Effects of Subsurface Micro-irrigation on Water Use Efficiency and Hazelnut Tree Growth

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2019: $19,767.00
Projected End Date: 06/30/2022
Host Institution Award ID: G237-19-W7501
Grant Recipient: ZD Farms of Oregon
Region: Western
State: Oregon
Principal Investigator:
Darrel Smith
ZD Farms of Oregon


  • Nuts: hazelnuts


  • Crop Production: application rate management, drought tolerance, fertigation, irrigation, water management
  • Education and Training: demonstration, extension, farmer to farmer, on-farm/ranch research
  • Energy: energy conservation/efficiency
  • Farm Business Management: whole farm planning

    Proposal summary:

    Effects of Subsurface Micro-irrigation on Water Use Efficiency and Hazelnut Tree Growth

    Moisture losses associated with surface evaporation and weed growth under conventional surface irrigation methods, support research of highly efficient irrigation methods for producers to better conserve water and increase production efficiency. Drip irrigation is the most efficient method of irrigation but also has issues when used in orchards; tripping on the exposed lines, damage to the system from exposure to sunlight and rodents, concerns regarding the effectiveness of delivery of water and nutrients to the roots, and issues with plugged or non-flowing emitters that go undetected.  Subsurface Drip Irrigation (SDI) puts the emitters underground eliminating issues with surface drip systems and micro-emitters. Benefits of SDI include the highest water use efficiency of any irrigation method reducing water use up to 40% while increasing yields and quality.

    This project has three objectives: 1) determine the value of subsurface micro-irrigation on hazelnut tree growth; 2) define the best and most effective use of available irrigation systems for orchard crops; and, 3) evaluate the costs associated and best practices for greatest efficiency in water use for hazelnut growers. 

    This study, an extension of a previously funded SARE project, will clarify the advantages of this new irrigation method for growers coping with water scarcity in the western U.S., and gain a better understanding of growth capacities of hazelnut trees under water stress. The project will take place on a 13.4-acre hazelnut growing operation in the northern Willamette Valley of Oregon where 1,100 hazelnut trees have been planted in the last 4-years.

    Education and outreach will include field days (pre- and post-harvest), irrigation in orchards “How-To” guide that will be distributed for free to orchardists in the region, articles in trade publications, and sharing the research results via social media outlets.

    Project objectives from proposal:

    Overall goal: Achieve comprehensive understanding of subsurface micro-irrigation on hazelnut tree growth and hazelnut quality using minimal amounts of water to achieve acceptable nut quality.

    Obj 1: Evaluate efficiency of our subsurface micro-irrigation strategy on water conservation

    • Sub-obj 1: Calculate water saved without diminishing nut quality [Oct. – Dec. 2019/2021]
    • Sub-obj 2: Compare different water use efficiency between subsurface micro-irrigation methods and surface drip irrigation [Oct – Dec. 2019/2021]
    • Sub-obj 3: Determine combinations of water delivery amount and irrigation depth yielding highest water use efficiency [Oct – Nov. 2019/2021]


    Obj 2: Measure the impact of our new subsurface micro-irrigation strategy on hazelnut growth and nut quality

    • Sub-obj 1: Assess role of subsurface micro-irrigation strategies in hazelnuts quality [Mar.– Nov. 2019/2021]
    • Sub-obj 2: Quantify subsurface micro-irrigation effects on hazelnut root distribution [Apr. – Nov. 2019/2021]
    • Sub-obj 3: Analyze nutrient content in hazelnuts [Oct. – Mar. 2019/2021]


    Obj 3: Educate hazelnut producers and engage community members on irrigation water conservation and hazelnut quality improvement

    1. Sub-obj 1: Conduct workshops to educate producers about improving hazelnut quality by using less irrigation water [Feb. & Aug. 2019/2021]
    • Sub-obj 2: Develop educational materials for orchard managers and hazelnut growers to conserve irrigation water and improve water use efficiency [Jan. 2019 – Apr. 2021]
    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.