SOIL TESTING AND RX AMENDMENTS

[drtreelove]

Over the years we have had many discussions on this forum regarding soil analysis.  I belive that there is a lot of incomplete and mis-information on the subject. Here is my attempt (with the help of AI - Chat GPT) to explain some of the different approaches and methods of soil testing, chemical farming oriented SLAN, organic farming BCSR and the latest soil biology oriented regen ag methods and materials. 

 

SOIL TEST SYSTEMS

Soil analysis systems play a crucial role in understanding soil health and fertility, aiding in agricultural productivity and landscape management. Here's a comparison of several commonly used systems:

1. SLAN (Sufficiency Level of Available Nutrients):

1. • SLAN focuses on determining the available nutrients in the soil that are crucial for plant growth. It typically measures the levels of key nutrients like nitrogen (N), phosphorus (P), potassium (K), and sometimes other essential elements such as calcium, magnesium, sulfur, etc.
   • The analysis helps in determining if the soil has sufficient levels of nutrients to support optimal plant growth without excesses or deficiencies.

SLAN is the primary method available from most university and commercial soil labs, as well as home NPK soil testing kits. It is chemical ag based and not consistent with ‘organic’ or ‘regenerative ag’ methods and materials.

2. BCSR (Base Cation Saturation Ratio):

2. • BCSR is a soil fertility concept that focuses on the balance between certain positively charged ions, known as base cations, in the soil. These base cations typically include calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na).
   • BCSR aims to maintain an ideal ratio between these base cations, which is believed to support optimal soil structure, pH, nutrient availability, and microbial activity.

This soil analysis method, which is inspired by the work of Dr William Albrecht covers a wider range of plant nutrients than the SLAN method.

3. Haney Test:

3. • The Haney Test is a comprehensive soil health assessment that goes beyond traditional nutrient analysis. It includes measures such as microbial activity, organic matter content, soil respiration, and the potential for nutrient cycling.
   • This test provides insights into the overall biological activity and health of the soil, which can help in making informed decisions regarding soil management practices, including fertilization and crop selection.
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https://www.nrcs.usda.gov/sites/default/files/2022-09/HaneyTest.pdf

 

4.    Soil-Food -Web microbial analysis:

Soil Food Web advocates and regenerative agriculture growers often use a soil testing system called the Soil Food Web Analysis. This method, pioneered by Dr. Elaine Ingham, focuses on assessing the health and biological activity of soil by examining the diversity and abundance of microorganisms such as bacteria, fungi, protozoa, nematodes, and microarthropods.

The Soil Food Web Analysis typically involves collecting soil samples from various depths and locations within a field or garden. These samples are then analyzed using microscopy and other techniques to identify and quantify the different microbial populations present. The goal is to understand the balance and diversity of organisms in the soil, as well as their interactions with each other and with plant roots.

By understanding the soil food web and its dynamics, growers can make informed decisions about soil management practices, such as composting, cover cropping, crop rotation, and reduced tillage, to promote soil health and fertility in a sustainable manner.

 

Comparison:

• Focus: SLAN primarily focuses on the levels of available nutrients, whereas BCSR looks at the balance of specific base cations, and the Haney Test assesses overall soil health, including biological activity. The Soil Food Web analysis is specific for microbiome assessment.
• Depth of Analysis: SLAN typically provides a basic analysis of nutrient levels, while BCSR delves into the balance of base cations, and the Haney Test offers a more holistic view by considering microbial activity, organic matter, etc.
• Application: SLAN and BCSR are often used in conventional agriculture for nutrient management and soil fertility improvement. The Haney Test is gaining popularity, especially in sustainable agriculture and regenerative farming practices, where soil health and biodiversity are prioritized.
• Complexity and Cost: SLAN is relatively straightforward and cost-effective, while BCSR requires more nuanced interpretation and analysis. The Haney Test is the most comprehensive but also the most complex and expensive of the three options.

 

Regenerative Agriculture, as promoted by Kiss the Ground advocates, The Soil Food Web School and Advancing Eco Agriculture, as well as others, represents a modern movement away from pure chemical soil analysis toward a primary consideration of the soil biology and related processes, and how the microbiome is affected positively or negatively by management of growing methods and materials.

 

Don’t miss this key perspective on soil food web and regenerative agriculture:

John Kempf,  Changing Agronomy with Biology

https://www.youtube.com/watch?v=cHPOMBe2SUE