A team of experts is investigating the discovery of rapid ohia death on the northeastern side of Kauai, the first time the disease has been found in trees outside of Hawaii island, it was announced Friday.
The disease pathogen was found in the Moloaa Forest Reserve, prompting officials from state and federal agencies and nongovernment organizations to spring into action last week with a response that included laboratory confirmation, drone and helicopter survey mapping flights, and training for Kauai- based teams on how to identify the fungus and sample for it.
The species, Ceratocystis huliohia, is one of two pathogens causing rapid ohia death across tens of thousands of acres on Hawaii island. It is the less aggressive of the two species.
“If there is a silver lining to this, it isn’t the more aggressive form,” state protection forester Rob Hauff said Friday at a Honolulu news conference. “However, we’re still going to treat this very serious. It’s a new incursion of a tree-killing disease, and we’re going to continue to survey and come up with a strategy about how best to deal with the situation.”
Kauai Division of Forestry and Wildlife botanist Adam Williams discovered at least five trees in the remote forest that appeared to be dead from symptoms associated with rapid ohia death.
Since its discovery on the Big Island more than four years ago, rapid ohia death has been found in more than 135,000 acres of forest, killing millions of ohia trees.
Perhaps 90 percent of the rapid ohia death cases on Hawaii island are affected by the more aggressive pathogen known as Ceratocystis lukuohia.
While a tree infected by a substantial amount of the more aggressive fungus can die in a matter of months, it might take years for a tree under the spell of the less aggressive pathogen. But the outward systems, including brown leaves, look the same no matter which fungus is at work, said Lisa Keith, lead researcher with the U.S. Department of Agriculture.
There is no treatment or cure for the disease, she said.
Sheri S. Mann, Kauai Forestry and Wildlife branch manager, said scientists don’t know how long Ceratocystis huliohia has been on the island, and there’s no evidence it recently spread directly from the Big Island.
“The extent of the infection on Kauai is unknown, which is why more sampling will be done in the future,” she said.
On Wednesday a team from state Department of Land and Natural Resources, USDA, University of Hawaii, Kauai Invasive Species Committee and The Nature Conservancy hiked into the forest reserve to get a closer look at the infected trees.
The pathogen causes a canker disease beneath the bark that spreads slowly throughout the tree, killing off water-conducting tissues. The other species, Ceratocystis lukuohia, is more aggressive and causes a “systemic wilt,” according to the UH website.
Janelle Saneishi, state Department of Agriculture spokeswoman, said the agency is working to expand the existing quarantine restrictions on the transport of ohia from Hawaii island to include Kauai.
To prevent the spread of rapid ohia death, Saneishi said, scientists are asking the public not to transport ohia from Kauai or move ohia wood or parts within the island.
Star-Advertiser staff writer Rosemarie Bernardo contributed to this report.
