Can I Use This Input on My Organic Farm?

eOrganic authors:

Nick Andrews, Oregon State University

Brian Baker, Organic Materials Research Institute

Jim Riddle, University of Minnesota

Assessing Inputs

The National Organic Program (NOP) final rule (United States Department of Agriculture [USDA], 2000) emphasizes the use of preventive and cultural methods such as crop rotation, cover cropping, sanitation measures, and nutritious feed rations to build soil fertility, prevent pest problems, and maintain livestock health. In fact, the NOP requires that management practices to prevent pests, weeds and diseases, including soil-building crop rotations; sanitation measures to remove disease vectors, weed seeds, and pest habitat; selection of site-suitable and resistant plant and livestock species and varieties; release of pest predators and parasites; development of habitat for pest predators; lures, traps and repellants; mulching, mowing, grazing, mechanical, flame, and/or hand weeding; and cultural practices to prevent weed, pest and disease problems must be implemented, and found to be insufficient, prior to the use of any input.

Many organic farmers save money and produce high-quality crops with little or no off-farm inputs, but most producers rely on at least some purchased inputs. Purchasing inputs brings up the question: Is this product allowed? Given that most agricultural inputs are not produced with NOP standards in mind, those of us trying to meet the standards have to ensure that we use only approved products.

With full implementation of the National Organic Program regulations on October 21, 2002, it’s the National Organic Program (NOP) that allows or prohibits a material, via the National List of Allowed and Prohibited Substances (National List). This is a generic materials list. The NOP does not publish a brand name materials list. Brand name lists evaluate a formulated product’s compliance to the requirements of the National List, but do not carry any regulatory weight. Of course, you are free to use brand name lists for guidance (as most organic certifiers do), but certification agencies are responsible for evaluating materials to be used by producers and handlers for compliance with the National List requirements. As a producer, this means that you must submit a list of all inputs you use or intend to use as part of your Organic System Plan, and your certification agency will determine if the substances are allowed for organic production.

Making Sense of the National List

The portion of the NOP concerned with the National List begins at section 205.105 (see “NOP on materials” below). Simply put, it says we cannot use products with synthetic ingredients for organic crop or livestock production, unless they are specifically allowed and appear on the National List (see definition in “NOP on materials”). Some nonsynthetic (natural) substances are also prohibited (see sections 205.602 and 205.604). In other words, synthetic materials cannot be used unless they are specifically approved, and natural materials can be used unless they are specifically prohibited. The National List specifies the allowed synthetic substances and prohibited nonsynthetic substances (see section 205.601), along with specific restrictions, or annotations, regarding the source or use of the substance. The National List doesn’t include numerous natural, nonsynthetic substances, such as gypsum, limestone, or rock phosphate, which are allowed by definition.

Reading Labels

Next stop is the product label. If the ingredients are nonsynthetic and not included as prohibited in section 205.602, they are allowed. If there are synthetic ingredients, check to see if they are specifically allowed. Be sure to check section 205.601 for crop and 205.603 for livestock annotations. These annotations are where I’ve seen some challenges for growers. The annotations often regulate or place certain restrictions on the manufacturing processes or the use of a material. For example, Lidocaine is allowed as a local anesthetic, but its use requires a withdrawal period of 90 days for livestock intended for slaughter and seven days for dairy animals. Compliance with restrictions must be documented when an annotated material is used.

Reading the label may not be enough to determine if a product complies with National List annotations. Labels frequently do not provide all the information about the manufacturing process. For example, liquid fish products are allowed as plant or soil amendments (see §205.601.j.7). They “can be pH adjusted with sulfuric, citric or phosphoric acid. The amount of acid used shall not exceed the minimum needed to lower the pH to 3.5.” Ingredient lists on liquid fish do not address this issue. Before purchasing or using a liquid fish product, a grower should contact the manufacturer or confirm that the product is listed on a brand name list of NOP compliant products.

Non-active or inert ingredients in pesticide formulations are classified according to the level of toxicological concern. EPA has changed how it lists inert ingredients, and the NOP has taken over the maintenance of the list of substances used as inert ingredients that EPA determined to be of minimal concern prior to 2004. To be NOP compliant, all synthetic inert ingredients in pesticides must be classified as minimum risk, appear specifically on the National List, or be used in passive pheromone dispensers. Inert ingredients do not appear on labels, so verifying compliance with this annotation requires the cooperation of the pesticide registrant.

If you contact manufacturers, try to get answers in writing or at least record what you learn. If you are unsure of the information that you need, contact your certifier for guidance and they should be able to help you ask the right questions. When considering a new product, be sure to plan ahead. In trickier cases, a simple “yes” or “no” answer may not be possible over the phone.

As the saying goes, “The devil is in the details.” It’s these tricky cases that cause the headaches. It’s tempting to just refer to a brand name materials list and use those products. But remember, just because a product is not on a particular brand name materials list does not necessarily mean that it is prohibited by the NOP. Also remember that only the NOP carries regulatory weight; all other lists are based on evaluations of compliance to the rule. 

