Nitrogen Mineralization in High-Elevation Hay Meadow Soils for Improved Fertility Management

Project Overview

Project Type: Graduate Student
Funds awarded in 2022: $29,921.00
Projected End Date: 12/31/2024
Host Institution Award ID: G209-23-W9212
Grant Recipient: University of Wyoming
Region: Western
State: Wyoming
Graduate Student:
Principal Investigator:
Urszula Norton
University of Wyoming


  • Agronomic: grass (misc. perennial), hay


  • Animal Production: feed/forage, rangeland/pasture management
  • Crop Production: fertilizers, nutrient cycling, nutrient management
  • Education and Training: extension, farmer to farmer, on-farm/ranch research
  • Soil Management: organic matter, soil analysis, soil chemistry, soil microbiology, soil quality/health

    Proposal abstract:

    Problem: High-elevation hay meadows are a critical but under-performing component of livestock operations in the Mountain West. Flood irrigation, high elevation, and cool temperatures result in concentration of organic materials near the soil surface, constraining N cycling and forage productivity. Limited forage productivity in meadows is surprising considering meadow soils contain as much as 2400 kg N/ha in  the top 10 cm, reflecting a disconnect in the microbial community's ability to mineralize N for plant growth.

    Question: How can the resource of stored N in meadow soils be utilized to reduce dependence on N-fertilizer and improve economic and environmental sustainability of western ranches?

    Solution: Understanding N mineralization in meadow soils will give ranchers tools to better manage natural N-release and reduce N-fertilizer rates.

    Method: We propose an on-farm research trial where soil cores are incubated in-situ and routinely sampled for mineralized N content in order to determine the temporal patterns and magnitude of N release in meadows.

    Outreach: Results will be disseminated to stakeholders through producer meetings and publications in extension and peer reviewed articles. We will also focus on training a core group of ranchers to communicate findings within their communities and promote innovation.

    Expected outcomes: We expect to find N mineralization in meadows occurs in discrete time periods between flooding events when soil conditions are ideal for N mineralization. This knowledge will give our rancher collaborators tools to innovate novel management strategies to optimize N mineralization and fertility management on their operations.

    Project objectives from proposal:

    Research objective 1: Determine the amount of N mineralized in high-elevation hay meadows annually to better predict N availability and reduce dependence on N fertilizer.

    Research objective 2: Determine the temporal patterns of N mineralization so meadow management tactics can target critical periods of N mineralization to optimize N cycling in the field.

    Research objective 3: Determine relationships between N mineralization and soil health indicators to develop measures for evaluating meadow soils with healthy N cycling.

    Education objective 1: Hold producer meetings at three critical stages of the project to relay research findings and updates to local ranchers and stakeholders.

    Education objective 2: Develop a core group of 5-10 ranchers who receive regular communication about our research to foster outreach from within local ranching communities.

    Education objective 3: Disseminate research findings to producers, industry stakeholders, and academia through written and oral media.

    Education objective 4: Hold a producer round-table to develop practical management tactics that implement our research findings.


    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.