National Organic Standards Board 

Crops Subcommittee Proposal 

Biodegradable Biobased Mulch Film 

August 13, 2021 

I. Summary of biodegradable biobased mulch film 

The NOP rescinded policy memorandum 15-1 in October 2019, stating that it was redundant with 

current regulations. The requirement for 100% biobased feedstocks is articulated in the preamble of the 

final rule and the status quo remains. Removal of the policy memorandum provides an opportunity for 

the NOSB to revise the current definition (§ 205.2) to consider reducing the biobased content 

requirement. The Crops Subcommittee is now planning to vote on an annotation at the Fall 2021 

meeting addressing biodegradable mulch (BDM) film that is not 100% biobased. 

II. Discussion 

Biodegradable biobased mulch film has been on the National List of approved synthetic substances 

since September 30, 2014, based on an October 2012 NOSB recommendation. Historical information on 

this material is as follows: 

Reference on the National List: § 205.601(b) As herbicides, weed barriers, as applicable (2) Mulches 

(iii) Biodegradable biobased mulch film as defined in §205.2. Must be produced without organisms or 

feedstock derived from excluded methods. 

Technical Report: 2012 TR; 2015 Report; NOP Policy Memorandum 15-1; Supplemental Technical 

Evaluation Report 2016 

Petition(s): 2012 

Past NOSB Actions: 10/2012 NOSB Recommendation; Memo to the NOSB with Report on 

Biodegradable Biobased Mulch Films in Organic Crop Production (Michigan State University, September 

2019) (pdf). 

Recent Regulatory Background: Final Rule published 09/30/14 (79 FR 58655); Sunset renewal notice 

published 10/08/2019, 84 FR 53577 

Background from Subcommittee 

Biodegradable biobased mulch films were approved for placement on the National List of approved 

synthetics (Biodegradable Mulch Film Made from Bioplastics) without detailing if non-biobased content 

would be allowed. The vast majority of mulch films in this category contain 20% or less of biobased 

materials (i.e., carbon sources are ~80% petroleum derived). There are some products that might meet 

the biobased aspect of this material’s definition on at §205.2, but they are either not biodegradable or 

are not used in production due to brittleness or other production issues. 

In January 2015, the National Organic Program issued Policy Memorandum 15-1, to clarify that 

biodegradable biobased mulch film must not contain any non-biobased synthetic polymer feedstocks. 

The NOSB requested a limited scope technical report (TR) in 2016. The questions asked for this 

limited scope TR from 2016 were as follows: 

1. What is the effect on overall soil health, including soil biology, when this materialbiodegrades? 

2. What is the cumulative effect of the continued use of this biodegradable biobased mulch film, 

on soil nutrient balance, soil biological life, and soil tilth, when used in the same area of the 

field for 3-5-10 years? 

3. What effect does the breakdown of these polymers have on soil and plant life as well as 

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livestock that would graze either crop residues or forages grown the subsequent year after this 

mulch film was used? 

4. Are there different cropping systems, climate, soil types or other factors that affect the 

decomposition rate (Examples would be long cold winters, or exceptionally dry conditions, such 

as found in a desert)? 

5. Are there metabolites of these mulches that do not fully decompose, and if so, is there an effect 

upon soil health or biological life? 

The TR focused on biobased biodegradable mulches that contain polymers and the soil and crop health 

effects they may have as they biodegrade. This supplemental TR was inconclusive, since research on 

these materials is currently limited, and the questions above were not answered to the NOSB crop 

subcommittee’s satisfaction. 

An argument can be made that even though the non-biobased polymers degrading into the soil 

originate from petroleum (a nonrenewable fossil fuel), the use of this product could be considered 

environmentally friendly because: 

• Many organic production systems rely on enormous amounts of fossil fuel-derived plastic, 

mostly polyethylene (PE) films, to produce organic crops; 

• PE films likely shed micro plastics and leach chemicals into organic soil over the growing 

season; 

• Before and during removal, PE films can tear and breakdown, leaving plastic in the soils or 

migrating off-site into aquatic habitats; 

• PE films are generally not recyclable due to contamination by soils or the lack of recycling 

infrastructure; 

• Plastic used in annual production systems end up in landfills; 

• Biodegradable mulches potentially save labor and time, and likely fuel, since the mulch does 

not have to be removed from the field and transported for disposal; 

The current listing of biodegradable mulch on the National List is aspirational: there are no products on 

the market that are commercially viable made from 100% biobased carbon sources (i.e., no petroleum). 

