Sudden oak death pathogen found

By Peter Kent

Clemson scientists have confirmed the first incidence in South Carolina of the pathogen that causes sudden oak death. Called Phytophthora ramorum, the fungus-like organism has killed thousands of oaks and associated plant species in the coastal forests of California and southwest Oregon. It also has attacked ornamental plants in nurseries and landscapes in the United States and Europe.

“One of the major concerns is that the climate here is similar to northern California,” said Christel Harden, assistant department head for Plant Industry, a Clemson regulatory agency that oversees agriculture activities in the state. “If the pathogen takes hold, it could cause significant damage to the forest and nursery industries.”

In South Carolina, forestry is an $835-million industry. Hardwoods cover more than half the state’s 12 million acres of forests. The “green” industry – turf and ornamental crops – is the state’s No. 2 agricultural commodity, valued at $290 million. The disease easily spreads by moving nursery plants that are hosts, including camellias, rhododendrons, azaleas and mountain laurels. Symptoms look like many common plant diseases: leaf spot, tip burn, dieback, leaf lesions and bleeding cankers.

 “Don’t dig up any plants or destroy them until they can be tested,” said Steve Jeffers, Clemson plant pathologist and leader of the monitoring effort. “Report any sick shrubs to the Clemson Department of Plant Industry at 864-646-2139 as soon as possible.”

For information: Christel Harden, 864-646-2139,