Long-Term Soil Test Monitoring in Minnesota Cropping Systems


Start Date: 2012

Principal Investigator: Daniel Kaiser

Organization: University of Minnesota, Department of Soil, Water and Climate

Status: Ongoing

Background Information:

Soil tests are used to monitor the potential responsiveness of crops to fertilizer. When fertilizer is under applied there is a risk for a decrease in soil test levels. As crop yields increase the removal of nutrients increase. Even if fertilizer is applied to replace the nutrients lost, some crop consultants still notice decreases in soil test levels. It is unclear if some of this decrease is due to changes in where a sample was taken or due to under-application itself.


To improve sampling accuracy, GPS receivers can be used to mark point within fields to allow for returning back to the same spot. Monitoring soil test values at a single location over the growing season could aid in identifying problem spots when soil test levels decrease at unexpected rates. Through partnerships with crop consultants and dealers, this study monitored soil test levels at single point in a field. Throughout the growing season, soils were sampled from producer fields fertilized according to standard practices in order to gauge change in soil test levels.

 Key Findings:

Results not yet published.


©2019 Agricultural Fertilizer Research and Education Council of Minnesota