Agronomy

Manual published in 2011 by the National Resources Conservation Service of the U.S. Department of Agriculture.

The Soil and Plant Testing Laboratory analyzes soil, plant, water, manure, compost and greenhouse media. The laboratory provides quality testing and unbiased, research-based recommendations to clients for economically viable and environmentally safe nutrient management practices.

Includes the Plant Available Nitrogen calculator and the CAFO Operator Curriculum, as well as manure applicators.

NRCS delivers science-based soil information to help farmers, ranchers, foresters, and other land managers effectively manage, conserve, and appraise soil.

Michigan State University's Turfgrass Information Center houses the most comprehensive publicly-available collection of turfgrass research and educational materials in the world. It maintains the Turfgrass Information File (TGIF), a database providing access to 250,000+ materials reporting on aspects of turfgrass and its maintenance.

Global Plants is the world’s largest database of digitized plant specimens and a locus for international scientific research and collaboration.

Crop Explorer is a tool managed by the Foreign Agricultural Service's International Production Assessment Division. View crop production data from around the globe, as well as crop calendars, market and trade information, and more.

​Grow is an outreach service of The American Phytopathological Society. It is a nonprofit, freely available resource of science-based information on plant health.

Maintained by the USDA, the PLANTS Database provides standardized information about the vascular plants, mosses, liverworts, hornworts, and lichens of the U.S. and its territories.

Organic Eprints is an international open access archive for papers and projects related to research in organic food and farming. The archive contains full-text papers in electronic form together with bibliographic information, abstracts and other metadata. It also offers information on organizations, projects and facilities in the context of organic farming research.