Deal protects unique Kaua'i wetland, home to native plants
By Jan TenBruggencate
Advertiser Science Writer
LIHU'E, Kaua'i — A new agreement between The Nature Conservancy of Hawai'i and Alexander & Baldwin will protect a spread of low-growing native bog plants, including a spectacular lobelia variety with 4- to 5-foot-tall spikes of purple flowers.
Photo courtesy Nature Conservancy
The Kanaele Bog is the state's only mid-elevation bog that retains a mostly intact collection of native plants. The flat, 80-acre area lies 2,100 feet above sea level and gets 160 inches of rainfall annually.
Among the rare native plants that make their home in the Kanaele Bog above Kalaheo is Lobelia kauaensis, with spikes 4 to 5 feet tall. The Nature Conservancy of Hawai'i has signed an agreement with landowner Alexander & Baldwin to protect the bog.
Viewed from above, its vegetation is shrubby and dotted with pools of water stained dark as tea from steeping in aged leaves and branches.
Up close, it is a botanical wonderland.
"Kanaele is an ecologist's gem," said Sam Gon, director of science for The Nature Conservancy. The shallow soil and wet conditions support a range of unique plants, many of which evolved to suit the difficult conditions.
One is the lehua makanoe, a variety of 'ohi'a that grows as a knee-high shrub, unlike its near relatives that stand as tall trees in many Hawaiian upland forests. There is a native violet, native sedges, ferns and a range of plants that grow as trees elsewhere but are bonsai-size shrubs here.
The bog, above Kaua'i's west side community of Kalaheo, lies higher than Alexander Reservoir, along the west side of the dirt road that leads to the Mount Kahili communication transmission towers.
The conservancy and A&B signed a 10-year memorandum of understanding under which the conservancy will fence the bog to keep out pigs, and conduct weed-control programs to stop the influx of strawberry guava and other invasive plants. The conservancy also may conduct rat control and try to prevent alien insects from damaging native species.
Gon said the agency expects to build a raised boardwalk to allow work crews access without damaging the bog and to allow hunters to traverse the bog on their way to pig-hunting grounds.
Initial expenditures for protection of the bog are expected to run $80,000 to $120,000.
A&B's Alexander Reservoir and the Wahiawa Stream are fed by waters flowing from the bog and surrounding forests, and the company cited its value both as a water resource and an important plant preserve.
"The Kanaele Bog area has long been an important resource for the company as a source of water for our business on Kaua'i. Through the years, we have also learned how distinctive and valuable Kanaele is from a biological standpoint," said A&B Vice President Meredith Ching.
Most surviving native bog habitats in the state are at much higher elevations, from 3,000 to 6,000 feet. Among them are the Alaka'i Swamp on Kaua'i, Pepe'opae and Pu'u Ali'i on Moloka'i, the Hana bogs of East Maui and Pu'u Kukui in West Maui and the Kohala bogs on the Big Island.
Reach Jan TenBruggencate at jant@honoluluadvertiser.com or (808) 245-3074.
