The WSU Pullman Plant Diagnostic Clinic is closed as of December 1, 2025. For alternative diagnostic support, please contact your local WSU Extension specialist, Master Gardener Coordinator, or other diagnostic resources, such as:
- WSU Puyallup Plant & Insect Diagnostic Lab – Jenny Glass (jennyglass@wsu.edu,253-445-4582)
- Oregon State University Hermiston Plant Disease Clinic – Dr. Ken Frost or Cassandra Funke (cassandra.funke@oregonstate.edu, 541-567-8321 ext. 120 or (Kenneth.Frost@oregonstate.edu)
- University of Idaho Parma REC Diagnostic Lab – Dr. James Woodhall (jwoodhall@uidaho.edu)
- Richard Old, Weed Identification (rold@pullman.com)
If you need further assistance, please contact Melissa Bills, Administrative Manager for the WSU Department of Plant Pathology (melissa.bills@wsu.edu, 509-335-4852) or Dr. Lindsey du Toit, Chair of the Department of Plant Pathology (dutoit@wsu.edu, 360-848-6140).
The Department of Crops and Soil Sciences contracts with an expert in plant identification. Weed/plant ID samples can be sent directly to the expert at Weed Science.
Samples submitted to the Plant Pest Diagnostic Clinic for identification will be forwarded to the above expert for identification, and the client will be informed of the identity of the plant via the Diagnostic Clinic. Weed control recommendations will not be given with identification.
Weed control information for the home gardener can be found on the WSU Extension Hortsense site. The Pacific Northwest Weed Management Handbook is one resource available to the commercial grower.