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Karen Snover-Clift

Karen Snover-Clift

Senior Extension Associate

324 Plant Science Building
(607) 255-7860

I have been the Director of the Plant Disease Diagnostic Clinic of the Department of Plant Pathology at Cornell University since July of 1998 and the Associate Director of the Northeast Plant Diagnostic Network since November of 2002. I was born to diary farming and grew up in New Jersey. I received my Bachelor of Science degree from Cornell in Floriculture and Ornamental Horticulture. I became very interested in plant pathogens during my undergraduate work and decided to pursue a Masters of Professional Studies degree in the department of Plant Pathology. My Masters research focused on an evaluation of onion flower susceptibility to a known fungal pathogen. As Director of the Clinic, I am responsible for diagnosing plant diseases on a wide range of host plants such as woody ornamentals, herbaceous plants, fruits, vegetables, turfgrass, and field crops. Additional duties include training Master Gardeners, Extension Educators, and other green industry members on the basics of plant disease and the pathogens that cause them, as well as introducing youth to the vast world of fungi. As Assistant Director of the NEPDN, I support the overall mission of providing detection of a possible bioterrorist attack of the nation's natural and agriculture systems and lead the network's efforts in implementing a laboratory accreditation program known as STAR-D, the System for Timely, Accurate and Reliable Diagnostics.

Outreach and Extension Focus

As Associate Director of the Northeast Regional Center, a component of the National Plant Diagnostic Network (NPDN), my duties include maintaining a regional center capable of supporting the diagnostic needs of 12 northeastern states. My duties also include close interaction with land grant university diagnosticians, software engineers, university department chairs, and state and national regulatory personnel. I represent all NPDN member diagnosticians on the National NPDN operations committee. As Program Area Manager of the diagnostics committee, I provide leadership in the creation of Standard Operating Procedures, coordination of highly sophisticated, identification procedure training events, and maintaining active communications of significant events. As Program Area Manager of the national database committee, I provide leadership in the creation of Upload Guidelines for those submitting diagnostic identifications to the National Repository at Purdue University and in reviewing the host and pathogen EPA pest codes for appropriate content and accuracy. Serving as the National Quality Manager for the NPDN’s System for True, Accurate and Reliable Diagnostics (STAR-D) requires that I establish a strategic plan and oversee the STAR-D project development, prioritize activities, work with the NPDN executive and operations committees to establish a STAR-D Board, serve as liaison between the STAR-D Board, the auditor team and NPDN diagnosticians, manage the auditors’ preparedness and readiness, develop workshops and training modules to introduce NPDN members to STAR-D components, and provide diagnostic content for the development of the STAR-D documents. My extension teaching programs are geared toward audiences that include Master Gardeners, Extension Educators, other green industry members, and students. They focus on basic plant pathology, plant disease diagnostics, and the operation of the NEPDN. I am responsible for overseeing the diagnosis of plant diseases on a wide range of host plants such as woody ornamentals, herbaceous plants, fruits, vegetables, turfgrasses, and field crops, as well as conducting large scale surveys searching for harmful, introduced pathogens of high concern and those pathogens that are capable of causing significant damage to agricultural or natural environments and may be intentionally or accidentally introduced.

Teaching Focus

Karen's teaching focuses on basic plant pathology and diagnosing plant problems. She often gives guest lectures about basic plant pathology, diagnostic clinics, the National Plant Diagnostic Network (NPDN) and the importance of early detection of high consequence pathogens and pests in courses such in Entomology, Plant Pathology and Horticulture

Awards and Honors

  • NPDN Outstanding Service Award (2016) The National Plant Diagnostic Network (NPDN)
  • Director's Regional Award for Outstanding Service (2012) National Plant Diagnostic Network
  • NPDN Outstanding Team Service Award (2011) National Plant Diagnostic Network

