A Message On Service Changes

The PDDC continues to have limited capacity to process physical samples.  Visit our Services page for details on the clinic’s current submission process.  Last Update:  January 6, 2023.

The PDDC will continue to rely heavily on making digital diagnoses.  Visit our Digital Diagnosis page to submit your photos.  There is a $20 fee for digital diagnostics.  For a complete list of fees, visit our Fees page.

If you are from outside Wisconsin, please contact the PDDC *before* you submit a sample.

Plant Disease Diagnostics Clinic Mission

Alternaria Leaf Spot of American GinsengThe University of Wisconsin-Madison/Extension Plant Disease Diagnostics Clinic (PDDC) provides assistance in identifying plant diseases and provides educational information on plant diseases and their control.

PDDC clients include agricultural and horticultural producers (e.g., farmers, nursery owners), agricultural and horticultural professionals (e.g., crop consultants, arborists), home gardeners, Extension staff and Master Gardener volunteers, and state and local government (e.g., Wisconsin DNR, city and county foresters).

While the Plant Disease Diagnostics Clinic focuses on plant disease problems in the state of Wisconsin, any interested party is welcome and encouraged to take advantage of and participate in the Clinic’s educational services and activities.

If after exploring this website, you have questions about PDDC services feel free to contact the clinic at 608-262-2863 or bdh@plantpath.wisc.edu.

Plant Disease Talks

PDDC Plant Disease Talks

Each month in 2023, the UW Plant Disease Diagnostics Clinic will sponsor a Zoom
presentation on a plant disease-related topic.

Visit our Plant Disease Talks page to learn more.

Plant Disease Talk Icon


December Events

December Pine Tree Icon

Ten Cool Plant Diseases You Can Learn to Love
(and Identify by Eye)
(2023 PDDC Plant Disease Talks)
December 13, 2023
6:30 – 8:30 PM
Statewide via Zoom
Register Here

Limerickettsia Book

Check out our new Limerickettsia book!

Limerickettsia Book at an Angle

Disease Medallions

Learn about our new UW Plant Disease Facts Medallion Project.

Come back often and check for new medallions as they become available.

Sample Medallions

Medallion Samples

Click the image to open an enlargement in a new window.


University of Wisconsin-Madison