Pathogen Alert on Woody Ornamentals

by Gary W. Moorman, Prof. of Plant Pathology at The Pennsylvania State University, Dept. of Plant Pathology & Environmental Microbiology

ATTN: All who deal with woody ornamentals

Phytophthora ramorum, the pathogen involved with Ramorum Blight/Sudden Oak Death was detected in plants (among a total shipment of 52,000 plants) shipped to PA from a nursery in Oregon. A mix of rhododendrons and other plants were sent to ‘big box stores.’ The PA Dept. of Ag is initiating a trace forward effort to try to find plants that may be infected, immediately starting with the big box stores. It is likely that some of the plants from that shipment have been sold.

Any commercial nurseries, landscaper, etc. concerned with this issue should contact a PDA inspector or the Bureau of Plant Industry directly in Harrisburg and send samples via that route.

Any homeowners concerned with this issue may contact Cooperative Extension and arrange to send a sample to the Plant Disease Clinic. CONCERN ABOUT P. RAMORUM SHOULD BE NOTED ON THE SAMPLE. It is not practical to test every sample for P. ramorum. Therefore, give Sara May a ‘heads up’ on pertinent samples. For detailed info about the Penn State Clinic, see: Gary Moorman can be reached at

More information will be forthcoming, including fact sheets from PDA. Just be aware that there is a problem and that you may be receiving questions from clientele about this issue.