Phytophthora ramorum

Phytophthora ramorum blight and dieback, also known as sudden oak death (SOD) when it infects oaks specifically, has been detected recently in several sites in the Northwest. For more on this disease and the specific information regarding Phytophthora ramorum in Oregon, check the links.

Training and Information

One of the best sources of training and information on Phytophthora ramorum as well as other species of plant pathogenic Phytophthora species is OSU's Phytophthora Online Course: Training for Nursery Growers.

Recent Events:

California has issued a new report on P ramorum positive nurseries by activity.

Nursery Guidelines have been developed for Pacific Northwest nursery crop producers. One can also refer to the information at the APHIS website: Much information is being developed about this disease and it is recommended that growers periodically refer to the and the plant host list as they will likely be revised over time.

New Federal Order

Plant Health Progress: Sudden Oak Death and Associated Diseases Caused by Phytophthora ramorum. This article has exceptional diagnotic information and images.


Phytophthora ramorum, guide for Oregon nurseries. This Extension publication written by Jennifer Parke, Jay Pscheidt, and Robert Linderman is a great resource for images and current information about this disease on ornamental plants. A "must have" publication for nursery producers wanting to understand this disease.


Oregon State University Extension Online Guide to Plant Disease Control: rhododendron - ramorum leaf blight and shoot dieback. The is site gives general information about SOD and some management information developed for rhododendrons.

Oregon State University's Sudden Oak Death in Oregon website


Oregon Department of Agriculture's Sudden oak death website This includes their P. ramorum free lists nurseries growing host and nonhost materials.

California Oak Mortality Task Force
The most comprehensive informational website on Phytophthora ramorum. Additional information can be found at the Monitoring Sudden Oak Death site.

APHIS Sudden Oak Death site. Here you will find the PPQ list of regulated plants, a Phytophthora ramorum quarantine FAQ, a USDA pdf on symptoms, a color brochure on Sudden Oak Death symptoms.

Nursery Guide for Diseases of Phytophthora ramorum on Ornamentals: Diagnosis and Management

National Ag Pest Information System: Sudden Oak Death

North Central Pest Management Center Pest Alert: Sudden Oak Death. At this website can be found the Phytophthora ramorum Educate to Detect (PRED) program in various formats.

National Pest Alert: Sudden Oak Death fact sheet

Testing Kits

Note: the on-site rapid test kits available at the websites below can detect to the genus level of Phytophthora but not species. Identification to species level can be accomplished at various labs including the OSU Plant Clinic.


Neogen Europe Ltd: Spotcheck or Alert LF Phytophothora information. Another type of rapid test available. They do have a Phytophthora-specific Spotcheck test although it is not currently listed at their website.

Pocket Diagosntic: This company produces the LFD type of test. These tests are easy to use and competitively priced.


Page last modified 3/9/10