SALEM (AP) - Sudden oak death - a threat to the state's $800 million nursery crop industry - has been contained on the southern Oregon coast, agriculture officials say.

But the project to eradicate the plant fungus has produced mixed results. A five-year multi-agency effort to completely get rid of the tree-killing disease has not reached its goal, but officials say they are encouraged it hasn't spread far beyond its original detection site northeast of Brookings.

The site has included less than 88 acres of infected plant material, and remains the only place in Oregon where the fungus - Phytophthora ramorum - has been found in the natural environment. “If you look at the results since 2001 when we first found the disease, we have definitely been successful at slowing the spread,” says Dan Hilburn, administrator of the Oregon Department of Agriculture's Plant Division.

“There is no question that had we not done what we have, sudden oak death would have spread throughout the county and would probably be in other Oregon counties by now,” Hilburn said.

The fungus left a trail of dead trees in central and Northern California ever since it was first detected in the San Francisco Bay Area in the mid-1990s. Sudden oak death infects susceptible trees through the bark, killing the entire tree or portions of it.

Ellen Goheen, U.S. Forest Service plant pathologist, was part of the aerial survey that first detected sudden oak death in Oregon in 2001. After seeing tens of thousands of acres of dead trees in California, now spreading over 14 coastal counties, she wanted to keep Oregon from a similar fate.

“We still have the pathogen here, but we have it contained certainly more so than in California,” says Goheen. “I still think we have a good chance of eradicating it from Curry County.”

Certain species of oak commonly found in southwest Oregon, including tanoak and black oak, are very susceptible. But the fungus also infects rhododendron, huckleberry, madrone, myrtle, and several other shrubs.

A policy of cutting, stacking, and burning infected trees and shrubs within the nearly 22-mile quarantined area of Curry County has kept the fungus from spreading. Even though new sites with the disease continue to be found, the numbers are dramatically less than the first couple of years and most infected trees remain within the quarantine boundaries.

“We haven't gotten rid of the disease, but we're still on track of someday perhaps being able to,” Hilburn said.