Get the dirt on your soil — at STRAL

STRAL

In an average year, STRAL receives approximately 25,000 samples and runs 75,000 analyses, generating nearly one million individual data points.

‘Regular series’ soil tests from the public account for a fifth of the samples STRAL processes. Here, Soil Lab Manager Cassie List is doing pH testing as part of a ‘regular series’ test.

Texture and organic matter are analyzed as part of a ‘regular series’ soil test. The relative amounts of sand, silt, and clay are estimated by the feel of the soil in a moist condition and then classified into one of five categories: coarse, medium, fine, peat, or muck.

Members of the public can drop soil samples off directly at the lab or mail samples in. The turnaround time for a regular series test is 10-14 days.

The Research Analytical Laboratory offers over 100 different tests on soil, water, feeds, foods, compost, plant or animal tissue, and many other types of materials. Here, STRAL Research Manager Keith Piotrowski prepares samples for the flow injection analyzer.

Angela Gunlogson is the Research Analytical Laboratory’s Plant Lab Manager. Here she is setting up samples from sugar beet leaves to run through the carbon/nitrogen analyzer. Angela calibrates, maintains, and runs the analyzer, and at the end, evaluates the data to make sure quality control indicators are all within expected ranges, making sure there is no indication of instrument or human error somewhere along the way.

Quality is STRAL’s top priority. For every analysis run throughout the lab, technicians calibrate the instruments and check those calibrations against Certified Reference Materials and internal and external standards. As much as 20% of the lab’s testing efforts are dedicated to quality assurance and quality control.

Grab your shovels and send us some soil! As the snow melts and spring begins to make its debut, the University of Minnesota Soil Testing Lab prepares for a surge in soil samples from fields, lawns, and gardens across the Midwest.

The Soil Testing Lab does routine soil fertility testing for farmers, gardeners, landscapers, and municipalities, as well as various soil analyses for university researchers. Its counterpart, the Research Analytical Laboratory, provides a wide range of analyses of soil, plant, water, and other materials in support of university, government, and private company research.

Together, the Soil Testing and Research Analytical Laboratory make STRAL, a unit housed in the Crops Research Building on the St. Paul campus. STRAL Research Manager Keith Piotrowski emphasizes that while the two labs serve two distinct purposes, they operate in an integrated manner.  

“Most of our work for the public runs side-by-side with the work we do for research,” Piotrowski explains. “We apply the same techniques and attention to detail to soil samples from the public as we do for samples that are part of publishable research.”

The Soil Testing Lab focuses on measurements of nutrient status in the soil in order to provide science-based fertilizer recommendations for plant growth and environmental safety. The lab’s ‘regular series’ test - an analysis of phosphorus and potassium, pH levels, and soil texture - gives homeowners, gardeners, landscapers, and farmers a comprehensive look at their soil and makes recommendations on how to amend identified issues.

“Anybody can get their soil tested here - you don’t have to be an expert,” says Piotrowski. “Our reports are easy to read and include links to additional resources to help readers interpret the results and eliminate potential issues with soil fertility or pH.” 

Soil testing is available to the public year round. For more information on soil testing, visit soiltest.cfans.umn.edu/. 

For information on the Research Analytical Laboratory, visit ral.cfans.umn.edu/.