The most exceptional of the Mānoa Campus trees are protected by The Hawaiʻi State Legislature Act 105, which designates an Exceptional Tree as “a tree or stand or grove of trees with historic or cultural value, by which reason of its age, rarity, location, size, aesthetic quality, or endemic status has been designated by the county committee as worthy of preservation.” Through this act, The Hawaiʻi State Legislature recognizes that “beyond their aesthetic worth and cultural significance, trees perform an important role in maintaining ecological balance, in increasing soil conservation and natural oxygen production, as windbreaks for necessary plant species, and in retarding flooding, erosion, siltation, lateral distribution of air pollution, and noise” (State of Hawai‘i Department of Natural Resources n.d.: n.p.).
Act 105 requires each county to establish an Arborist Advisory Committee to research, recommend, and document exceptional trees as well as review actions that may endanger the exceptional trees. Currently, over 150 exceptional trees have been recognized on the island of O‘ahu; eight are located on the Mānoa Campus. Some exceptional trees are also designated as memorial trees based on the significance of the person by whom it was planted. The following list identifies Exceptional trees located on the campus.