Plant Diseases

Now accepting applications for the 2019 Master Gardener Volunteer Training and Horticultural Proficiency programs!!


The Master Gardener and Horticulture Proficiency program provides Oregonians with education about gardening and horticulture. Read More...

OSU Plant Clinic

Online Resource

The Oregon State University Plant Clinic is a diagnostic facility associated with and housed in the Department of Botany and Plant Pathology. The Plant Clinic has been operational since 1954. As part of the OSU Cooperative Extension Service, the primary mission of the Plant Clinic is educational. Extended education is provided by helping our clients recognize the nature of their plant problem (diagnosis) and by helping them to manage the disease or disorder using proper control methods, including cultural, biological, and chemical measures. Emphasis is on prevention of problems by proper management.

By Melodie Putnam

Pacific Northwest nursery IPM

Online Resource

The PNW Nursery IPM Website is designed to be dynamic, allowing growers and pest management professionals to give and receive information regarding pest activities in nurseries in the Pacific Northwest. Whenever possible, we will provide links and further information for growers on particular pests.
Examples of splitting and shrinkage of cedar shingles.

Care and maintenance of wood shingle and shake roofs


Maintenance is essential for the performance of wood roofs. Roofs need to be regularly cleaned of all leaf litter, conifer needles, and debris to limit the growth of organisms such as mosses and lichens. Cleaning solutions, surface treatments, fungal and moss control materials are also discussed.
Botrytis bunch rot of Chardonay

Botrytis bunch rot of grapes


This brief article provides information about preventing Botrytis bunch in the vineyard.

By Patricia Skinkis

pest detectors refer to their reference guide

Central Oregon Potato Pest Monitoring Program

Online Resource

Potato Patches, a weekly newsletter, is published from late June through mid-September and contains a tabulation of the weekly green peach aphid survey, crop water use information, P-Day accumulation, and timely announcements for central Oregon potato producers.

COAREC Annual Reports: Plant Pathology

Online Resource

Annual research reports from the Plant Pathology Laboratory at the Central Oregon Agricultural Research and Extension Center.

Protect Oregon’s Brassica Crops: ODA’s black leg rules aim to control a disease outbreak


Black leg is a serious disease of Brassica crops that has recently appeared in outbreaks in western Oregon. It threatens Brassica production in the Pacific Northwest. In an effort to manage the...

By Nick Andrews

What's killed my tree?


Are you one of the many woodland owners noticing continued signs of drought on your property? Drought impacts are complex; drought stressed trees become susceptible to insects and diseases that are naturally present (typically at low levels) in our woodlands. Take these four steps to help you identify what factors might be impacting your tree health.

By Norma Kline

Blueberry viruses in the Pacific Northwest and suggestions for their management


The goal of this article is to provide a review of the viruses of blueberry that have been reported in the Pacific Northwest (PNW) and highlight those of major concern in the region. Blueberry scorch virus, Blueberry shock virus, Tomato ringspot virus, Blueberry fruit drop associated virus and Blueberry mosaic associated virus are the major viruses that will be discussed.

Fungicide Groups, Modes of Action & Effective Pathogen Control


Fungicide resistance is a serious problem

By Cynthia Ocamb

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