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Frequently Asked Questions

Answers to our new customers’ most common questions


What paperwork do I need to send in with my samples?

Mail-In samples must be submitted by completing the online Submittal Forms, which are available through the Solum online account system.

What is the turnaround time for soil testing?

Customers may opt for a 3-day guaranteed delivery time. These samples will receive priority treatment and will be free of charge if delivered after 3 business days (M-F). Traditional samples will be delivered as quickly as possible but may take up to 5 days. Sample results will be made available in real-time through the online portal.

Is there a place to drop samples at your lab?

We have a drop box located in our parking lot next to the overhead door.

What is the difference between the moist process and the dry process?

Measuring field moist is a better predicator of a crop’s potassium needs and moist measurements are more consistent with time and allow users to better identify long-term trends in a field. Drying and grinding a sample increases the potassium level that is measured and makes it more difficult to predict crop response.

What are the recommendations for my traditional soil analysis results?

Most nutrients, such as P, pH, and O.M. are not changed by the field moist process.  For these nutrients, our main advantage is quality and speed.   The one nutrient that does change significant when soils are dried is potassium.   Iowa State University  offers official recommendations for how to use these results for K.  The fertility classes for this nutrient are summarized in the following table.

Soil Test K Classes Very Low Low Optimal High Very High
Field Moist / Slurry 0-50 ppm 51-86 ppm 86-120 ppm 121-155 ppm 156+ ppm
Crop K Fertilizer Recommendation in lbs. K2O5/acre
Corn 130 90 45 0 0
Soybean 120 90 75 0 0
Corn-Soybean 220 165 120 (60) 0


What tests are available?

The Solum standard analysis includes: P, K, pH, BpH (Sikora), S, Zn, Ca, Mg, Na, OM (LOI), %BSAT, CEC, Regressed Bray, Regressed DTPA Zn, and Regressed NOAc Ca.

Bray/Olsen package involves Bray on all samples and Olsen for sample with pH > 7.35.
Olsen only package delivers Olsen results only for samples with pH >7.35.
Micronutrients include Iron (Fe), Copper (Cu), Boron (B), and Manganese (Mn).




More questions? We have answers.
Call us at 855-GO-SOLUM

About Solum™

Solum’s™ mission is to develop software and measurement technology that makes the business of Agriculture simpler and more productive. Our advanced soil nutrient and fertilizer response models are developed by Solum's™ industry leading soil measurement laboratory in Ames, Iowa.

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615 South Bell Avenue
Ames, IA 50010
(515) 661-5500

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