Preserves are also an important component of the NTBG . The preserves are seen as a refuge for nature , providing habitat for native and tropical plant species to mature and reproduce in a natural setting without the influence of human activity . They have also provided scientists the necessary means for the reintroduction of critically endangered species that are no longer found in the wild . These preserves act as large laboratories for experiments in conservation biology . The NTBG currently possesses and manages five preserves : the Lawai Preserve ( adjacent to McBryde Garden on Kauai ) , the Ka'upulehu Preserve , which was acquired in the early 1970s on the island of Hawai'i ; the Awini Preserve , which was acquired in 1975 on the island of Hawai'i ; the Kahanu Preserve ( adjacent to Kahanu Garden on Maui ) and the Limahuli Preserve , which was acquired in 1994 on the island of Kaua'i . At present , preserves are not open to the public
Ka'upulehu
Kaupulehu, Hawaii
National Tropical Botanical Garden