A fungal disease that is killing hundreds of thousands of native trees has entered one of the most pristine native forests in the Hawaiian Islands.

Scientist have confirmed that rapid ohia death has been detected in the Hakalau Forest National Wildlife Refuge on the Big Island, according to the U.S. Fish and Wildlife Service.

Scientists fear the death of ohia trees through the fungus Ceratocystiscould put what once was a common native bird on the endangered species list.

“A lot of common species depend on the ohia,” said J.B. Friday, a University of Hawaii extension forester.

Hakalau Forest project leader Jim Kraus said ohia trees are the foundation of native Hawaiian forests on Hawaii island and throughout the state.

For instance, the iiwi bird depends on the ohia for food and breeding, and 90 percent of iiwi are found on the island, Kraus said.

The Hakalau Forest is also home to important endangered species, including the Hawaiian honeycreeper akiapolaau, the Hawaiian hawk io, the Hawaiian hoary bat and several endangered plants and insects.

Wildlife Service officials do not have an estimate of the number of acres of diseased ohia in Hakalau Forest and are still investigating the extent of its spread, spokeswoman Megan Nagel said.

Since the fungus was confirmed as the cause of rapid ohia death, or ROD, the contaminated area has grown from 15,000 acres in 2014 to an estimated 50,000 acres on Hawaii island.

With beetles sometimes as carriers boring into trees, the ROD fungus clogs the ohia trees’ vascular system, preventing water from reaching the top of the tree. Diseased ohia trees might have branches or entire canopies of dead and brown leaves.

Friday said while scientists are looking at ways to halt the spread, there is no known antifungal injection to kill the ohia fungus.

State and federal officials said the likelihood of infection can be reduced by avoiding the breaking of tree bark, which can spread spores.

If tree bark is likely to be broken and beetles are present, the recommended treatment is to fell and cut infected trees, then cover the wood with tarps to prevent further contamination.

The spread of the disease can also be reduced by cleaning soil off shoes, tools and other gear and spraying 70 percent rubbing alcohol to kill the fungal spores, officials said.