Walter Mahaffee

Research Plant Pathologist, USDA-ARS & Courtesy Faculty, Dept. of Botany and Plant Pathology
mahaffew [at]

Office: 541-738-4036 x4035

Horticulture Crops Research Lab

3420 NW Orchard Avenue

3420 NW Orchard Avenue
Corvallis, OR 97331

My research focuses on foliar pathogens including powdery mildew and Botrytis, development of disease and phenology based forecasting models, and the development of enhanced disease management practices.

Foliar pathology of horticulture crops: development of biological control systems; ecology/epidemiology of pathogens and biocontrol agents; and integrated pest management.

  • Research focuses on understanding the ecology of microorganisms on plant surfaces, and applying that knowledge to reduce disease development in agronomic settings while enhance the economic and sustainable production of horticultural crops.¬† Current projects include (1) characterize the biology of foliar and fruit pathogens, particularly powdery mildews and Botrytis cinerea; (2) development of technical infrastructure for regional and national disease forecasting systems for plant diseases; (3) use of inoculum detection as a decision aid for disease management, (4) pathogen dispersion and simulation modeling

Research Group Members

Research Assistants/Associates

  • Chris Gorman
  • Tara Neill

Graduate Students

  • Lindsey Thiessen

Profile Field Tabs

Affiliated with: 
Ag Botany / Plant Path
Beyond OSU