Alabama Cooperative Extension System - Publications: Searchable information on diseases of cotton, fruits, ornamentals, peanut, turf, vegetables, and wheat.
North Carolina State University: Notes on disease identification and control for alfalfa, corn, cotton, fruits, nuts, ornamentals, soybeans, tobacco, turfgrass and vegetables.
Ohio State University: Information and control for a range of common diseases.
Oklahoma State University: Description and control of a variety of plant diseases including those caused by insects.
Pennsylvania State University - Plant Pathology Fact Sheets: Provides diagnosis and control measures for common diseases of ornamental plants frequently grown in the northeastern U.S.
Texas University: Description and control of a large range of diseases of crops, turf, ground covers, shrubs, trees and flowers.
University of Arizona: Information and pictures of plant diseases (listed by crop or plant common name), disease publications, newsletter and related links.
University of California, Davis: Information that aids in disease diagnosis of a number of crop plants, proper sampling procedures for submission to diagnostic labs, and the principles of epidemiology and disease management.
University of Florida: Description and control practices of crop, citrus, fruit, ornamental, turf and vegetable diseases commonly occurring in the local region.
University of Idaho: Information on plant diseases affecting local crops including barely, beans, corn, sugar beets, potato and wheat.
University of Illinois: Description and control of some common tree diseases.
Virginia State University: Disease fact sheets listed by type of plant including field crops, vegetables, herbaceous ornamentals, and woody shrubs and trees.