Our Methods

Our Soil Testing Methods

We use a variety of instruments to analyze soil samples including:

  • atomic absorption spectrophotometers;
  • Inductively Coupled Plasma Spectrometers (ICPs);
  • Lachat Flow Injection Analyzer;
  • colorimeters; and
  • general laboratory equipment.

Brief descriptions of our soil testing methods are listed below.


Sample Preparation

At the laboratory, each sample is assigned an identification number, transferred to a paper bag, and then placed in a metal tray. Every 12th sample is a quality control sample, either a check sample of known chemical properties to ensure accuracy, or a duplicate sample to evaluate laboratory precision.

Samples are dried rapidly under forced air, the temperature not exceeding 95oF.

Dried samples are crushed with a mechanical grinder, and passed through a stainless steel 10-mesh 2.0 mm sieve to remove stones and unwanted debris.


Routine Soil Tests (regular tests)


Soil Tests Made Upon Request


Florist/Greenhouse Tests



Recommended Chemical Soil Test Procedures for the North Central Region. 1988. North Central Regional Publication No. 221. NDSU Bull. No. 499.

Soil Testing Procedures

Soil Testing Procedures Graphic