The Harold L. Lyon Arboretum features seven miles of trails and the 60-foot Aihualama Falls. The arboretum is conservation land, used for research to find methods to restore native habitat and plants throughout Hawaii. (U.S. Marine Corps photo by Lance Cpl. Suzanna Knotts) - The Harold L. Lyon Arboretum features seven miles of trails and the 60-foot Aihualama Falls. The arboretum is conservation land, used for research to find methods to restore native habitat and plants throughout Hawaii. (U.S. Marine Corps photo by Lance Cpl. Suzanna Knotts)