Our influences and learning resources

Where this project began

Godai Furuta created the original mineral balancing spreadsheet and formulas that this project is based on. Godai and Jarrod Scully met as fellow students of Scott and Sara Skamnes through the Crescive Forum and Crescive Growers Group and became friends. Living Soil Supplies is building on Godai’s work to make soil-test entry, calculations and comparisons easier to use.

Dr. Elaine Ingham and the Soil Food Web School

Dr. Elaine Ruth Ingham lived from June 26, 1952 to February 16, 2026. Her research and teaching helped establish the biological foundation behind this project.

Life dates and obituary · The school’s tribute

Continue learning through the Soil Food Web School. Its online Foundation Courses cover soil biology, compost production, extracts and teas, and microscopy.

• Course overview
• Foundation Courses
• Introductory mini course
• Advanced practical training

How we use these sources

Scott and Sara Skamnes are the main practical authorities for this project. The Ideal Soil, William Albrecht's work and Marschner's mineral nutrition books are foundational references. Neal Kinsey's teaching provides supporting guidance on mineral balancing and soil chemistry.

When sources differ, we show the difference and the relevant soil, test method and growing context. We keep the selected project rules in place until a change is chosen. References inform the reasoning, and their calculations and units still need to be checked.

The available 2014 v2.0 edition of The Ideal Soil has been reviewed in full, across all 170 PDF pages. Other book reviews cover selected passages, excerpts and edition information. A source listing does not imply a complete review of every edition or independent validation of its claims.

• The Ideal Soil, publisher listing
• The Albrecht Papers, publisher collection
• Marschner's Mineral Nutrition of Plants, publisher listing
• Neal Kinsey, Hands-On Agronomy

Why we recommend their classes

At Living Soil Supplies, we believe Scott and Sara's classes are worth every penny. The teaching, ongoing learning opportunities, forum access, and Mighty Networks community are a big part of why we recommend them.

Crescive describes its Advanced Training masterclass as a lifetime membership, with opportunities to return to classes and Q&A, plus lifetime access to the student and Crescive Growers Group forums. Membership and renewal terms vary by class, so check the details when enrolling.

Masterclasses

Bundles

Workshops and mentorship

How this guides our work

These are guiding principles for this project. The current tools provide a worked comparison and container planning while the full calculator is developed.

How we check the calculations and claims

We check conversion arithmetic against laboratory documents, standard chemical data and independent research. We keep lab-reported results separate from calculated additions and predictions.

Scott and Sara Skamnes remain our main practical references. The selected Crescive profiles are attributed practice targets. Research that differs from an ideal-ratio claim stays visible, including its crop and soil context.

M3 measures extractable nutrients. Saturated paste measures the prepared extract. Neither establishes the amount a plant will take up, and a passed application-cap check does not guarantee plant safety.

This review covered TEC, units, soil mass, fertilizer reporting forms, key test interpretations and biological claims. Product verification and validation of the exact target profiles remain incomplete.

The October 11 follow-up still leaves the exact TEC formula boundaries unresolved. Calcium and sulfur studies support specific plant-metabolism findings, but do not establish that a calcium-plus-sulfur amendment prevents spider mites. The full Ideal Soil reading and added video reviews did not change the selected targets or application caps.

• Logan calculations and conversions
• Independent CEC comparison
• Six-year field study of cation ratios
• Calcium and sulfur in arsenic-stressed mustard seedlings
• Sulfur-containing products in orchard mite bioassays

Choosing mineral tests

The Crescive testing guidance from Scott and Sara Skamnes distinguishes M3 with nitrogen from a fuller panel that adds saturated paste and trace elements. M3 measures extractable nutrients. Saturated paste measures nutrients dissolved under the reported preparation conditions.

For Living Soil Supplies, the requested panel is Logan Labs' Complete Soil Package with Extras, with explicit requests for measured bulk density, organic matter as an exact percentage including results above 20%, and mineral results in ppm. Confirm the requested measurements, since Crescive's course package names differ from Logan's public names.

