Plant Disease Management Handbook

Cause Butterfly bushes (Buddleja sp.) are generally disease free, however, a few pathogens have been found in the PNW. The leaf spot disease caused by Cladosporium herbarum has been reported from Washington and found by the OSU Plant Clinic.

The OSU Turfgrass Disease Diagnosis Laboratory provides quick and accurate diagnostic information and management recommendations for turfgrass problems. This diagnostic lab supports golf courses, commercial turfgrass managers, and homeowners.

Diagnostic services include: visual diagnosis, microscopic examination, pathogen culturing, disease management recommendations, diagnostic results via phone or email, and a full diagnostic report available with an additional fee.

Pathogen identification via single gene sequencing


This service identifies purified plant related bacterial or fungal cultures using single gene sequencing (e.g., ITS or 16S). ID will be to species when possible, but it may be necessary to sequence additional gene regions to arrive at a clear identification.

Cause There are many different organisms that can cause leaf spots on penstemon. Puccinia palmeri and Puccinia pentstemonis are rust fungi that has been reported on penstemon throughout the PNW. A few other Puccinia species have also been reported from WA. Ramularia nivosa is common on penstemon species and reported throughout the PNW as well.

Photinia-Crown Gall

The University of Idaho Department of Entomology, Plant Pathology and Nematology offers diagnostic services for plants at the Parma and Idaho Falls research and extension centers. We have state of the art labs offering a range of diagnostic tests from culturing to molecular diagnostics. We will also investigate the cause of various plant problems on a range of hosts and provide advice for disease management. Both labs are part of the National Plant Diagnostics Network (NPDN) and adhere to the procedures and reporting requirements required of member labs.

By C. M. Ocamb

By C. M. Ocamb