Road openings stalled over tree disease fears

Concerns over a waterborne disease that kills Port Orford cedar trees have prompted the Rogue River-Siskiyou National Forest to delay the annual opening of many mountain roads.

Citing one of the wettest springs on record, silviculturist Stephen Boyer said many remote forest roads on the west side of the forest closed off by gates since last fall will not be reopened until the weather turns dry.

Mostly spur roads, they are closed to avoid the spread of Phytophera lateralis, a fungal pathogen which spreads through transportation of infected water, soil and root grafts.

Commonly known as Port Orford cedar root disease, it kills trees from the roots up.

"Wet weather conditions and the resulting condition of forest roads require that the gates remain closed to prevent the spread of the disease," Boyer said. "We will continue to monitor road conditions, and as soon as it dries out for a sustained period of time, we will provide public access."

The closures include many remote roads in the Wild Rivers, Gold Beach and Powers ranger districts. Snow Camp Road, a mountain route between Brookings and Gold Beach, is among the longer stretches among those closed to prevent the disease's spread.

During the wet season, disease spores have been found in mud spattered on vehicles, prompting the annual closures. In addition to closing off roads where the disease has been found, other roads have been closed during the winter to prevent the spread into uninfected areas.

While soil from the tires of motorized vehicles, particularly trucks and off-road vehicles, is believed to have spread the disease, even spores on boots can spread it.

The gated roads are generally open June 1 through Sept. 30.

"We try to keep the gates open when it is dry and close them when it's wet," Boyer said.

Unlike the more common incense cedar, Port Orford cedar — which has both ecological and commercial value — is native only to southwestern Oregon and the northwest tip of California.

It can be identified by the feathery boughs which made it a popular ornamental plant collected by European travelers when they first arrived off the coast aboard sailing ships.

Believed to have originated in Asia, the disease was discovered in the Pacific Northwest in a Seattle nursery in the early 1920s. It began to show up in Port Orford cedar stands in the early 1950s.

Patches of dead, brown Port Orford cedar are now scattered throughout the region.

Although scientists continue to search for a cure, they have discovered seedlings that are naturally resistant to the disease.

Reach reporter Paul Fattig at 541-776-4496 or email him at pfattig@mailtribune.com.