The C. Wayne Ellett Plant and Pest Diagnostic Clinic specializes in the identification of plant diseases, plant health problems, insects and insect related problems. 

The CWEPPDC is a member of the National Plant Diagnostic Network. The clinic offers a broad spectrum of testing to identify pests and plant diseases.  Diagnosticians collaborate with specialists in plant pathology, entomology, horticulture, agronomy, natural resources, and other areas to identify pests, plant diseases, and cultural and environmental problems of plants. The C. Wayne Ellett Plant and Pest Diagnostic Clinic is a fee-based service laboratory.

The PPDC accepts samples from the following clients:
Commercial production: vegetable, floriculture, ornamental, fruit, hops, and field crops.
Commercial landscaping companies and arborists: tree care, public parks/gardens, landscape management
Residential: homeowners or backyard gardeners, landscape ornamentals

PPDC is not a medical facility. We cannot accept samples from a person's or animal's body.



  1. Important Sample Submission Update

    Oct 28, 2022

    Good afternoon, clients of the Plant and Pest Diagnostic Clinic. We are excited to announce that we are now accepting diagnostic samples at our Wooster location.

    The Clinic will process samples from commercial production (vegetable, floriculture, ornamental, fruit, hops, and field crops),  from commercial landscaping companies and arborists, and from non-commercial and landscape clients (homeowners or backyard gardeners, landscape ornamentals),

  2. COVID-19 Late Summer Update

    Aug 27, 2020

    Beginning August 27, 2020, we are now accepting samples by mail or in person. In accordance with state and local restrictions, please wear a face covering if entering the building or meeting with the diagnosticians outside of the building.

    We can also accept digital samples of plants or insects submitted via email, and we will make our best efforts to diagnose or advise you based on the digital information. Our fee for digital sample diagnosis is $20.00.

  3. The Clinic will no longer accept any samples that contain any material that does not originate from plants or insects

    Feb 12, 2019