Following Scott and Sara's Crescive guidance, supply the irrigation or feed-mixing source water for the requested saturated-paste preparation and identify the matching soil samples. Keep the water type actually reported by the lab with each result. A separate water analysis is a separate request.

Logan Labs testing services · Crescive Complete analysis · How nutrient extraction works

Choosing a water test

The Crescive guidance from Scott and Sara Skamnes recommends starting with Wallace Laboratories for commercial cultivation, including international samples, to keep the testing approach consistent. It identifies Logan Labs' Water Suitability Test as an option for noncommercial growers or cases that need a simpler panel.

Choose a panel for the information you need and keep the laboratory, sampling date, water source, treatment and reported units with the results. A separate water analysis and the water used to prepare a saturated-paste test serve different purposes, even when they come from the same source.

Wallace's 2026 form requests at least 10 ounces in a durable, leak-proof container. Logan requests 12 to 16 ounces and recommends taping the bottle lid. Choose a bottle and fill level that meet the receiving lab's requirements, and check its current instructions and price when ordering.

Wallace water sampling form · Wallace testing panels · Logan sampling instructions · Logan testing services

Soil type and amendment analysis

The Crescive guidance from Scott and Sara Skamnes confirms that the AG targets and guidelines refer to field production in native soil. Higher-density soil contains more mass in the same volume, so the same nutrient amount per volume gives a lower ppm concentration. Higher potting-soil targets remain an optional comparison, not an automatic goal for native soil.

Scott and Sara's Crescive guidance describes native-field sulfur readings around 10, 15 or 18 ppm as common and advises reasonable, affordable additions. The native reference table still lists 100 ppm. Keep that reference visible, while reviewing practical rates and sulfur from all amendments before proposing an addition.

Scott and Sara's Crescive guidance uses 20% elemental magnesium as a working assumption for olivine and identifies the older 46% figure as MgO. These are different bases: 46% MgO converts to about 27.7% elemental magnesium. The 20% figure is recorded as a working assumption in their Crescive guidance, separately from a manufacturer analysis and from estimates of nutrient release.

Scott and Sara at Crescive Soil · NIST magnesium oxide composition

Additional learning from Neal Kinsey and Kinsey Agricultural Services

Prioritizing Nutrients. The reviewed discussions add context about reliable tests, crop needs, budget, amendment quality and timing.

Scott and Sara's selected Crescive framework remains the starting point. Kinsey's field experience is a supporting perspective. Individual talks and classes remain credited to the person teaching them.

• Crop and yield context, 10:45
• Soil testing discussion, Kyle and Neal
• Soil composition lesson, Kyle Long
• Sampling lesson, Kyle Long
• Soil fertility webinar, Neal Kinsey
• Albrecht interview, Neal Kinsey
• Soil fertility interview, Neal Kinsey
• Soil-Con 2025, Neal Kinsey Afternoon Session, Building a Healthy Farm Soil
• Neal Kinsey on Soil Fertility for Corn, Wheat and Soybeans
• Bray and Olsen method descriptions, University of Minnesota
• Soil test interpretation, Oregon State University
• Kinsey Agricultural Services podcast directory

Laboratory methods, field-soil context and sampling instructions remain attached to the source. Bray extraction is different from a water-only test. Spoken gypsum limits, copper examples and nutrient-release estimates are not universal rules, and they do not change the calculator's selected targets or caps.

9 of ten videos in this bounded source set have full available-caption reviews, including two lessons taught by Kyle Long. One video still returned no transcript on October 11, 2026. All eight newly recovered transcripts have been reviewed. The corn, wheat and soybean transcript ends mid-answer. Automatic captions and speaker turns have not been checked against the audio.

Sources and further learning

• About Scott and Sara
• Crescive lab analysis
• Mineral test instructions
• Bioassay collection instructions
• Crescive consulting
• The Crescive Method on YouTube
• Soil Food Web School and Dr. Elaine Ingham

Use the instructions for the test you are taking. Mineral tests and biological assessments have different collection and handling requirements.