A disease known as Rapid ‘Ōhi‘a Death (ROD) is killing ‘ōhi’a, one of Hawaii’s most important and abundant endemic trees. First detected on Hawai‘i Island more than four years ago, the disease has impacted more than 175,000 acres of ‘ōhi‘a forest on the largest of Hawai‘i’s islands. More than a million trees are estimated to have died. Scientists have determined that the disease enters the tree through open wounds (made by humans through clippings, trimming, weed whacking, and stepping on tree roots; or other animals, such as rooting pigs; or broken branches and abrasion caused by strong winds/storms). Once the fungal spores enter the trees, the disease advances by cutting off the tree’s flow of water.
Some ways residents and visitors can help prevent the spread of ROD is by following these guidelines:
1) Keep your eyes open. If you see ʻōhiʻa with a limb or crown turning brown, take a picture, and contact KISC via email (firstname.lastname@example.org) or phone (808-821-1490). Samples of the wood must be taken by trained technicians and tested in a laboratory to confirm the presence of the ROD fungi.
2) Avoid injuring ʻōhiʻa. Wounds serve as entry points for the fungus and increase the odds that the tree will become infected and die from ROD. Avoid pruning and contact with heavy equipment wherever possible. If you must work around or cut ʻōhiʻa, clean tools and gear before and after use, especially when used on infected ʻōhiʻa.
3) Clean gear and tools, including shoes and clothes, before and after entering the forest and areas where ʻōhiʻa may be present. Brush all soil off tools and gear, then spray with 70% rubbing alcohol. Wash clothes with hot water and soap.
4) Wash your vehicle with a high-pressure hose or washer if you’ve been off-roading or have picked up mud from driving. Wash the tires and undercarriage of your vehicle to remove all soil or mud.
5) Don’t move ʻōhiʻa wood or ʻōhiʻa parts, including adjacent soil. The disease can be spread to new areas by moving plants, plant parts, and wood from infected areas to non-infected areas. If you don’t know where the wood is from, don’t move it and keep it out of the greenwaste.
6) Don’t transport inter-island. Don’t move ‘ōhi‘a plants, whole or parts, ʻōhiʻa wood, or soil from Hawaiʻi island without a permit. Comply with the new quarantine rule to help prevent ROD from spreading.