Sudden Oak Death spreading

By Jane Stebbins, Pilot staff writer December 29, 2012 08:47 am

Sudden Oak Death is on the move again, requiring state forestry officials to readjust the quarantine boundary in Curry County.

According to Jim Young, Coos District Forester with the state forestry department, the new site is east of the existing quarantine boundary – and on U.S. Forest Service land.

A public hearing will be held at 7 p.m. Jan. 24 in the Chetco Community Public Library meeting room to discuss the proposed boundary changes.

Forest Service officials are aggressively treating that site and any others outside the existing boundaries. Treatment usually includes a “hack and squirt” method that kills the trees within 300 feet of the infected tree, preventing tanoaks and other host species from resprouting later. Dead trees are then piled up and burned.

Priorities, Young said, dictate funds no longer be spent on heavily infested areas to the south and west.

The “general infested area” extends from south of Harbor, then inland about 1.5 miles to the Chetco River, heads northeast to cross the North Fork of the Chetco River, then straight north until it jogs west to Bowman Creek.

The quarantine area includes that area and extends farther south to just north of the Winchuck River, then north, doglegging west to a location where two infected trees about 3 miles north of Cape Sebastian were discovered in 2011.

The new discovery of infected tanoak, however, is east of the quarantine area, requiring the boundary to be extended south and southeast to include the new site and another 3 miles beyond it as a buffer.

“It’s spreading, but slowly,” Young said. “We’re trying to keep it in the quarantine area, and we’re treating sites, but we don’t have the money to treat everything within the boundaries. We have to prioritize the sites we treat, keep it contained.”

Sudden Oak Death (SOD) is caused by the pathogen Phytophthora ramorum. The pathogen infects the trunks of trees — or the leaves in tanoak trees — killing most of them. It can also infest Douglas fir, coast redwood, madrone and others, but they are usually infected on leaves and twigs, and known as the non-lethal Ramorum blight.

SOD, an invasive species, appeared in southwestern Oregon at the turn of the century and has slowly been making inroads north.

“Early on, we had hopes we could eradicate it,” Young said. “But the cost was prohibitive.”

Most funding is obtained through Forest Service grants, and the state is working to obtain more, he said.

The pathogen is more prolific in the spring when it is wet from seasonal rains and temperatures are on the rise.

“The Brookings area has the perfect climate for that pathogen; it’s kind of balmy down there,” Young said. “It has perfect conditions for Sudden Oak Death, unfortunately.”

No rules or regulations will be changed when the boundary is adjusted. People are asked to avoid quarantine areas and refrain from removing material from the woods to prevent its spread. The proposal would clarify the definition of  a “disease-free area” and reference a new federal order for infected nurseries.

Hunters, campers and others using store-bought firewood are urged to “burn it where you bought it” to prevent the spread into uninfected areas.

The maps outlining the “general infestation area” and the existing quarantine area can be found at www.oregon.gov/odf/privateforests/docs/fh/sod_quarantineareacurryco.pdf.