Aggressive strain of rapid ohia death detected at Kalopa State Recreation Area

KAILUA-KONA — Rapid ohia death has been detected in trees at Kalopa State Recreation Area on the Hamakua Coast.

During a regularly scheduled quarterly aerial assessment of forests on Hawaii Island in late July, spotters detected more trees “symptomatic” for the presence of C. lukuohia, the fungus more commonly known as rapid ohia death, in the Kalopa State Recreation Area, according to a Tuesday news release from the state Department of Land and Natural Resources.

After the helicopter surveys utilizing digital mobile sketch mapping, ground crews from the Big Island Invasive Species Committee followed up by taking ground samples.

“This detection is roughly 12 miles from the nearest known occurrence of the fungus on the east side of the island. We sampled three trees in the recreation area and three trees in the adjacent forest reserve,” said Bill Buckley of BIISC.

Five of the six samples tested positive for C. lukuohia, one of a pair of fungi associated with rapid ohia death and the most aggressive of the two, according to the DLNR.

“We continue to take samples and are conducting UAV (drone) flights to more accurately map the area. We’re working with the DLNR Division of State Parks to determine next steps which could include felling the diseased trees,” said Bill Stormont of the DLNR Division of Forestry and Wildlife. “This is desirable to limit the potential spread of the disease by dust and frass created by beetles that burrow into infected trees.”

Tree felling only happens if it can be done safely and without harming surrounding trees. It’s ideally done on a rainy day to limit potential airborne dispersal of the fungus, according to the DLNR. Felling would only happen in the park and not in the adjacent forest reserve, where the tree canopy is too tight to make cutting trees a viable option, DLNR said.

Kalopa State Recreation Area has been closed since mid-July for repairs and upgrades to the park’s cabins and campgrounds. The projects are not expected to be complete until May 2019.

The DLNR said it is in discussions with an adjacent private landowner to gain access to sample symptomatic trees on that property. Based on on-going aerial surveys, it’s estimated 135,000 acres of ohia forest on Hawaii Island currently show symptoms of the disease.

Earlier this year, according to the DLNR, the less aggressive strain of the fungus was detected in a relatively small stand of trees on Kauai. So far, it has not been discovered on Maui or on Oahu, but regular surveys continue statewide.