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U.S. National Organic Program Standards: Implications for Researchers

Rosalie L. Koenig
Owner, Rosie’s Organic Farm, Gainesville, FL;
Member, National Organic Standards Board;
Courtesy Assistant Professor, Department of Plant Pathology
University of Florida; Co-director, Center for Organic Agriculture, University of Florida.

Brian Baker
Research Director, Organic Materials Review Institute,
Eugene, OR

Koenig, R.L. and Baker, B. 2002. U. S. National Organic Program Standards: Implications for Researchers. APSnet Features. Online. doi: 10.1094/APSnetFeature-2002-1102


The term ‘organic agriculture’ signifies many different farming practices and philosophies that focus on sustainable farming systems employing ecologically sound agricultural practices. The National Organic Standards Board (NOSB) of the United States Department of Agriculture (USDA) defined organic agriculture as “an ecological production management system that promotes and enhances biodiversity, biological cycles, and soil biological activity” (23). This system is based on minimal use of off-farm inputs and management practices that restore, maintain, and enhance ecological harmony. The principal guidelines for organic production are to use materials and practices that enhance the ecological balance of natural systems and that integrate the parts of the farming system into an ecological whole (23). ‘Organic’ is a labeling term that denotes products produced under the authority of the Organic Foods Production Act (26).

Over the past decades, organic agriculture has evolved in the United States from a small number of farmers who market locally and directly to consumers to a multi-billion dollar agricultural sector that trades domestically and internationally. Since 1990, the organic sector has been growing at an approximate annual rate of 20 percent (7). Industry sources estimate that organic food sales reached $9.3 billion in 2002 (4). In 1997 there were approximately 1.3 million certified organic acres in production in the United States (7). The estimated total number of organic farmers in the United States reached nearly 8,000 in 2000 -- an 18% increase over the previous year, according to a survey of organic farmers (21).

Through this period of sector expansion, private and state agencies have arisen which operate certification programs based on individually developed sets of organic standards. During the 1970s a number of organizations began to offer third-party organic certification. In 2000, 13 state and 36 private organic certification programs were in operation in the United States (24). This surfeit of certification agencies, each with their own standards, was perceived by the industry as a whole to be an impediment to overall market growth, both domestically and internationally. As a result, Congress passed the OFPA as Title 21 of the 1990 Farm Bill, establishing the process for the development of federally mandated organic standards. The OFPA mandated the USDA to establish organic standards in consultation with all constituents of the organic community represented on the NOSB. The USDA created the National Organic Program (NOP) as a part of the Agriculture Marketing Service (AMS).

Although the impetus for organic standards is primarily the for purpose of clarity and the further development of organics in the marketplace, the standards represent an agricultural production system founded upon ecological principles that promote a whole system approach to farming and minimize impacts on the environment. The NOP published the first proposed rule on December 16, 1997. As a result of the publication, the USDA was inundated with over 275,000 public comments regarding some sections of the rule, which did not reflect existing standards, or the consensus of the organic community as articulated by the NOSB. The unprecedented magnitude of public comments to the proposed rule made the USDA aware of the public support and deep concern for organic agriculture in the United States. A revised proposed rule was published in the Federal Register on March 13, 2000. The USDA received over 38,000 comments regarding the revised rule. The public comments were addressed in a final rule that was published on December 21, 2000. The NOP operates under the National Organic Program Standards (NOPS), which became effective April 21, 2001 and were fully implemented on October 21, 2002. All growers, handlers, and processors need to be fully compliant with these standards and certified by a USDA accredited certification organization. To date, 54 private certifiers and state programs have received accreditation under the NOP.

The NOPS sets forth the practice standards that are required for producers and handlers to label their products as organic. These National Organic Program Standards (NOPS) were based on responses to public comments; the NOSB’s recommendations; and various standards used by private certifiers, state programs, and the organic industry prior to passage of the OFPA. They represent a public-private partnership to promote the further growth of organic agriculture by setting consistent and uniform standards of production that consumers could identify and in which they could have confidence. The standards are expected to continue to evolve in response to sector growth and research in organic techniques.

