Dr. J.B. Friday giving a tour at Hakalau Forest, a native Hawaiian forest with ohia and koa.
This week, I interviewed Dr. J.B. Friday, Extension Forester with the University of Hawaii, who is working on efforts to combat Rapid Ohia Death. At this time, reported cases of Rapid Ohia Death have been contained to Hawai’i Island.
What is Rapid Ohia Death (ROD)?
A new disease caused by a fungus attacking ‘ohia trees. Different strains of the fungus, Ceratocystis fimbriata, cause disease on plants worldwide. The strain attacking ohia is genetically distinct and new to science. The fungus grows in the sapwood of infected trees, so moving firewood can spread ROD, as well as ohia seedlings, chips, mulch, and soil from infected forests.
Cross section of an infected ʻōhiʻa showing the characteristic dark staining of sapwood caused by Ceratocystis. From RapidOhiaDeath.org
Why should we be worried?
Ecologically, ohia is the most important tree of the native Hawaiian forest. Ohia is more common than all of the other tree species, like koa and iliahi, put together.
What makes ohia special to Hawaii?
Ohia can thrive at sea level, as it does in coastal forests in the Puna district on the Big Island, on the high, dry slopes of Mauna Kea, Mauna Loa, and Haleakala, in the wet forests of Kokee on Kauai where it rains up to 30 feet a year, and on the dry leeward Kona districts where it gets only ten inches a year. We hope that in all this genetic diversity there are genes with resistance to Rapid Ohia Death.
What is being done to prevent the spread of Rapid Ohia Death?
Because the disease is most likely being spread by people, we are working with forest industry, nurseries, and the public to educate people to not move infected ohia and to clean tools used to cut infected ohia. Hawaii Dept. of Agriculture placed a quarantine on the Big Island so it is illegal to transport any form of ohia – wood, firewood, posts, leaves and flowers – to neighbor islands without inspection and a permit. We are also working on methods to treat ohia lumber and flooring products.
How is the disease impacting the forest and animals that live there?
Sadly, when ohia trees die in lower elevation forests they are replaced by alien species such as strawberry guava, Melastoma, Coster’s curse, and maile pilau. If we lose the native ohia forest, we lose most of the native plant, bird, and insect species that go with it.
What can I do to help the spread of ROD?
1) Don’t move ohia wood and live plants.
2) Clean your tools, shoes and gear with 70% rubbing alcohol or 10% bleach.
3) Wash your vehicle if you’ve been near areas with ROD or traveled off-road.
The only way the disease moves is if people carelessly spread it. So far it has only been found on the Big Island.
To learn more, visit RapidOhiaDeath.org
Watch this video and spread the word!!