Precipitated Calcium Carbonate to Remediate Acidic Eastern Idaho Soils

Project Overview

Project Type: Professional + Producer
Funds awarded in 2023: $75,000.00
Projected End Date: 08/31/2026
Grant Recipient: University of Idaho
Region: Western
State: Idaho
Principal Investigator:
Dr. Jared Spackman
University of Idaho
Jared Gibbons
University of Idaho
Justin Hatch
University of Idaho
Tom Jacobsen
University of Idaho
Joseph Sagers
University of Idaho


  • Agronomic: barley, medics/alfalfa, wheat


  • Crop Production: application rate management
  • Education and Training: demonstration
  • Soil Management: soil quality/health

    Proposal abstract:

    Soil acidification negatively impacts the potential yield and quality of agronomic crops, decreases plant available nutrients in the soil, and increases weed and disease pressure. While most arable farmland in eastern Idaho has high pH testing soils, soil acidity is becoming increasingly problematic in eastern Idaho, especially in Fremont, Caribou, Bonneville, and Oneida counties. Precipitated calcium carbonate (PCC, a by-product derived from the sugar beet sugar purification process) is a readily available lime source to remediate acidic soils in eastern Idaho. This project will address the needs of eastern Idaho producers by conducting on-farm, variable PCC rate strip trials and annually monitoring changes in crop yield, weed presence, and soil pH at multiple soil depths over three years. This project will also evaluate the DualEM electrical conductivity sensor to map changes in soil texture across a field and develop variable rate PCC prescriptions. Education and outreach about soil acidity, its impacts on agriculture, liming materials, and how lime rate prescriptions are made will be done through annual field days; outreach materials including newspaper, TV, and radio stories;  presentations at producer and professional meetings; and Extension bulletins and journal articles. We expect this project to benefit 160,000 acres of acidifying soils in eastern Idaho, and to be of value to producers in northern Idaho and other western states. We anticipate this project to have 400 direct contacts and 11,000+ indirect contacts annually.

    Project objectives from proposal:

    • Conduct on-farm field trials to remediate acidic soils using precipitated calcium carbonate in eastern Idaho (September 2023 – August 2026)
    • Provide agricultural stakeholders with information regarding liming for acidic soil remediation and weed control through direct engagement at field days and workshops and indirect contacts including newspaper articles and Extension bulletins (September 2024 – August 2026).
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.