Implications for Researchers

Cabbage being grown in a USDA NRI funded experiment evaluating various strategies of transitioning to organic production. The experiment is being conducted at The Center for Environmental Farming Systems in Goldsboro, NC.

The literature and research conducted in organic agriculture within the United States and abroad strives to be farmer-oriented, multidisciplinary, system-oriented, and to adopt a whole-farm perspective (11). These research goals are well-directed and purposeful, if not always achieved by the researchers. The NOPS are consistent with that approach to organic research and has additional implications for researchers in how they define their farming system and parameters within the system. With the implementation of the NOPS, the term ‘organic farming’ has a federally recognized standard of identity and it is the responsibility of researchers conducting on-farm or research center based experimentation on certified organic acreage to follow the NOPS. These standards are expected to facilitate the development of research projects that can be applicable to a broader base of organic producers.

Although the NOPS must be viewed in their entirety, the most relevant section for plant pathologists is the crop pest, weed, and disease management practice standard (24). The NOPS require that producers use a planned systems approach to crop protection. The approach encourages practices that improve soil health, promote good sanitation measures, employ cultural practices that enhance crop diversity, and advance the use of resistant plant varieties with site-specific applications and the control of pathogens through mechanical, physical, and cultural control methods. Non-synthetic biological, botanical, or mineral inputs may be employed to manage diseases; however, these substances are allowed only when the practices described above are insufficient to prevent or control diseases (Table 1). If such a substance is necessary for disease control, then a biological or botanical substance or a substance included on the National List of allowed synthetic substances (24) are acceptable for use in crop production. The use of materials on the National List must be documented by the producer in their organic system plan (24).

Table 1. Methods and materials permitted for plant disease management under the national organic program standards

Methods Crop rotations
Mechanical methods (e.g., pruning)
Fertility management
Classically bred resistant varieties
Vector control
Cultural practices
Materials Biologicals (e.g., Trichoderma spp,)
Botanicals (e.g., neem)
Minerals (e.g., kaolin)
Coppers, fixed-copper hydroxide, copper oxide, copper oxychloride, includes products exempted from EPA tolerance. Must be used in a way that minimizes accumulation in the soil.

Copper sulfate -- must be used in a way that minimizes accumulation in the soil.
Hydrated Lime
Hydrogen peroxide
Lime Sulfur
Horticultural oils in the narrow-range-petroleum derivatives predominately of paraffinic and napthenic fractions with 50% boiling points at 10 mm Hg of between 415°F and 440°F. Used as dormant, suffocating, and summer oils.
Elemental sulfur
Streptomycin -- for fire blight control in apples and pears only
Oxytetracycline calcium complex -- for fire blight cont
rol only.

Sources: 7 CFR 205.206, 7 CFR 205.601(i), OMRI Generic Materials List

Researchers must pay particular attention to sections of the rule that are undergoing further clarification within the NOP. One key example is the standard for manure and compost. The NOPS restrict the application of animal manure to a greater degree than any prior existing organic standard. Raw manure requires an interval of 120 days between application and crop harvest, where the edible portion of the crops destined for human consumption are in contact with soil, and 90 days for crops whose edible portion does not have direct contact with the soil surface or soil particles (24). To meet organic standards and harvest within this interval, animal manure must be composted by the process specified in the NOPS (24). The process includes an initial Carbon:Nitrogen ratio of between 25:1 and 40:1, and temperatures between 131°F and 170°F for three days in the case of in-vessel or static aerated pile system or for 15 days in the case of windrow composting system, during which period the materials must be turned a minimum of five times (7 CFR Part 205.203 (c)(2)). Crops that do not meet these specifications cannot be labeled as organic even if they are grown with compost practices accepted before the NOPS by organic certifiers. To address this anomaly, the United States Department of Agriculture created a task force, which includes NOSB members who have reviewed the rule and made recommendations to broaden the definition and consider alternative composting methodologies. The NOP is currently reviewing the policy and determining what response will be made to the task force’s recommendations. However, until such response is made, experimentation using animal materials conducted on certified acreage whether on-farm or on research stations should adhere to the rule if marketable ‘organic’ yields are intended to constitute a part of the experiment and data collection.

