These are just some of the many places that KMWP works within the 100,000+ acres of the Koʻolau Mountains. KMWP work includes invasive, non-native plant species removal and control, fence line construction, bio surveying and community outreach. Through our efforts, we help to maintain the resiliency of our native forests in the Koʻolau.
Kaluanui Natural Area Reserve, under management of DLNR, includes 375 acres of some of the best native forest remaining on Oʻahu. Directly mauka of Sacred Falls State Park, this remote area of the Koʻolau Mountains is often shrouded in cloud. The vegetation at Kaluanui is primarily low-growing ʻōhi‘a forests and dense shrublands that include kōlea (Myrsine spp.), lehua papa (Metrosideros rugosa), ʻōhi‘a hā (Syzygium sandwicensis) and ʻuki (Machaerina angustifolia). Because of its elevation and isolation, much of this forest is relatively weed-free. However, invasive species such as strawberry guava and giant fern (Angiopteris evecta) are present and must be controlled to prevent them from destroying this unique ecosystem. KMWP is assisting DLNR to fence Kaluanui to prevent pigs from damaging the fragile mauka shrublands.
Oʻahu Forest National Wildlife Refuge
The Oʻahu Forest National Wildlife Refuge is managed by the U.S. Fish and Wildlife Service (FWS). Because the unit is very large, spanning almost 4,700 acres from the summit of the Koʻolau Mountains to Mililani Mauka, KMWP focuses its attention on the invasive plants that pose the greatest threat to the most intact native habitats, partnering with FWS staff. Top targets are Himalayan ginger (Hedychium gardnerianum), albizia (Falcataria moluccana), and manuka (Leptospermum scoparium). Another target is manuka (Leptospermum scoparium), which is spreading into native forest along the eastern boundary of the refuge. Another project has resulted from a fire in January 2015 in the lower part of the refuge that burned ~400 acres of mostly native forest. KMWP and FWS are developing a restoration plan to ensure that invasive weeds do not spread throughout the burned area and prevent native forest recovery.
Waiʻālae Nui is located in the southeastern section of the Koʻolau Mountains, with Mau‘umae Trail running along its western boundary. The mid and higher elevation forest at Wai‘ālae Nui is largely intact and is dominated by koa (Acacia koa), ʻōhi‘a (Metrosideros polymorpha) and uluhe (Dicranopteris linearis), a common but important fern that helps shield steep slopes from erosion. KMWP partners with the landowner, Kamehameha Schools, to control invasive weed species including African tulip (Spathodea campanulata), guava (Psidium guajava), giant fern (Angiopteris evecta), and octopus tree (Schefflera actinophylla).
The forests in the mauka regions of Waiawa in the central Koʻolaus comprise some of the most important watersheds on the island of Oʻahu. KMWP partners with landowner Kamehameha Schools to control invasive plants on the leeward slopes of the Koʻolau summit, where the vegetation is composed of diverse low-stature native shrublands. Target weeds at Waiawa include albizia (Falcataria moluccana), manuka (Leptospermum scoparium), giant fern (Angiopteris evecta) and octopus tree (Schefflera actinophylla).
The upper elevations of the Poamoho section of the Ewa Forest Reserve contain important native-dominated forests and shrublands, and part of the area is being designated as a Natural Area Reserve. KMWP is assisting DLNR’s Native Ecosystems Protection and Management staff with landscape-scale control of giant fern (Angiopteris evecta) in the mauka sections of the unit. This tree fern has the ability to greatly modify native watershed, turning species-rich shrublands and forests into habitats that are dominated by this one invasive plant. The mauka section of Poamoho is being fenced to stop damage from feral pigs, so that Hawaiʻi’s people can continue to use and enjoy these beautiful intact native montane forests. KMWP is partnering with public hunters and DLNR staff to remove pigs from within the fence.
Helemano adjoins the Poamoho section of the Ewa Forest Reserve. A primary focus of KMWP’s work at Helemano is controlling manuka (Leptospermum scoparium), a highly invasive small tree from New Zealand and southeast Australia. This multi-year project has successfully controlled the majority of the mature trees. In addition, KMWP is partnering with the Oʻahu Invasive Species Committee and DLNR’s Native Ecosystem Protection and Management staff to prevent the spread of cane tibouchina (Tibouchina herbacea). This species belongs to the melastome family, which includes some of Hawaiʻi’s worst weeds, such as clidemia and miconia.