ONTARIO COUNTY, N.Y. — A deadly disease that kills oak trees has arrived in the Rochester and Finger Lakes region.

The state Department of Environmental Conservation is responding to a confirmed report of oak wilt on a private property in South Bristol. The DEC is working to contain the disease's impact before it takes from the region's canopy the way Dutch elm disease, chestnut blight and the emerald ash borer have in the last generation.

"It's a similar threat in that, once these trees are affected with the fungus, they will die," DEC Region 8 Forester Mark Gooding said. "It's a much slower moving issue than some of those in the past, but nonetheless, it will continue to progress."

It's the second case of oak wilt in Ontario County since 2016. The other was found in Canandaigua.

Oak wilt attaches the cells of the tree through the fungus Ceratocystis fagacearum. According to the DEC, the fungus spreads into an oak trees xylem, the water carrying cells of the tree. Oak trees that contract the fungus see their once healthy, green leaves discolor from the edges inward, until the leaves breakaway and fall. 

The Rochester area is home to both red oaks and white oaks. Oak wilt can kill a red oak in weeks to several months. The fungus takes years to overwhelm white oaks.

The disease was first found in the U.S. in the mid 1940's in Wisconsin. It has spread through the Midwest and as far south as Texas.

New York State has been in response mode for oak wilt in recent years when cases were confirmed on Long Island and in the Hudson Valley, near Schenectady. The South Bristol case of oak wilt is the eighth to strike the Empire State.

The disease is spread by beetles that travel from tree to tree, and an oak's own root system. All tree diseases are most frequently spread through firewood. New York State prohibits firewood from being transported more than 50 miles beyond where it is taken. 

DEC responders will continue to monitor the Ontario County cases through aerial surveys and other ground-based responses. Samples taken from South Bristol are due back from the lab in mid-September.

"We enjoy oak trees while we're walking and they're important to our environment," the DEC's Regina Willis said. "They're important to our forest products industry, too. We're working hard to contain this before it grows into something more impactful."