Selected Publications

Journal Publications

  • Snover-Clift, K. L., Clement, P. A., Jablonski, R., Mungari, R. J., Mavrodieva, V. A., Negi, S., & Levy, L. (2007). First Report of the Plum pox virus on Plum in New York State. Plant Disease. 91:1512.
  • Snover-Clift, K. L., & Nelson, E. B. (2001). Abstract: Evaluation of turfgrass phytonematode population distributions on a New York State putting green. Phytopathology. 91:S83.
  • Snover-Clift, K. L., Lorbeer, J. W., & Holcomb, M. A. (1999). Abstract: Onion Seed Infection Levels Subsequent to Sequential Exposure of Onion Seed Stalks and Flower Parts to Aspergillus niger. Phytopathology. 89:S73.
  • Snover-Clift, K. L., Loparco, D. P., & Lorbeer, J. W. (1999). Abstract: Systemic Infection of Onion Seedlings by Aspergillus niger and Fusarium sp. Phytopathology. 89:S73.


  • Snover-Clift, K. L. (2017). A New York State Oak Wilt Project: a few discoveries made and lessons learned. Branching Out Dawn Dailey O'Brien (ed.), Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY, United States.
  • Snover-Clift, K. L., & Dailey O'Brien, D. (2017). First STAR-D QMS Introduction Workshop-A Huge Success! p. 1-3 NPDN News Rachel McCarthy (ed.), NPDN.
  • Snover-Clift, K. L., & Dailey O'Brien, D. (2017). QMS Is All Fun and Games (Well, At Least Partially!). p. 4-5? NPDN News Rachel McCarthy (ed.),.
  • Snover-Clift, K. L., & Dailey O'Brien, D. (2017). QMS workshop participants perform mock audit-an exercise in applying STAR-D principles. p. 3-5 NPDN News Rachel McCarthy (ed.),.
  • Snover-Clift, K. L., & Dailey O'Brien, D. (2017). The First NPDN Laboratory earns STAR-D Laboratory Accreditation. p. 1-2 NPDN News Rachel McCarthy (ed.), NPDN, Ithaca, NY.
  • Snover-Clift, K. L., & Dailey-O'Brien, D. (2016). Fourth STAR-D Phase 2 Training and Gap Audit at the University of Puerto Rico Plant Diagnostic Clinic. p. 5 Rachel McCarthy (ed.), The National Plant Diagnostic Network, Ithaca, NY.

Presentations and Activities

  • Oak Wilt Biology and Background of NYS Identifications. Long Island Oak Wilt Symposium. October 2017. Long Island Oak Task Force. Riverhead, NY.
  • The No Good, Mostly Bad and Very Ugly Plant Diseases Coming through the Cornell University Plant Disease Diagnostic Clinic. Arborists Conference-Fall Meeting. September 2017. NYS Arborists. Liverpool, NY.
  • What is the Impact to New York’s Oak Population? Arborists Conference-Fall Meeting. September 2017. NYS Arborists. Liverpool, NY.
  • Detecting Oak Wilt Using Molecular Techinques. Environmental DNA Workshop. September 2017. Cornell University. Ithaca, NY.
  • Oak Wilt; What Is It? What do new discoveries of this harmful pathogen mean for oaks in New York State? Oak Task Force Meeting. August 2017. Long Island Oak Task Force. Riverhead, NY.
  • Oak Wilt; A Harmful Introduction to New York State. Oak Wilt Workshop. June 2017. CCE Westchester County. White Plains, NY.
  • Oak Wilt…Symptoms and diagnostic methods & the Plant Disease Diagnostic Clinic. NYS Parks Department and Green Wood Cemetery Workshop. April 2017. NYS Department of Environmental Conservation. Brooklyn, NY.
  • Oak Wilt, Sampling Guidelines and PDDC’s Identification Methods. Regional Invasive Forest Pest Outreach Project. April 2017. Integrated Pest Management. Warsaw, NY.
  • Oak Wilt in New York State, Train the Trainer Event. Regional Invasive Forest Pest Outreach Project. March 2017. Integrated Pest Management. Binghamton, NY.
  • Basic Plant Pathology. Master Gardener Training. March 2017. Erie County. Ithaca, NY.