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NOTE: Due to the ongoing situation with COVID-19 the Cornell Soil Health Laboratory is temporarily closed. We ask that our clients please refrain from sending samples to our lab at this time. If you have already collected soil samples please store the samples at refrigerator temperature and send them to our lab when we reopen. We expect to reopen in the coming weeks and will post a notice on our website and social media accounts when we are able to reopen. Any samples currently en route to our lab will be refrigerated upon receipt. It is highly likely that our ability to report results from analyses in process will be delayed. Thank you for your patience during this time and please stay happy and healthy. Please send questions to

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The Cornell Soil Health Testing Laboratory is the home of the Comprehensive Assessment of Soil Health (CASH):

The Comprehensive Assessment of Soil Health is designed for farmers, gardeners, agricultural service providers, landscape managers and researchers who want to go beyond simply testing the nutrient levels of their soils. It was the first commercially-available laboratory soil health test that provided standardized information on important soil biological and physical constraints, in addition to standard nutrient analysis.

The Assessment is regarded as a key tool for soil health measurement by several national initiatives, including The Soil Health Institute,  the Soil Health Partnership, and the USDA-NRCS Soil Health Division. We have conducted over 10,000 soil health package analyses since its rollout in 2006. Half were for commercial customers. In addition to the laboratory results for each sample, we have developed a soil health management planning framework included with the sample assessment results to help you focus management changes where they will be most effective in improving your soil.

The assessment’s indicators and management strategies for improving soil health are also detailed in the Comprehensive Assessment of Soil Health Training Manual, available free online.

Important information regarding changes to shipping and packaging protocols:

Beginning June 1st 2016 each individual sample needs to be double bagged prior to packaging and shipping. Packing material such as crumpled paper or bubble wrap must be placed in the box with the samples to prevent sample movement and spillage during shipping. For more details on proper packaging and shipping instructions, please visit the ‘Testing Services’ tab on our website.

There are certain counties in the US where soil should neither be packaged nor shipped. Soil received from these counties will be destroyed without processing. For a complete list of prohibited counties please visit the ‘Resources’ tab on our website.

Corrected Percent Soil Organic Matter (%OM) Reporting 7-8-19

Cornell Soil Health Lab Clients,
We experienced an unfortunate error in the percent organic matter (%OM) data delivered in a subset of soil health reports beginning March 2018. At that time, the Cornell Soil Health Laboratory began outsourcing the nutrient analysis portion of the Soil Health test, including OM analysis, to another lab entity. This resulted in a data transfer error that has now been identified.
What was the problem? The %OM estimate from the partner lab was based on the same Loss on Ignition (LOI) methodology used previous to March 2018. We recently discovered that the %OM data that we received – and was reported to you – had an inadvertent data processing issue that unbeknownst to us applied a secondary conversion equation to the OM results. This resulted in overestimated %OM values, typically by about 0.4 to 0.6%. If you are interested, specific details relating to the mechanics of the error are described below.
What is the impact to you? The magnitude of this error is modest when considering a single soil health analysis. The concern is greatest for projects that collected samples before March 2018 and want to discern trends through a follow-up sample analyses conducted after March 2018. In such cases the OM increase will be artificially high and should be corrected.
What are the corrected OM values? Corrected data is being sent to replace the corrupted values along with the corrected %OM data and associated scoring. We simply applied the inverse of the secondary conversion equation to the %OM data that we received.
We sincerely apologize for this inconvenience and that it took considerable time to find the source of the problem. The issue only became apparent when some clients compared recent OM test results with those from pre-March 2018 and noticed unexpected large increases. We had verified that our partner lab used the same quality control procedures as the Cornell Lab and we confirmed that the OM data sent to us met the QC standards. The partner lab therefore followed good laboratory procedures, but the error entered in the data processing phase. This has now been corrected.
Deeper explanation of the source and solution of the problem: The methodology for obtaining % Organic Matter is described in our Fact Sheet 16-08 Soil Organic Matter. This methodology was followed but a secondary conversion equation was inadvertently applied to the data before it was sent to us. The following equation has been used to correct the data back to the true %OM values:
%OMcorrected = (%OM – 0.2651) / 1.0688
We are now again running the Modified Morgan extraction of chemical nutrients, the 2:1 water pH and %OM in-house at the Cornell Lab. All data coming from the Cornell Lab after July 1, 2019 will be verified with our Quality Control protocols. This control of the data will ensure that this type of error cannot occur again.

NOTE: Only soil health samples in the range RR1040-RR2415 and SS1-SS1505 are affected with the issue described above. Corrected data has been or is being sent to replace the corrupted values. Please contact or Bob Schindelbeck at for more information.

Cornell Soil Health Program featured in USDA video

Soil painting celebrates 2017 World Soil Day

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