Phytophthora ramorum

Department of Crop Sciences
University of Illinois at Urbana-Champaign

Frequently Asked Questions

Don't we already have Phytophthora in Illinois?

Many species of Phytophthora are considered common or established in Illinois, but P. ramorum is not one of them. For example:

Although you may correctly conclude that your rhododendron shows "Phytophthora blight" symptoms, the only way to determine which species is causing the disease is to submit a plant sample for culture or PCR testing.