Phytophthora pathogens threaten rare habitats and conservation plantings

  • Susan J. Frankel USDA Forest Service
  • Janice Alexander University of California Cooperative Extension
  • Diana Benner Watershed Nursery
  • Janell Hillman Santa Clara Valley Water District
  • Alisa Shor Golden Gate National Parks Conservancy

Abstract

Phytophthora pathogens are damaging native wildland vegetation including plants in restoration areas and botanic gardens. The infestations threaten some plants already designated as endangered and degrade high-value habitats. Pathogens are being introduced primarily via container plant nursery stock and, once established, they can spread to adjacent areas where plant species not previously exposed to pathogens may become infected. We review epidemics in California – caused by the sudden oak death pathogen Phytophthora
ramorum Werres, De Cock & Man in ‘t Veld and the first USA detections of P. tentaculata Kröber & Marwitz, which occurred in native plant nurseries and restoration areas – as examples to illustrate these threats to conservation plantings.

Author Biographies

Susan J. Frankel, USDA Forest Service

Susan J. Frankel is a Plant Pathologist

Janice Alexander, University of California Cooperative Extension

Outreach Specialist

Diana Benner, Watershed Nursery

Owner

Janell Hillman, Santa Clara Valley Water District

Senior Biologist/Plant Ecologist

Alisa Shor, Golden Gate National Parks Conservancy

Director of Park Nurseries

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Published
2020-02-21
How to Cite
Frankel, S. J., Alexander, J., Benner, D., Hillman, J., & Shor, A. (2020). Phytophthora pathogens threaten rare habitats and conservation plantings. Sibbaldia: The International Journal of Botanic Garden Horticulture, (18), 53-65. https://doi.org/10.23823/Sibbaldia/2020.288
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