National List of Allowed and Prohibited Substances

While organic farming relies primarily on a systems approach and natural methods and inputs, a limited number of synthetic substances are allowed under the NOPS. The OFPA requires the Secretary of Agriculture to establish a National List of Allowed and Prohibited Substances (24) which identifies the synthetic substances that may be used, and the non-synthetic substances that cannot be used, in organic production and handling operations (24). This list is based on recommendations made by the NOSB, which in turn must consider criteria that are based on specific considerations of the agroecosystem, human health, and sustainability (27). The OFPA authorizes the NOSB to develop and forward to the Secretary of Agriculture a recommended proposed National List, and subsequent proposed amendments to it. This gives the NOSB greater authority than most other federal advisory boards because it limits the agency's decision-making power to determine which substances can be used in organic production systems. Individuals may petition the NOSB to evaluate substances for inclusion on or removal from the National List (27). The National List was published with both proposed rules and any subsequent amendment must also be posted in the Federal Register for public comment. The OFPA requires that the NOSB and the Secretary of Agriculture review every substance on the National List every five years upon the initiation of the NOP (27).

The National List divides substances into categories of use that include crop, livestock, and processed products. Therefore, substances may be allowed for use in processing of organic foods but prohibited from use in crop and livestock production. Additionally, within each category of use there may be specific restrictions that apply for the use of the substance within the crop production system. For example, copper sulfate may be used in crop production only in a manner that minimizes accumulation of copper in the soil (24).

The National List does not provide a comprehensive generic list of products that can or cannot be used within an organic farming system. For example, it does not include natural substances and biological controls. The NOPS does not provide a list of specific brand name agricultural inputs that comply with organic standards. The Organic Materials Review Institute (OMRI) is a non-governmental, nonprofit research and education organization whose mission is to publish and disseminate generic and specific (brand name) lists of materials allowed and prohibited for used in the production, processing, and handling of organic food and fiber (13). Brand name inputs used for organic production, processing, and handling are eligible to be listed with OMRI after they complete a rigorous review process that verifies compliance with the NOP rule. OMRI lists brand name products as a voluntary measure for educational purposes. While OMRI is broadly recognized in the organic community, listing is not mandatory or legally binding on subscribing certifiers. While the OMRI Brand Name Products List is not comprehensive, researchers experimenting with off-farm inputs can use it as a reference tool.

The Environmental Protection Agency (EPA) is working with the NOP to establish a labeling system for products that they approve as meeting the requirements of the rule. The NOPS refer to the EPA Lists of Inert ingredients to determine the fate of pesticide formulations in organic systems: EPA Inerts Lists 1 and 2 are prohibited, EPA List 3 is also prohibited unless specifically recommended as allowed by the NOSB, and EPA List 4 Inerts are allowed unless specifically prohibited (24).

In April 2001, the EPA released a draft of the proposed label identification program for public comment (29). Currently, the proposed program is under administrative review at the EPA and some aspects of the program may be modified. To date, it is not clear when this program will be implemented (22).

In the program, the EPA proposes to allow manufacturers to have their products reviewed for compliance with NOP regulations. If the EPA determines that a registrant’s product complies with the NOPS, then such a product could be labeled as NOP compliant. This is expected to help both growers and researchers identify the registered pesticides that are compliant with NOP regulation and available for use on the farm or for experimental purposes. Registrants of existing products who wish to gain EPA acceptance to add a NOP statement and symbol may submit an application for amended registration if the product meets all of the requirements as set forth by the EPA. The EPA will only review labeling submissions for pesticide products that are registered or proposed for registration. However, there are numerous pesticide products that are exempted under section 25(b) of Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). These products must contain only ingredients permitted under the NOPS and comply with all criteria of the National List. Such products may be in violation of FIFRA if they misrepresent on the label their status under the NOP (26).

