Karen Ward runs WSU’s Plant Pest Diagnostic Clinic.

Karen Ward runs WSU’s Plant Pest Diagnostic Clinic.

If you find strange rots or spots on your fruit trees or some mysterious ailment, Washington State University’s Plant Pest Diagnostic Clinic is ready to help out.

Karen Ward, clinic coordinator, accepts plant samples for diagnosis of diseases and disorders. The clinic, based in Pullman, serves growers and advisors, as well as the general public, primarily in central and eastern Washington. A second clinic at the Puyallup Research and Extension Center serves western Washington.

Ward said she’s ready to diagnose anything from a common, but unidentified problem to a new, exotic disease. A grower might notice something wrong with his or her cherries and want to find out the cause. The grower might have checked with a horticulturist and still not found out what’s wrong.

She can diagnose plant samples based on visual examination, pathogen culturing, and by using pathogen-­specific test kits. Samples suspected of infection by viruses or phytoplasma are sent to another testing lab. Molecular testing will be available in the future.

Once the problem is diagnosed, Ward can refer the grower or advisor to published recommendations or to an expert who can explain how to treat it.

Ward, who is a plant pathologist with a master’s degree from the University of California, Davis, said growers can also submit insect and arthropod samples, which she will have identified by entomologists.

The cost of a basic diagnosis or insect identification is $25. If pathogen culturing is necessary, the charge is $40.

Samples submitted to the clinic should show the symptoms of concern. They should show various stages of the problem, especially the early stages, which might mean sending several plants. Dead, dry, or decayed ­samples provide insufficient material for diagnosis.

Many problems originate below ground, so roots and soil should be included when possible for more accurate diagnosis.

It also helps to include a description of the tree, site, irrigation, and pesticide and fertilizer use, as well as detailed information about the problem. When was it first noticed? Is it spreading? If so, how fast? How are trees affected?

Ward was plant disease diagnostician at Utah State University in Logan before joining the new WSU diagnostic clinic in 2010. Previously, WSU did disease diagnosis at its Irrigated Agriculture Research and Extension Center in Prosser.

For more information about the clinic and how to package and submit samples, email Karen Ward or phone her at (509) 335-3292.