The Plant Disease Diagnostics Clinic (PDDC) provides assistance in identifying plant diseases and provides educational information on plant diseases and their control.
Each year, the PDDC processes numerous physical and digital photo samples of plants, providing diagnoses of the diseases affecting these plants.
The PDDC is part of the Plant Pathology Department in the University of Wisconsin-Madison, as well as the UW-Madison Division of Extension. The PDDC is housed on the UW-Madison campus in the Russell Labs building.
History
The PDDC was founded by Sr. Mary Francis Heimann, OSF in 1973 to provide support for county UW-Extension agents throughout Wisconsin. Today, the PDDC continues to provide support for the UW-Madison Division of Extension, and also provides diagnostic services directly to citizens of Wisconsin and beyond.
Leadership
The PDDC is run by Brian Hudelson, Director of Diagnostic Services, who earned his BS, MS, and PhD at the UW-Madison. Brian brings many years of experience to the table, and clients throughout Wisconsin turn to him for diagnosis and advice on plant disease topics. A sought-after public speaker and instructor, Brian is known for his down-to-earth style, dry sense of humor, and ability to describe complex scientific topics in relatable terms.
A dedicated teacher, Brian delights in finding innovative ways to engage learners and share his love for plant diseases. Recent projects include:
- designing custom plant disease building block models
- writing a book of limericks on plant diseases
- designing a series of quizzes and custom medallions based on plant disease fact sheets
You can learn more about Brian on the Staff page.
Diagnostic Services
The PDDC provides identification of diseases any type of plant (other than turfgrass) using physical samples and digital photos. The PDDC also provides disease management recommendations. PDDC clients include home gardeners, Master Gardeners, arborists and other landscape professionals, greenhouse and nursery growers, agricultural growers and crop consultants, and students.
Turfgrass diagnostics is handled by the UW Turfgrass Diagnostic Lab.
Outreach/Education
As part of the PDDC’s mission to provide educational information on plant diseases and their control, Brian Hudelson, the PDDC Director, provides a range of outreach activities, services, and resources to the general public throughout the year.
Written Resources
Brian produces informational materials in a variety of formats including fact sheets, web articles, and books. Brian also provides articles and other content for various print and online newsletters including, but not limited to the Wisconsin Crop Manager, Wisconsin Vegetable Crop Updates, Wisconsin Fruit News, Wisconsin Arborist Association Newsletter, and National Plant Diagnostics Network (NPDN) News.
He has also created plant disease-related training modules and podcasts.
Disease Statistics
Brian publishes a weekly report, called the Wisconsin Disease Almanac, that summarizes the plant diseases that he has diagnosed at the PDDC each week.
The Almanac archive goes back to 2013.
Continuing Education
Brian provides numerous presentations and workshops throughout Wisconsin on plant disease-related topics, oftentimes with the sponsorship of local UW-Extension offices, Master Gardener groups, garden clubs, and professional organizations. Brian also provides regular online presentations that are available to citizens of Wisconsin and beyond.
Check out the PDDC events calendar to see if Brian may already be speaking at a location near you. To book Brian to speak for your group, feel free to contact him at (608) 262-2863 or pddc@wisc.edu.
Informational Booths
Brian attends a number of horticulture- and agriculture-related events throughout the year, including the Garden and Green Living Expo. During these events, you can meet Brian and ask him plant disease-related questions. You can find a listing of these events on the PDDC events page.
Mass Media
Radio – Brian appears regularly on Garden Talk with Larry Meiller on Wisconsin Public Radio.
Television – Brian has also appeared regularly on Shelley Ryan’s The Wisconsin Gardener on Wisconsin Public Television.
Online Resources (Social Media and Website)
Feel free to follow Brian on Facebook, Twitter/X (@UWPDDC), or Bluesky to receive updates on PDDC activities and educational resources. If you are not of a fan of social media, but would like to receive PDDC updates, email pddc@wisc.edu and ask to be added to the clinic’s email listserv “UWPDDCLearn”. Also be sure to routinely visit the PDDC website to check on new education materials and opportunities.
College-for-Credit Courses
Brian provides instructional support for several undergraduate courses at the UW-Madison including “Introduction to Plant Pathology”, “Diseases of Economic Plants”, “Capstone in Plant Pathology”, and “Greenhouse Cultivation”.
Learn More
Click the links below to learn more about the Clinic.
- Sample Collection and Submission – Learn how to collect, prepare, and submit digital photos and physical samples.
- Diagnostic Services and Fees – Learn what services we provide, and what we charge for those services.
- Staff – Read the bio of the Clinic’s Director, Brian Hudelson.
- Contact Us – Learn about our hours and how to reach us, and view directions and maps to the Clinic.
- Testimonials – Read testimonials from happy PDDC customers.
- Help Us Improve Our Services – Take our customer satisfaction survey.
- Alphabetical Site Index – A list of all the pages on the site, in alphabetical order. Note: the list does not include Fact Sheets and blog entries.