Research Needs and Opportunities

Despite the fact that the organic sector is the fastest growing agricultural sector as well as one of the most innovative, public investment in organic research projects within the USDA and land grant universities has been negligible at best. In a survey of the Current Research Information System (CRIS) USDA database for year 1995, the Organic Farming Research Foundation (OFRF) found, both numerically and fiscally, that less than one-tenth of one percent of USDA’s research portfolio had a strong organic focus (10). They also found that within the estimated 885,863 available research acres in the land grant system, only 0.02 percent or 151 acres, were being used for certified organic research (19). The report noted the excellent work being done in such states as North Carolina, Minnesota, Ohio, West Virginia, and Iowa and, in contrast, the absence of organic programs in eleven states. The USDA’s Sustainable Agriculture Research and Education (SARE) program has turned out to be one of the major sources of federal support for organic farming research projects with approximately 12 percent of all of projects funded having an explicit organic focus (19).

Organic research requires a multidisciplinary and holistic systems approach. The central underlying assumption of a systems approach is that agroecosystems are complex, and interrelationships among environmental conditions, management, and biological processes are important in determining outcomes such as yield, pest pressure, and environmental impacts (6). Organic farming research places a greater emphasis on involving farmers in the research process and incorporating on-farm experimentation to complement work being conducted on research stations (1,19). Numerous studies have successfully incorporated some or all of these objectives and offer insight to researchers seeking an alternative approach to more traditional reductionist studies (1,2,3,5,8,9,12,14,15,16,17,20,29). Perhaps the most important defining characteristic of agroecosystem studies is that they offer the opportunity to test broad, integrated hypotheses (6).

To date, organic farming systems research efforts have been limited to those conducted on existing organic farms, either analyzing and characterizing aspects of the farm system, or as a part of long-term farming systems research plots at a handful of non-profit institutions and universities (1,2,3,8,9,14,15,16,20,28,30,31). One of the major limitations of organic farming systems research is the lack of stable institutional support for such efforts. Based on the OFRF report, Colorado, Georgia, Illinois, Iowa, Kentucky, Michigan, Minnesota, New Jersey, North Carolina, Ohio, Washington, and West Virginia had research land that was either organically certified or in the process of transitioning land for organic certification (19). Some of these institutions had interdisciplinary teams of researchers contributing expertise in soil nutrient dynamics, weeds, microbial ecology, soil micro- and macro-fauna, plant pathology, horticulture and agronomy (19). Since the publication of the OFRF report, a number of universities have examined their institutional capacity to conduct research for organic farmers. For example, the University of Florida has established a Center for Organic Agriculture and is in the process of certifying 40 acres at a newly-established research center in Citra, Florida.

Recently, the USDA also has increased their efforts in organic research. At the Crop Improvement and Protection Research Center in Salinas, California there are 17 acres of land devoted to certified organic research. In 2003, 20 acres in Ames, Iowa and 22 acres in Beltsville, Maryland will be certified organic for research purposes at those USDA facilities (18). Recently, a survey of researchers within the USDA was conducted to determine their involvement in organic research. Of the 135 researchers who responded to the survey, 58 work explicitly on organic projects, a noted improvement over the 1995 OFRF survey results of the USDA’s CRIS database.

The Scientific Congress on Organic Agriculture Research (SCOAR) is a project initiated by OFRF to bring together producers, researchers, extension personnel, and other individuals involved in organic farming and research to participate in the development of a national research agenda for organic agriculture. Over 900 individuals have been involved in a series of regional and national meetings to develop research priorities and programs that meet the needs of organic farmers and the industry. Table 2 summarizes the list of priorities that are of importance to plant pathologists. A detailed list of all of the priorities can be found at The list is a comprehensive overview of the national needs of organic producers and provides a good starting point for researchers eager to explore some of the pressing needs of the organic industry. Moreover, identifying and organizing organic producers in one’s region in an advisory capacity is an effective way of insuring that the research objectives are meeting the needs of local producers (3,12).

