Sudden Oak Death

Ketzel Levine

Plant detective John Griesbach with his beat cops, Katy Betts (left) and Breanne Becher.

Courtesy C. Blomquist, California Department of Food and Agriculture

Infected camellia leaves.

Courtesy of Oregon Department of Agriculture

The disease as it appears on a bigleaf maple.

Courtesy of Oregon Department of Agriculture

The changing face of sudden oak death, on a rhododendron.

Eight years have passed since the plant disease sudden oak death was first detected in California. Now, for the third time since April, it's been found in nursery stock shipped to Oregon. On Morning Edition, NPR's Ketzel Levine goes into the field with John Griesbach, plant pathologist for the Oregon Department of Agriculture, to track down possibly infected plants in some Portland gardens.

The latest infestation involves camellias, one of 22 kinds of plants recognized as hosts for the disease. Other susceptible species, in addition to oaks, include rhododendron, viburnum and Douglas fir.

Sudden oak death (SOD) is caused by the fungus-like organism, Phytopthera ramorum, the origins of which are still unknown. It's a close relative of the disease responsible for the Irish Potato Famine; one of the key differences is that SOD attacks a much wider variety of plants. It's also difficult to identify, as its appearance changes depending on the host plant.

Portland, Ore. residents who bought camellias this year from Kasch's Garden Center are being asked to notify the Oregon Department of Agriculture. The department's number is 1-866-INVADER (usable only in Oregon, Washington, Idaho and Northern California).