Damaging Oak Disease May be Present in Some Alabama Landscapes

The U.S. Department of Agriculture and state and national forestry officials are concerned that the damaging disease, Ramorum blight or sudden oak death, may have been introduced into some Alabama landscapes. Officials say it is possible homeowners may have purchased some common landscape plants in the last few years that may have been infected with the fungus-like pathogen, Phytopthora ramorum, that causes the disease. Ramorum blight was first seen in the 1990s in oak trees in California and Europe.

In 2004, the disease was discovered in four nurseries in California and Oregon. All diseased plants at these nurseries were destroyed, and all diseased plants that had been shipped to nurseries or retail stores in other states were located and destroyed.

In Alabama, the disease was identified in only two nurseries and one garden shop. These plants were destroyed by officials with the Alabama Department of Agriculture and Industries. In all, 22 states found some diseased plants in nurseries or retail garden stores, and, again, all of these plants were destroyed.

Dr. Jackie Mullen, a plant pathologist with the Alabama Cooperative Extension System, says there is concern that some Phytopthora ramorum-infected plants may have been sold before officials were able to visit all the nurseries and garden centers and issue temporary stop sale orders while testing was being done.

Alabama officials do not expect to discover significant occurrence of the disease, because only three positive samples were identified out of 289 samples tested in 2004.

Dr. Austin Hagan, an Extension plant pathologist, says camellias, rhododendrons, pieris, viburnums, mountain laurels and lilacs are some of the common landscape plants that could become infected with this oak disease. These are the common plants that were shipped to Alabama nurseries and garden shops last year from California and Oregon, and symptoms could appear on these plants this spring.

“Other Southeastern plants that may be infected include azaleas, pyracanthas, witch hazels, strawberry trees, poison oaks, honeysuckles, and huckleberries,” said Hagan. “We do not expect to find SOD present in the Southeast on trees at the present time, but trees that are susceptible in this area include the southern red oak and northern red oak.”

Dr. Jim Jacobi, an Extension plant pathologist housed at the Birmingham Botanical Gardens, points out that while the disease has not been found in any landscape settings in Alabama, scientists are establishing a testing program.

“Because of the disease’s severe effects on oak trees, the USDA, the U.S. Forest Service, the Alabama Department of Agriculture and Industries and the Alabama Cooperative Extension System are cooperating to provide a testing program for homeowners if plant damage indicates they may have sudden oak death disease,” said Jacobi. “Several diseases and problems may cause the same type of damage on camellias, rhododendrons and other landscape plants so testing is needed to determine if SOD is present.”

Read Full Story

Dr. Jim Jacobi discusses sudden oak death as well as the screening process being conducted.

Soundbite 1: Jacobi discusses the origins of the disease. 24 secs Download file

Soundbite 2: Jacobi how the disease got to Alabama and the concern it might be present in some landscapes. 37 secs Download file

Soundbite 3: He explains the screening process for homeowners to use. 37 secs Download file

Posted by mlawrenc at May 13, 2005 10:02 AM | TrackBack