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Joseph O'Brien's Images

Title: Plant Pathologist
Organization: USDA Forest Service
Unit: Forest Health Protection
Country: United States

Joe is a plant pathologist with the U.S. Forest Service in St. Paul, Minnesota. in addition to photography, his major interests include tree diseases in forests, woodlands and urban areas, hazard tree identification and mitigation, and mycology. Joe is a graduate of the University of Michigan (B.S. Forestry and M.S. Forest Pathology) and the University of Minnesota (Ph.D. Plant Pathology), and currently works at the Northern Research Station on the University of Minnesota's St. Paul campus.
Remove Filters: Vascular Wilts(X) Field(X) United States(X) 4 Sizes Available(X) Portrait(X)
19 Images of 4 Subjects View Subject List View Image Details View Thumbnails

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Subject Scientific Name Images
ash yellows phytoplasma Candidatus Phytoplasma fraxini 1
oak wilt Ceratocystis fagacearum 9
sudden oak death Phytophthora ramorum 7
Verticillium wilts Verticillium spp. 2

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