Reference strips and precision sensors for increased nitrogen use efficiency in wheat production

Project Overview

Project Type: Professional + Producer
Funds awarded in 2013: $49,907.00
Projected End Date: 12/31/2015
Region: Western
State: Montana
Principal Investigator:
Dr. Olga Walsh
Montana State University


  • Agronomic: wheat


  • Crop Production: foliar feeding, no-till, nutrient cycling, application rate management, tissue analysis
  • Education and Training: demonstration, extension, farmer to farmer, mentoring, on-farm/ranch research, participatory research, workshop, youth education
  • Energy: energy conservation/efficiency
  • Farm Business Management: agricultural finance
  • Soil Management: soil analysis, nutrient mineralization, soil quality/health
  • Sustainable Communities: sustainability measures


    While nitrogen is a key nutrient limiting wheat grain production, its use efficiency is only about 30%. As nitrogen is lost via volatilization and plant loss, run off and leaching, immobilization and denitrification, about 70% of funds wheat growers invest annually in nitrogen fertilizer is being lost as well. Non-limiting nitrogen reference strips in combination with precision sensors such as GreenSeeker® (Trimble Navigation Ltd., Sunnyvale, CA) has been successfully used throughout the Midwest and elsewhere to accurately estimate crop yield potential and the crop’s prospective responsiveness to nitrogen mid-season. This methodology enables producers to generate topdress fertilizer recommendations based on crop’s precise requirement for nitrogen. This system helps to significantly increase nitrogen use efficiency and has been shown to net wheat growers more than $25 per acre in fertilizer savings. Researchers at Montana State University are aiming to develop algorithms for Montana wheat varieties and growing conditions within two to three years. This project was focused on ensuring that wheat growers are prepared to successfully utilize the algorithms and are equipped with knowledge and expertise to fully benefit from sensor-based technologies.


    Our project is focused on educating and training wheat producers on how sensor-based technologies can increase the efficiency and profitability of their farm operations. Precision sensors enable to develop crop-specific and site-specific yield potential-based topdress nitrogen recommendations and to increase nitrogen use efficiency. Sensor-based nitrogen management strategies directly results in:

    i. satisfaction of human food needs (due to efficient and sustainable production of wheat - principle food grain produced in the United States)
    ii. improving the environmental quality (fertilizer is applied strictly based on crops need for nitrogen, which optimizes nitrogen uptake and minimizes nitrogen loss to the environment; non-source pollution associated with intensive crop production is reduced)
    ii. making the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls (enables to account for spatial and temporal nutrient variability present in agricultural fields and optimizes the use of non-renewable resources such as soil nutrients, and on-farm resources such as fuel, time, and labor)
    iv. sustaining economic viability of farm operations (increased efficiency of grain producing operations - significantly minimized annual losses to producers due to improved nutrient management strategies)
    v. enhancing the quality of life for farmers and society as a whole (due to making farming operations more efficient and providing substantial savings in fertilizer inputs, fuel and labor, as well as improved environmental quality; agricultural education and outreach components of the project will significantly increase growers' ability to make more informed nutrient management decisions; feeling in control of their financial investments in fertilizers will ensure the improved quality of life for growers, their families and their communities as a whole).

    • Wheat production covers over 5,000,000 acres of agricultural land, employs approximately 15,000 individuals, and accounts for approximately 25% of Montana’s total agricultural revenue.
    • Rural farming communities have greatly benefited from this project through enhanced knowledge of precision agriculture techniques and improved decision-making skills for more profitable farm operations management. With 787, 472, 836, 520, 700, 405, 1037, and 297 individual farm operations in Chouteau, Glacier, Hill, Pondera, Teton, Toole, Cascade, and Liberty counties, respectively, we have reach over 5,000 crop producers within Golden Triangle – Montana’s key grain growing area. A precision nutrient management blog has ensured that project's milestones and successes are effectively communicated to a much broader grower audience in Montana, other regions of the United States, and elsewhere.
    • The agricultural sector is experiencing lack of excellent agricultural specialists trained to employ cutting edge technologies and to have the expertise to successfully work with growers. We have trained a graduate student in sensor-based nutrient management and in conducting of on-farm research studies.

    Project objectives:

    This project’s objectives and expected outcomes are directly related to the definition of sustainable agriculture as defined by the U.S. Code Title 7, Section 3103 of the U.S. Congress.

    1. To establish on-farm studies to demonstrate that non-limiting nitrogen reference strips - in combination with precision sensing methodologies – can be effectively used to accurately determine wheat demand for nitrogen.
    2. To educate and train wheat growers on how sensor-based technologies can increase the efficiency and profitability of their wheat production operations.
    3. To train graduate research assistants to utilize sensor-based technologies and to conduct on-farm research.

    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.