Editor's notes
The following abstract describes a publication that is only available as a downloadable PDF.
This publication is a revision of North Central Regional Research Publication No. 221 (NCR221).

For more than a century, soil and plant scientists have been developing methods for determining the levels of plant-available nutrients in soils.

Over the past 30 years, the NCR-13 Soil Testing and Plant Analysis committee members have worked hard at standardizing the procedures of soil testing laboratories with which they are associated. As a result of these activities, the committee arrived at the recommended procedures for soil tests.


  • Soil sample preparation
  • Standard soil scoop
  • Soil extraction
  • pH
  • Lime requirements
  • Nitrate-nitrogen
  • Phosphorus
  • Potassium
  • Cations
  • Sulfate-sulfur
  • Micronutrients
  • Zinc
  • Iron
  • Manganese
  • Copper
  • Boron
  • Chlorides
  • Soil organic matter
  • Soil salinity
  • Greenhouse root media
  • Laboratory quality assurance program


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Publication No. SB1001