Rapid ohia death has been detected for the first time on Oahu, state officials reported this afternoon.
The disease was discovered on a dead ohia tree on Kamehameha Schools land in a remote area in the Koolau Mountains above Pearl City.
The find triggered “a rapid response” effort that will include additional helicopter, drone and ground surveys to determine how widespread the disease is, according to the state Department of Land and Natural Resources.
A partnership of state, federal, university, and non-government organizations have been conducting systematic helicopter and ground surveys to look for rapid ohia death since 2016.
Officials said a sample of the ohia tree was analyzed by a U.S. Department of Agriculture lab in Hilo, which confirmed the presence of Ceratocystis huliohia, the less aggressive of the two species associated with rapid ohia death.
On Oahu, 150 dead or unhealthy ohia trees have been sampled for the disease in the past three years, and all have been negative until now, officials said.
The remote location of the infected tree means it is highly unlikely to have been spread by people, officials said.
Researchers are still trying to understand the source of the two Ceratocystis pathogens and are looking at any possible patterns of dispersal.
On Oahu, the ohia tree is found throughout the Koolau and Waianae mountain ranges across some 50,000 acres. The tree serves as a keystone species that helps with recharging the island’s aquifer, providing habitat for endangered species and is used for cultural purposes.