Woods End Laboratories

Healthy Soil

Healthy Science

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Owing to the variability of source ingredients that go into it, and the process itself, completed composts require diverse lab testing  before proper use in agriculture and horticulture.

WHAT IS IT? Compost is not a single product nor is it a specific chemical composition. It results from a composting process which itself is not  predetermined or fixed in any way.  Rather, compost as a product may be best defined as organic matter in a late stage of decay.  The original ingredients should not be easily distinguishable visually in the final product, yet the composition when tested will reflect all the input organic and mineral compounds.

LABORATORY PERSPECTIVE: Woods End is America’s oldest-running compost analytical lab which has devoted considerable effort to “deciphering the code” of the process and the product. While very complex, composting reflects a simple natural process. Woods End offers a unique arrangement of tests that indicate the dynamic  process and quality of the end product.

POPULAR, BUT MISUNDERSTOOD: While very popular, compost is often misrepresented both by lay-persons and scientists.  “Is it a soil amendment or a fertilizer”. The unfortunate result of ambiguity and soft-science is that compost is poorly appreciated as a growing media, a fact reflected in its weak showing in professional markets. Within certified organic farming, special attention is accorded to compost which may be the primary nutrient input aside from manures.

Woods End divides the the testing of composting and compost into three categories:

  • Source materialsPre-composting”. Tests to characterize ingredients.
  • Composting  Process - Active State“:  Tests to manage quality during the process.
  • End product – “Completed State” - Tests to evaluate the end-product, such as nutrient value, stability, herbicide contamination.

For an Overview of Available Analyses, go to the HOME page and click on Downloads. NOTE: lab tests have changed significantly in advance of the 2014 season.

To Evaluate What you Need: Please contact us (or call 207 293 2457) for a no-obligation discussion of your testing needs.

Laboratory Certificates and Approvals

Woods End maintains appropriate laboratory inspections, approvals and certifications, principally related to soils and manures. The laboratory is USDA-APHIS inspected (we do not accept foreign compost or manures).  Woods End is OMRI recognized for organic amendment testing (final approval is an OMRI process). Other lab certifications and approvals are: ALP (Agricultural Laboratory Proficiency) for soil testing. For biodegradability in compost we are BPI approved for compostability* (please check status for 2014). We maintain MAP Manure Analysis Proficiency certification. For the previous decade the lab has been enrolled in the  CAP (Compost Analysis Proficiency) program under Dr. Miller but does not recognize the private US Compost Council as a legitimate or qualified approval agency.

Are You Satisfied with your compost product?
Woods End will help you find the right one – or create it.


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