Brand Name Material Lists

The NOP established a policy that each Accredited Certifying Agent (ACA, certifier) is responsible for conducting its own reviews of inputs for agricultural production, such as formulated pesticides and soil amendments. The NOP also allows certifying agents to recognize reviews conducted by other certifying agents and competent third-party reviewers as described in a letter to organic certifiers on verification of materials (Robinson and Bradley, 2008), and later confirmed by a Policy Memo in the NOP Policy Handbook. All ACAs are required to verify, along with their clients, that all materials used or planned for use by certified organic operations comply with the NOP. To paraphrase, ACAs have three options available to determine whether branded or formulated products comply:

  1. ACAs can contact the manufacturer to obtain disclosure of the contents of the product and verify that they all comply;
  2. ACAs may consult with another ACA that has reviewed the information and accept their determination that the material is NOP compliant; or
  3. ACAs may consult with a reputable third party source, such as the Environmental Protection Agency (EPA) or the Organic Materials Review Institute (OMRI), that reviews materials for compliance with the NOP regulation.

ACAs must document their determinations and verify that the inputs are used according to the regulation. ACAs must either have the capacity and expertise to review products, or contract with organizations accredited do so. Many ACAs contract with OMRI, a non-profit initially established by certifiers specifically for that purpose. The Washington State Department of Agriculture (WSDA) also reviews products according to the NOP and publishes a list of brand name products that other ACAs use. These lists are not comprehensive, so there may be other brand name products that can be used. However, in order to be sure that a product complies, the manufacturer must fully disclose all ingredients and manufacturing processes to an ACA or a third party contracted by the ACA. All ingredients must comply with the standards described above.

One Step at a Time

Before using a new product, check for recent OMRI or WSDA approval of the product. If it isn’t listed, follow these steps:

  1. Evaluate each label ingredient for compliance with the NOP and any annotations on the National List. The OMRI Generic Materials List may also be helpful.
  2. Contact the manufacturer if necessary.
  3. Document compliance with all NOP crop and livestock annotations.

Since this process can take some time, be sure to plan ahead when developing or updating your Organic System Plan (OSP). Keep records of all communications with input manufacturers, certifiers, and input review services. Keep labels, receipts, shipping invoices, and input application records. The documentation required to demonstrate compliance with the NOP can seem daunting and sometimes takes time away from working the land. However, this careful verification gives organic consumers confidence in the organic standard they have grown to trust.

NOP Citations on Materials

§ 205.105 Allowed and prohibited substances, methods, and ingredients in organic production and handling.
To be sold or labeled as “100 percent organic,” “organic,” or “made with organic (specified ingredients or food group(s)),” the product must be produced and handled without the use of:
(a) Synthetic substances and ingredients, except as provided in § 205.601 or § 205.603;
(b) Nonsynthetic substances prohibited in § 205.602 or § 205.604;
(c) Nonagricultural substances used in or on processed products, except as otherwise provided in § 205.605;
(d) Nonorganic agricultural substances used in or on processed products, except as otherwise provided in § 205.606;
(e) Excluded methods, except for vaccines, provided that the vaccines are approved in accordance with § 205.600(a);
(f) Ionizing radiation, as described in Food and Drug Administration regulation, 21 CFR 179.26; and
(g) Sewage sludge.

§ 205.206 Crop pest, weed, and disease management practice standard
(e) When the practices provided for in paragraphs (a) through (d) of this section are insufficient to prevent or control crop pests, weeds, and diseases, a biological or botanical substance or a substance included on the National List of synthetic substances allowed for use in organic crop production may be applied to prevent, suppress, or control pests, weeds, or diseases; Provided, That, the conditions for using the substance are documented in the organic system plan.

§ 205.601 Synthetic substances allowed for use in organic crop production.
In accordance with restrictions specified in this section, the following synthetic substances may be used in organic crop production: Provided, That, use of such substances do not contribute to contamination of crops, soil, or water. Substances allowed by this section, except disinfectants and sanitizers in paragraph (a) and those substances in paragraphs (c), (j), (k), and (l) of this section, may only be used when the provisions set forth in §205.206(a) through (d) prove insufficient to prevent or control the target pest.

§ 205.602 Nonsynthetic substances prohibited for use in organic crop production.
The following nonsynthetic substances may not be used in organic crop production:
(a) Ash from manure burning
(b) Arsenic
(c) Calcium choloride, brine process is natural and prohibited for use except as a foliar spracy to treat a physiological disorder associated with calcium uptake.
(d) Lead salts
(e) Potassium choloride-unless derived from a mined source and applied in a manner that minimizes chloride accumulation in the soil.
(f)Rotenone (CAS #83-79-4).
(g) Sodium fluoaluminate (mined).
(h) Sodium nitrate-unless use is restricted to no more than 20% of the crop's total nitrogen requirement; use in spirulina production is unrestricted until October 21, 2005.
(i) Strychnine
(j) Tobacco dust (nicotine sulfate)

§ 205.604 Nonsynthetic substances prohibited for use in organic livestock production.
The following nonsynthetic substances may not be used in organic livestock production:
(a) Strychnine
(b)-(z) [Reserved]

NOP definition of "synthetic" -  "A substance that is formulated or manufactured by a chemical process that chemically changes a substance extracted from naturally occurring plant, animal or mineral sources, except that such term shall not apply to substances created by naturally occurring biological processes."

References and Citations

Additional Resources


Published April 1, 2021

This is an eOrganic article and was reviewed for compliance with National Organic Program regulations by members of the eOrganic community. Always check with your organic certification agency before adopting new practices or using new materials. For more information, refer to eOrganic's articles on organic certification.