TN_450_3 - TN 450-TCH-3 Recommended Soil Health Indicators and Associated Laboratory Procedures
TN 450-TCH-3 Recommended Soil Health Indicators and Associated Laboratory Procedures
Technical Notes: 450-TCH-3 Date: June 5, 2019
Subject: Recommended Soil Health Indicators and Associated Laboratory Procedures

Purpose.  To announce the release of the Technical Note, 450-03, Recommended Soil Health Indicators and Associated Laboratory Procedures. This technical note contains a minimum data-set of recommended current best available standard laboratory methods for soil health indicators selected through a collaborative multi-organizational effort, as described in the document.   
Expiration Date. Effective upon receipt.
Background.  USDA/NRCS and partner efforts to assess soil health problems and impacts of management nationally, as part of conservation planning and soil health management systems implementation, will be facilitated by measurement of soil health indicators using a standard set of methods.          
Explanation. Soil health is defined as the capacity of the soil to function as a vital living ecosystem to sustain plants, animals, and humans.  Six key soil physical and biological processes were identified that must function well in a healthy soil, and therefore would especially benefit from measurement methods standardization: 1) organic matter dynamics and carbon sequestration, 2) soil structural stability, 3) general microbial activity, 4) C food source, 5) bioavailable N, and 6) microbial community diversity.  The chosen methods largely met key important criteria including indicator effectiveness with respect to management sensitivity and process interpretability, ease of use, cost effectiveness, measurement repeatability, and ability to be used for agricultural management decisions. 

The use of these methods and development of a national dataset that allows for their soil- and climate-based interpretation can provide a standard starting point against which other or new methods can be compared.  The technical note outlines the methods used to monitor the Soil Health Demonstration Trials as part of the new On-Farm Conservation Innovation Trials and will provide the foundation for the use of standardized soil health assessments for use in conservation planning and monitoring.

Distribution.  This directive is available on the NRCS Electronic Directives System Web site at

Filing Instructions.  The availability of this information is limited to electronic format. If a paper copy is retained, file it sequentially within Title 450, Technology, of the Technical Note binder.

Contact. For more information, contact Bianca Moebius-Clune, Director, Soil Health Division, by telephone at (202) 763-9205 or by email at    



Deputy Chief for Science and Technology               

Attachment - Recommended Soil Health Indicators and Associated Laboratory Procedures - Jan. 23, 2020
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