Table 2. List of Plant Pathology Related Priorities Generated by SCOAR Members

a. Functionally identifying soil microbial communities and ways to manage microbial dynamics to enhance nutrient cycling and disease suppression.
b. Systemic approaches to weed and pest management.
c. Breeding crops for disease and insect resistance, good yield in a biologically diverse system, compatibility with intercrops, good response to organic fertility sources, horizontal resistance.
d. Crop rotation effects on soil microbiology and results for crop health.
e. Soil management strategies for disease suppression.
f. Compost effects on organic cropping systems.
g. Alternatives to copper and sulfur fungicides in organic fruit production.
h. Probiotic research investigating the potential to replace pathogenic microbes with beneficial ones.
i. Long-term soil and human health effects of applying organically acceptable pesticides such as sulfurs, oils, copper fungicides, and botanicals.
j. Developing biological seed treatments for fungus control.
k. On-going materials review for inclusion on or removal from the National List.
l. Alternatives to chlorine in processing methods.
m. Postharvest treatments for organic fruits and vegetables.

Funding opportunities for organic research are expected to increase with the full implementation of the National Organic Program. The Farm Security and Rural Investment Act of 2002, Section 7218, established the Organic Agriculture Research and Extension Initiative, a program that budgets $3 million per year in each of the next five years (FY 2004-2008) to fund organic farming and marketing research. In addition, other USDA programs such as SARE and the National Research Initiative, as well as the National Science Foundation, have funded organic research projects. Since 1990, OFRF has awarded nationally over $1 million exclusively on organic research projects. Numerous private foundations, corporations, and individuals have contributed to and supported research efforts nationwide. Increases in current and future levels of funding are critical for further expansion and continual growth of organic farming in the United States.

Temporary Variances for Research

The NOPS allow for temporary variances from specific requirements of the rule for research and experimentation on certified farms. The Administrator of the program can grant a temporary variance for practices used for the purpose of conducting research or trials of techniques, varieties, or ingredients used in organic production or handling (24). The application process and procedures for variances to the NOPS on organic farms have not been developed. In the meantime, researchers who are interested in conducting experiments on certified organic farms should refer to and follow the NOPS.


The United States organic industry has experienced phenomenal growth through the past decade. In an era when many conventional producers are facing economic hardships and approximately 35% of farms are in economic jeopardy and government payments constituting a substantial portion of farm income (25), organic production may offer new economic possibilities for farmers. The development and implementation of the USDA’s National Organic Program Standards are expected to aid in the expansion of the organic industry and the development of research programs that address organic farmer’s needs on both regional and national levels. Organic farmers need knowledgeable and experienced researchers to address their research priorities using a multidisciplinary, holistic, systems approach. Researchers need the commitment of their institutions and public and private funding sources to provide the resources needed to carry out long-term systems research projects. Finally, the demands and values of consumers need to be acknowledged, respected, and reflected as a driving force behind the continued growth and development of organic farming.

Disclaimer and Acknowledgements

The authors wish to thank W. Lockeretz, M. Mesh, E. Brown-Rosen, and J. Sooby for reviewing this manuscript.

The views and opinions expressed in this paper are those of the authors only and do not reflect the views of the United States Department of Agriculture, the National Organic Standards Board, the University of Florida, or the Organic Materials Review Institute.

Additional Resources

Alternative Farming Systems Information Center

Appropriate Technology Transfer for Rural Areas

Environmental Protection Agency

Contact for NOP labeling proposal (e-mail)

Kerr Center for Sustainable Agriculture

Organic Farming Research Foundation (e-mail)

Organic Farming Research Foundation

Organic Materials Review Institute

Organic Trade Association

National Organic Program

Administrator NOP (e-mail)

Rodale Institute

Rural Advancement Foundation International

Sustainable Agriculture Research and Education Program

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