How the IR-4 Project Can Help Your Greenhouse Grow
May 18, 2026 If you’ve ever struggled to find a labeled product for a pest issue in your crop, the IR-4 Project is likely part of the reason new options eventually become available. The IR-4 Project was established in 1963 to address the “Minor Use Problem,” which is the limited availability of pesticide registrations for specialty crops such as vegetables, fruits, herbs, and ornamentals. Because of the cost and complexity of registration, many products are developed primarily for large-acreage agronomic crops, leaving specialty crop growers with fewer tools.
IR-4 helps address this gap through a coordinated effort involving USDA, university research programs, EPA, industry partners, and growers. The program generates the data needed to support pesticide registrations — including conventional, organic, and biological products — helping ensure growers have access to effective pest management tools across a wide range of crops and regions.
The process begins with growers, Extension specialists, and industry representatives identifying unmet pest management needs. These priorities are evaluated and supported through coordinated field trials across multiple regions. IR-4 then compiles the data and works with regulatory agencies and manufacturers to secure new or expanded registrations.
How Growers Can Use IR-4
While IR-4 operates at a national level, grower input plays a direct role in shaping which tools become available. Communicate directly with Extension specialists and advisors about critical, unmet pest management needs. You can also contact your state’s IR-4 liaison to discuss pressing issues and help elevate priority concerns. You can also work through commodity groups or grower organizations to submit Project Clearance Requests, which formally nominate high-priority needs for IR-4 consideration.
Where IR-4 Makes the Biggest Difference
IR-4’s influence is often most visible in areas where pest pressures are high, but labeled options are limited. For example, IR-4-supported research led to EPA approval of expanded uses for glufosinate-ammonium in 2022 and 2023, making this herbicide available across a wide range of specialty crops, including vegetables, melons, and hops. These label expansions provide growers with an effective tool for weed control, helping to diversify management programs.
The impact of IR-4 is substantial. A 2022 Michigan State University report estimates the program contributes approximately $8.97 billion annually to U.S. GDP, with federal funding generating a $525 return for every $1 invested.
In March, Dr. Lina Quesada-Ocampo, a vegetable pathologist and Extension specialist at North Carolina State University, became the new executive director of the IR-4 Project. She brings more than 15 years of experience in applied pest management research and Extension, with a focus on supporting specialty crop growers. In her new role, she aims to strengthen collaboration, improve regulatory efficiency, and ensure growers have timely access to safe and effective pest management tools.
In short, the IR-4 Project plays a critical role in ensuring specialty crop growers have access to the tools they need to manage pests effectively. As new challenges emerge, continued engagement from growers and industry will be key to keeping that pipeline moving.
This piece was originally featured on our sister site, Growing Produce. For more information on the IR-4 Project, including a step-by-step look at what it takes to get a new use approved, click here to read the original article.
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