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Sudden Oak Death (Phytophthora ramorum)

You may not have heard much about it lately but . . . Keep an eye out for symptoms of Phytophthora ramorum, which causes the devastating disease Sudden Oak Death (SOD).

P. ramorum is not endemic to the Northeast but parts of NYS are considered to be at moderate to high risk for this disease. The most likely source would be infected nursery stock imported into the state. Do you know if the source of your plants has been evaluated for P. ramorum? Ask!

Next ... know the symptoms!

While the disease has a wide host range, most introductions have been on ‘the filthy five’ in nurseries - camellia, kalmia, pieris, rhododendron and viburnum – which get a foliar blight or stem lesions from the pathogen. This is unsightly and may affect the quality of the plants, but the more dangerous effect is that the disease can spread from these plants to oaks and result in tree death.

Plant symptom photos can be found at:

What to do if you think you have P. ramorum in your nursery? Contact your Division of Plant Industry inspector who can help you get an accurate diagnosis.

For more information on the disease and how to manage it,