In fact, some public commenters have recommended that BDM films be taken off the National List 

since the 100% biobased requirement essentially prohibits use of these materials. Despite the lack of 

products meeting the annotation, the NOSB reviewed this material for its five-year sunset renewal in 

2017 and decided to relist it as written, with the understanding that there were no products on the 

market that were commercially viable made from 100% biobased materials. The Crops Subcommittee 

felt more information was needed that addressed the key questions above before considering a change 

to the annotation. The Crops Subcommittee also felt that if biodegradable mulch remained on the 

National List manufacturers would be able to develop a product that met the requirement of 100% 

biobased “ingredients”, which was the preferred outcome. 

The National Organic Program also reached out to Dr. Ramani Narayan, a researcher with the 

Department of Chemical Engineering and Materials Science at Michigan State University, to provide 

more information beyond the Technical Report, which was completed in 2016, to the NOSB. The focus 

of Dr. Narayan’s report is the biodegradability of both biobased and petroleum-based mulch films with 

limited research on the effect of these products degrading into the soil over time. Section 2.7 of the 

reportstates: 

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Environmental studies have not shown any adverse impacts associated with the incorporation of 

biodegradable mulch films (BDMs) into the soil to date. More research is needed to monitor any 

potential formation of terrestrial micro and nanoplastics from biodegradable mulch films and 

ensure that there is no residual soil ecotoxicity. There is need for tuning the physicochemical 

properties of the biodegradable mulch films with the needs of specific cropping systems and 

climates .... Sintim et al. showed that there was no significant effect on soil health over two 

years of monitoring and that the soil microbial communities did not differ much either. They 

found significant enrichment in bacterial and fungal gene copies under BDM treatments over 2 

years, but no significant change under PE and no mulch. Another important observation was 

that repeated tillage of BDMs into the soil across 4 years did not impact crop yield significantly 

and had no major effect on crop quality. 

While this section points out possible negative issues with some polymers used in the biodegradable 

mulch, the majority of the report focused on the positive aspects when the mulch does biodegrade. The 

report also discussed current regulations that protect organic integrity and would not allow the use of 

excluded methods (some of the polymers are extracted from petroleum through the use of bacteria 

created through excluded methods) and do not allow materials to be used that “contribute to 

contamination crops, soil or water.” Organic producers in the European Union are allowed to use 

petroleum based biodegradable mulch with no requirement on the percentage of bio-based ingredients. 

The EU will be reviewing these mulches in 2024 with possible changes to their annotation. 

Key concerns of current and past NOSB members 

include the possibility of soil, aquatic, and other 

environmental contamination by partially 

decomposed BDM films even if the materials pass 

ASTM laboratory-based standards. Of particular 

concern to NOSB members is the possibility that 

BDM films will not decompose thoroughly in dry or 

cold environments where there is less biological activity in 

soils. A related concern is that BDM films ploughed into 

soils may be out of reach of peak biological activity to break 

it down. For example, most soil biological activity occurs in 

the top 4-6 inches, with only a small fraction below that 

level. If ploughing results in BDM film plastic mixed into soil 

7-10 inches deep, there may be fewer microbiotic fauna 

available to consume BDM carbon sources. Figures 2 and 3 

show examples of relatively complete biodegradation after less than one year and another case where 

visible material after 2 months “burial” (source: https://eorganic.org/node/8260). 

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Organic Strawberry PE Film Plasticulture (Source: 

https://ucanr.edu/blogs/blogcore/postdetail.cfm?p 

ostnum=31015&) 

Extensive public comments and up-to-date 

scientific reviews have been submitted to the 

NOSB, and in some cases submitters note 

sampling and/or other analytic methods are not 

yet developed enough to answer all questions 

about potential residues in soil. 

The Board has also weighed the merits of 

comparing the risk to soils and the environment 

from BDM films versus risk from PE films. Board 

members are torn on this issue. Use of plastic in 

organic production is increasing rapidly. Many 

small- and large-scale growing systems, 

such as organic “plasticulture” strawberry 

production, are highly dependent on PE films, with 

thousands of acres of plastic used annually to 

essentially containerize soil, resulting in enormous 

amounts of plastic waste and agricultural soil and 

general environmental contamination (see figures). 

