UC Nursery and Floriculture Alliance
University of California
UC Nursery and Floriculture Alliance

Fall 2013: Research Update

CAMPUS RESEARCH UPDATE: National consortium at NORS-DUC studies Sudden Oak Death in quarantine nursery facility

by Karen Suslow

The National Ornamentals Research Site at Dominican University of California (NORS-DUC) is the only established field research facility in the country designed to study regulated plant pathogens in a secure environment. Funded by the USDA Farm Bill, NORS-DUC focuses on systems approaches for nursery production and on developing science-based best management practices and risk mitigation to exclude, contain and control the regulated pathogen Phytophthora ramorum, causal agent of Sudden Oak Death, from the nursery production chain through investigations conducted by a national consortium of experts. Research outcomes will be used to develop appropriate standards and procedures to advance best management practices for P. ramorum and to provide viable options for the nursery industry to remediate contaminated soil in retail, wholesale or landscape environments. To facilitate improvements in plant trade, nursery managers and growers will continue to receive training for appropriate control measures to advance industry safeguards for production at the state and national level.

Phytophthora ramorum is a pathogen on track to impact the nursery industry’s national and international market beyond that of any other plant disease. NORS-DUC offers an unparalleled opportunity to study the epidemiology of P. ramorum diseases of ornamentals in a nursery setting that has not been accomplished previously. Thus, research at NORS-DUC realistically addresses the threats of this pathogen to specialty crops which cannot be accomplished in this manner with this disease anywhere else in the United States.

Research successes at NORS-DUC are the direct result of the development of a sophisticated, quarantine facility where realistic nursery studies are possible and where well-designed, successful research projects are being conducted by expert scientists.NORS-DUC is on target to contribute substantial impacts to the nursery industry and enhance plant trade. For the past eleven years, P. ramorum has been impacting US nursery trade. Just within the first two and a half years of active NORS-DUC research, two green technology P. ramorum soil remediation deliverables have been researched, developed and approved by USDA APHIS and are viable options for contaminated nurseries (on a case-by-case basis) in order to eliminate or kill P. ramorum in the soil substrate.  Both technologies (steaming and the use of a biological control agent) have been successfully tested at a contaminated retail nursery and at a contaminated wholesale nursery in California.  Success has led to the release of the wholesale interstate shipper from the Sudden Oak Death federal quarantine.

Technology transfer of these NORS-DUC successes to a wider national nursery audience is underway in a multi-state Farm Bill proposal spearheaded by Oregon Department of Agriculture, Washington State Department of Agriculture, Washington State University and California Department of Food and Agriculture. This multi-state proposal has been accepted to establish proof of concept in nursery settings under varying climatic conditions and varying soil types. Additionally, a third green technology research project for soil decontamination using soil solarization appears highly promising, and NORS-DUC researchers and staff continue to address those specific priorities. The nursery industry had identified the remediation of the contaminated soil substrate as the number one priority for the industry nationwide.

NORS-DUC continues to identify, prioritize, facilitate and conduct research related to pests and diseases of nursery stock while safeguarding plant health and the environment. The current Phytophthora ramorum research successes at NORS-DUC illustrate NORS-DUC’s potential to provide long-term solutions for P. ramorum and demonstrate NORS-DUC’s capability to address regulated plant pests and pathogens that threaten the nursery trade. NORS-DUC is laying the foundation for future work on pests of quarantine significance nationally.  The NORS-DUC is a flexible, state-of-the-art lab and nursery research facility that is capable of adapting to the needs of the nursery industry to address pests of concern.


Karen Suslow is Program Manager and Principle Investigator, National Ornamental Research Site at Dominican University of California. You can reach Karen at karen.suslow@dominican.edu.

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