Pacific Northwest Plant Disease Management Handbook
National Pesticide Information Center
Oregon State University Herbarium
Plant Clinic @ OSU
Catalogue of Life - indexing the world's known species
USDA ARS GRIN Taxonomy for Plants
International Code of Botanical Nomenclature (Vienna Code)
E-Floras
Northwest Yard and Garden
Plant Database (USDA)
APS Net - American Phytopathological Society
algaeBASE
Planteome
USDA Plant Hardiness Zone Map
Invasive Plant Atlas of the United States
