Biological Fertility

 Since 1975 Woods End has offered soil testing emphasizing organic matter and its related soil functions .. a program deposition to advance sustainable soil fertility.

In 1988 Woods End started offering a comprehensive “Soil Quality Audit”, combining  physical, biological and nutrient tests in a single integrated report. This was very likely the first test offering in the USA for what today is popularly called “soil health analysis”.

Soil health is not a fixed, intrinsic soil property but emerges out of interactions. Therefore, laboratory methods must be designed which can represent a range of both quantitative and qualitative factors which are expected to relate to healthy functioning.  The manner in which soils are handled and processed before and during testing also influences the results with a high potential for laboratory artifacts.

To approach a realistic test for soil health  Woods End has designed a process that includes the following:

  • Minimal sample disturbance:  It is common to use powerful grinders to prepare soils before testing, since homogenization is believed to improve soil test reliability, which is does for chemical nutrient tests. However, this form of handling, disrupts bio-physical  features of soil which are highly relevant to soil biological health. Woods End applies measures such as soil-rolling to avoid this;
  • Measuring organo-physical traits: Water stable aggregates are among the most dynamic features of a healthy functioning soil. Woods End has developed a volumetric (“VAST”) method that enables evaluation of erosion-prone vs dispersion-resistant soils;
  • Biological assays:  Modern “science-based” farming has traditionally paid little or no attention to soil biology. To overcome this limitation, assays are needed which are not typically quantitative in the manner that soil chemistry is. Soil respiration – the release of CO2 by microbes – is a backbone test to evaluate biological carbon turnover, a test which the lab has 40 years experience with. The deposition and accumulation of  organic nitrogen in soil forms the basis for a new, special test for labile amino-N;
  • Eco-Physiographic Regions: Given the wide variety of soil types and climatic zones in the world, the use of a single soil health model for any soil  analysis is optimistic but highly unrealistic. To overcome this, Woods End reports are matched regionally to climate, rainfall zone and soil order and sub-orders. This aids in establishing appropriate benchmarks for more accurate interpretations;
  • Keyed Interpretation: Individual soil health indicators are not universally applicable. Wood End’s experimental approach to soil health testing allows up to constantly improve interpretation and to avoid popular generalizations.

The overall approach is represented by the commonly used “triangle” of chemical, physical and biological traits reported as a unified test, the Solvita Soil Health Suite. Woods End is America’s only lab that has consistently since 1988 used this approach. The test compares to other protocols which also emphasize the interaction of these factors.

1- Premium Soil Health Test

  • Evaluates quality and not just quantity of soil organic matter.
  • Accounts for soil microbial biomass via respiration instead of indirect chemical measures;
  • Evaluates nutrient mineralization potential, the core of the nutrient supply mechanism for plants
  • Represents nutrients likely to be “plant relevant” from lighter-weight extractants

2- Basic Soil Health

  • Our basic soil health test is meant to be a companion to common soil nutrient analyses obtained elsewhere or through your favorite soil lab. The basic adds information about biological and bio-physical traits that are not available elsewhere.  Included is Solvita CO2, SLAN, Water Stable Aggregates, Water soluble carbon (WSOC), Soil C:N ratio, and Respiratory Quotient.

Eco-Physiography: reports include matching US soil samples to eco-physiography, climate/rainfall zone as well as to major soil order and sub-orders.  See Sample Info Form for pricing.

What you get:

  • A comprehensive report with a Fertility Score and a Soil Health Score. The standardized Score uses an open source formula with equal weighting of 5 attributes associated with high functioning soils. The fertility score shows the expected nutrient supply (based on expected crops) integrated with the soil health score.
  • Interpretation Guide: Each customer receives a full interpretation guideline with the report.

Please provide the following:

  1. The soil sample: (wet or dry) in a quart sized ziplock bag, with the date of the sample and the intended crops.  If the location is different than the zip code on the order, please provide specific GPS or sample zip code information which we use to map to your climate zone.
  2. Sample Information Form: Please attach the following Sample-information with each order.

**Mail to our PO BOX if sending via USPS, or our street address if sending via UPS or FEDEX**