brandon Au

Managing Oahu’s Urban Forest


The City & County of Honolulu is committed to planting 100,000 trees across the island of Oahu by 2025 and to increasing the urban tree canopy cover to 35 percent by 2035. One of the City employees helping to attain those goals is Unit 13 member Brandon Au, a certified arborist and park grounds improvement supervisor in the Department of Parks and Recreation’s Division of Urban Forestry (DUF).

“Having trees in our urban areas provides the most benefits to the environment and for everyone,” says Au. “Living in an urban forest makes it a challenge for trees to thrive and survive in the surrounding hardscape. We must do our job to keep trees alive and healthy.”

Most residents living on Oahu may not know there are people like Au and the rest of the team of City DUF workers who every day cultivate and manage trees on the island to benefit residents’ overall good health, beautify our city and lower increasing temperatures due to global warming. The DUF manages over 240,000 trees on Oahu, the largest inventory of trees managed by an entity in the urban environment.

Au has been with the City for nearly 18 years, starting out as a nursery worker before being promoted to park grounds improvement supervisor, overseeing the Nursery and Landscape Section of the Horticulture Services Branch. Prior to graduating from college with a business management degree, Au worked in the nursery and landscape industry but did not plan to pursue it as a career. However, his passion for trees and plants helped keep him on that path.

That passion, along with his expert knowledge and experience, has not gone unrecognized. Called “truly irreplaceable” and “one of the most respected arborists in the division,” Au was named the Department of Parks and Recreation’s Employee of the Year in 2018. In his nomination for the award, it was written: “Brandon is the go-to-guy when it comes to conducting inspections of tree plantings and landscape planning. This duty involves reviewing plans, contracts and site visits for developments in public, private and residential sectors. As a result, there is no limit to the type of organization or person with whom Brandon can effectively work with.”

As a certified arborist at DUF, Au manages the City’s tree inventory along City roads and in City parks, oversees private contractors working on trees, consults various government agencies in tree preservation and protection, and reviews tree health assessments submitted by private arborists. “You can almost call me a tree doctor,” he says, jokingly.

Au, along with fellow City arborists and other supporters of Trees for Honolulu’s Future, a nonprofit organization, are part of the City’s initiative to ensure a more sustainable and resilient future for Oahu. “The work that we do may not seem important as trees cause inconveniences and hardships in terms of maintenance,” Au says. “But we need trees and trees need us to survive. It is our responsibility to preserve as many trees as possible.” Even in his spare time, Au is tirelessly involved in volunteer efforts to keep our future green, working with Landscape Industry Council of Hawaii and conducting training programs for the International Society of Arboriculture and Hawaii Landscape Irrigation Contractors Association.

“Working with dedicated people with high standards and goals makes me want to become better at what I do,” says Au. “I believe we work to strive and improve our City to the best of our capability. So far, it has been a great and challenging experience.”