The dominant plant life in bogs is grasses and sedges. Some trees and shrubs can grow in this environment, but they are slower-growing in the bog as compared to other places. Often they are dwarfed by the relatively adverse conditions.
Non-grass plants include 'Ohi'a ,
Vaccinium shrubs like 'Ohelo
(related to cranberries), endemic tree-like violets, the bog Silversword
and Dubautia, an endemic genus closely related
to the silversword.
'Ohi'a maka noe, on the left, illustrates the dwarfing of larger plants in bog environments. It rarely grows more than three feet in height. The acid soil may contribute to this. 'Ohelo, on the right, also appears smaller in bogs than in other environments. The photo on the left is by Marilyn Bauer, and the one on the right by Dave Boynton.
Dubautia waialealae na'ena'e
Argyroxiphium caliginis, the bog silversword, is a rare endemic plant found only on Maui. It illustrates the adaptations its genus has made to the various vegetation zones found in the Hawaiian Islands. A close relative, Dubautia waialealea, or na'ena'e, also an endemic, is one of the 21 species found in this genus. As the species name suggests, this plant is found only on Kaua'i. Both photos are by, or contributed by, Charles Lamoureux.
This zone is also coming under attack. The bog on top of Mount Ka'ala in the Wai'anae on O'ahu, shown above, as well as the bogs in Koke'e on Kaua'i, are being attacked by blackberry, carried by hikers as well as pigs and birds. On the left, blackberry peeks out from beneath kanawao on Mt. Ka'ala.
Hikers damage bogs just walking through them. Mt. Ka'ala has a boardwalk which helps to alleviate this problem. Damage by feral pig activity is reduced by fencing.
The picture introducing this vegetation zone is of the trail to Kilohana, at Koke'e on Kaua'i. The boardwalk on the Kilohana trail is under construction. Similar boardwalks can be found in the bogs on Moloka'i.
Conservation organizations, like Sierra Club, which maintains the boardwalk on Mt. Ka'ala and helps control blackberry, and the Nature Conservancy, which has constructed boardwalks on Moloka'i, as well as branches of the State government, are helping to protect this most pristine of all Hawaii's vegetation zones.
