A fungus has killed hundreds of thousands of ohia trees across the Big Island, and state officials said Wednesday they are ramping up efforts to prevent it from spreading to other islands.

“The ohia tree is the fundamental tree of the Hawaiian forest,” said Suzanne Case, director of the Department of Land and Natural Resources. “It’s the fabric that holds this great natural diversity together and if you lose this core branch of forest, you’re threatening to lose the integrity of the forest.”

State and federal agencies have partnered with researchers to produce a video and brochures to reduce the spread of “rapid ohia death,” which is caused by a strain of fungus never seen in the islands before.

Suzanne Case discusses how the DLNR plans to address rapid ohia death during a press conference on Dec. 23, 2015.
Suzanne Case discusses how the DLNR plans to address rapid ohia death Wednesday. Marina Riker/Civil Beat

The agencies created a handout that lists things people can do to stop the spread of the fungus, including washing their car, shoes and clothing after going into an area with ohia. Also, not transporting the wood is critical to prevent other trees from becoming infected.

Case said it’s important that the public helps to prevent the spread of the disease.

Right now, state officials don’t know how to treat the fungus, which attacks the tree’s vascular system, halting the transportation of water and nutrients that nourish it.

Then, within days to weeks, the tree dies.

In August, the Hawaii Board of Agriculture approved a rule that banned transporting ohia across the state without a permit. State officials hope that with the public’s help and the new quarantine rule, they’ll be able to buy time enough time to find a cure before the fungus spreads to other islands.    

The DLNR is trying to figure out exactly how many trees are infected. It’s also working with international experts to try to develop a way to stop the fungus.

“There is usually not a simple fix,” said Rob Hauff, DLNR forest health coordinator. “Because the threat is so great, we’re going to try everything possible.”  

If the fungus continues to spread, it could be disastrous for Hawaii’s forests. Ohia trees cover more than 1 million acres statewide, and are considered the most important tree for keeping the state’s watersheds healthy.

The fungus was first noticed in Puna in 2010. Four years later, it was estimated that the disease covered approximately 6,000 acres from Kalapana to Hilo. 

State officials estimate the fungus has infected about 15,000 acres. Researchers have no idea how it entered the state, or where it came from.

Here are five things you can do to prevent the spread of rapid ohia death:

• Don’t move ohia: Do not move ohia wood, firewood or posts, especially from an area known to have rapid ohia death. If you don’t know where the wood is from, don’t move it.

• Don’t transport ohia interisland: Comply with the new quarantine rule.

• Clean your tools: Use only proven cleaning methods. Tools used for cutting ohia trees (especially infected ones) should be cleaned with 70 percent rubbing alcohol or 10 percent bleach (if using bleach be sure to oil afterwards to prevent corrosion).

• Clean your gear: Clean your shoes and clothing. Decontaminate shoes by dipping the soles in 10 percent bleach or 70 percent rubbing alcohol to kill the rapid ohia death fungus. Other gear can be sprayed with the same cleaning solutions. Wash clothing in hot water and detergent.

• Wash your vehicle: Wash the tires and undercarriage of your vehicle with detergent, especially after traveling from an area with rapid ohia death and/or if you traveled off-road.

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