Hawaii’s forests are already in poor ecological condition. Non-native and invasive plants and animals are over-crowding native Hawaiian species. One of the most important native plants in the Hawaiian forests is the ohia lehua (Metrosideros polymorpha). This tree is endemic to Hawaii and provides habitat and food for rare bird species such as the Oahu amakihi and other Hawaiian honeycreepers. Unfortunately, this beautiful tree is in a huge danger, because a newly identified disease started to kill the trees in the Big Island of Hawaii:
Within the past 5 years, extensive ˋōhiˋa mortality has been observed in the Puna District of Hawai‘i Island in previously healthy trees growing in undisturbed forest settings. Affected trees exhibit rapid, synchronized death of leaves on individual branches that eventually spreads to the entire canopy. Dark-brown to black discoloration can be seen in the woody xylem of affected trees… This pathogen poses a serious threat to Hawai‘i’s flagship native tree species whose loss would be catastrophic for the diversity, structure, and function of Hawaiˋi’s remaining native forests and the services they provide.
Scientists determined that the cause of the disease is the vascular wilt fungus, called Ceratocystis fimbriata. It is not yet known what is the origin of this fungus and there is no effective treatment to protect ohia trees from becoming infected or cure trees that show symptoms. Fortunately, the disease has not yet been reported on any other Hawaiian Islands, however it has the potential to kill ohia lehua trees statewide.
Source:
Keith, L. M. et al. (2015) First Report of Ceratocystis wilt on ʻŌhiʻa. Plant Disease, 99(9): 1276.
I photographed this ohia lehua in the Koolau Mountain Range on Oahu, Hawaii.
Gear: Canon EOS 7D, Canon 300mm F/4 L lens, Canon 1.4x extender, Manfrotto tripod
