New threat to Hawaiian trees underscores need for prevention of spread

Guest blog by Faith Campbell with the Center for Invasive Species Prevention

The Hawaiian Islands’ remaining native forests are dominated by the ʻōhiʻa lehua tree (Metrosideros polymorpha). The tree provides nectar for the Islands’ unique honeycreepers- a subfamily of native Hawaiian birds. These birds, the Islands’ one native terrestrial mammal (Hawaiian hoary bat), and many of its endangered plant species depend on ʻōhiʻa-dominated forests. ‘Ōhi‘a also has significant cultural values to the Hawaiian people through its connection to the deities Ku, Pele (volcanoes) and Laka (hula).

‘Ōhi‘a trees on the “Big Island” (the island of Hawaii) are being killed by Ceratocystis Wilt of ‘Ōhi‘a or Rapid ‘Ōhi‘a Death (Ceratocystis fimbriata).  First detected in 2010, the new disease had killed more than half the ʻōhiʻa lehua trees on an area totaling 6,000 acres by 2014. Another 10,000 acres had lower but still significant mortality. The infestation is approaching Hawaii Volcanoes National Park.

At this time, there is no known protective treatment or cure for the disease but thankfully the disease has not yet been reported on any of the other Hawaiian Islands. Because it is not yet known exactly how the disease spreads, to protect the other islands, the Hawaiian Department of Agriculture has adopted an emergency quarantine prohibiting movement of ʻōhiʻa lehua flowers, leaves, twigs, wood (including firewood), mulch, and greenwaste, off the Big Island. To learn more about the specifics of the quarantine, visit: https://hdoa.hawaii.gov/blog/main/ohiaquarantine/

Forestry officials also urge people to avoid transporting wood of affected ʻōhiʻa trees to any new areas on the Big Island and to clean pruning tools, chain saws, vehicles, and shoes used off-road in infected forest areas.  People with homes at higher elevations and on the windward (wet) slopes – such as those living outside Hawaii Volcanoes National Park – do have wood-burning fires, and movement of ʻōhiʻa tree firewood to these homes should be avoided as a precaution. The native forests of Hawaii have many threats to their unique trees – making the need to avoid spreading this new and damaging tree disease all the more important.

  

For more information and complete citations, please visit the Ceratocystis Wilt of ‘Ōhi‘a gallery page