For example, the Monterey County Regional Waste 

Management District in California receives 5,700 

tons (11.4 million lbs.) of agricultural plastic 

annually. Based on the acreage of organic 

strawberries, (approximately 20%), up to ~1-2 

million lbs. is likely from organic fields each year. 

Board members are also concerned about the 

Monterey County Agriculture 

Plastic Waste – Organic and 

Conventional. Source: P. Krone, 

NOAA 

precedent of allowing petroleum-derived products 

to be added directly to soils. The comparative risk of the two production aids leaves 

some organic community members uncomfortable. In essence, the thinking is “I don’t think the reason 

to add a new material to the National List should be because we’re trying to mitigate the harms caused 

by another NL material.” 

Precedents of Allowing the Addition of Petroleum Products to Soil 

The National List currently allows the use of petroleum-derived products on organic soils. For example, 

horticultural mineral oils used in crop production are refined from petroleum. Mineral oils are closer in 

chemistry to petroleum jellies and paraffin, versus 

other more volatile and toxic petroleum constituents. 

However, these materials pose some environmental 

and health risks, and their use on crops results in 

direct entry into soil ecosystems. 

The NOSB is also proposing allowance of paper pots 

as planting aids, with the listing to read as follows: 

Paper-based crop planting aid. A material that is 

comprised of at least 60% cellulose-based fiber by 

weight, including, but not limited to, pots, seed tape, 

and collars that are placed in or on the soil and later 

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incorporated into the soil, excluding biodegradable mulch film. Up to 40% of the ingredients can be nonsynthetic, other permitted synthetic ingredients at §205.601(j), or synthetic strengthening fibers, 

adhesives, or resins. Contains no less than 80% biobased content as verified by a qualified third-party 

assessment (e.g., laboratory test using ASTM D6866 or composition review by qualified personnel). 

Added nutrients must comply with §§205.105, 205.203, and 205.206. 

This proposal requires 80% biobased content, but allows 20% of the material to be non-biobased, 

potentially including nylon and other non-biodegradable plastics in the paper pots. The paper-pot 

proposal is notable because it allows the direct application of non-biodegradable plastics to soil, although 

the long-term hope is that future products will be 100% biobased. Paper-pot production aids are 

generally used by small farmers and their contribution to soil plastics is likely to be small compared to the 

thousands of acres of soil covered by PE films and their possible future BDM film replacements. 

Possible Use Restrictions 

The Board has considered several options to guide use of BDM films with less than 100% biobased 

content, if they are approved. Specifically: 

1. Allow BDM film use followed by ploughing into soil (with some consideration for off-site 

transport), with monitoring and assessment to determine whether there are adverse 

impacts; 

2. Restrict BDM film use based on soil types and climates where the BDM film may not 

biodegrade rapidly; 

3. Allow BDM film use but require that it be gathered up at the end of the season followed by 

on-farm or off-farm composting. 

In response to public comments, the Crops Subcommittee has concluded that Option 1, above, is the 

only reasonable option on which to vote. Soil types and climate are complex, and it is not possible to 

pre-identify regions and growing practices where use of the BDM films may or may not work (Option 2). 

Finally, Option 3 does not work because the films become brittle toward the end of the season and 

cannot be removed intact for later composting. 

Public commenters at the April 2021 meeting remain divided, although many farmers and certifiers 

agreed reducing the requirement of 100% biobased content by a small margin is reasonable. Groups 

supporting the change included, Oregon Tilth, OWPC, MOSA, PCO, QCS, VOF, NOFA. Many farmers also 

supported the change. Those opposed included NOC, BP, MOGFA, Cornucopia, and OEFFA, raising 

concerns about the product being “not ready for prime time”, the potential for environmental 

contamination, the replacement of plant-based mulches, and that use may not reduce use of PE film-based 

plasticulture on soils. 

III. Proposal 

Weighing the risks and benefits of using PE and BDM films, the Crops Subcommittee proposes to allow 

BDM films that are at least 80% biobased by weight, with the remaining 20% by weight consisting of 

materials that meet one of the following composting standards: ASTM D6400, ASTM D6868, EN 13432, EN 

14995, or ISO 17088 (all incorporated by reference; see § 205.3). The CS understands that this 

recommendation is still aspirational in the sense that no current BDM films meet the 80% biobased 

content criteria. However, several manufacturers have reported that producing 80% biobased film may be 

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feasible, and this proposal sets a realistic goal. The CS recommends that use of >80% biobased material be 

required if and when these materials become available, The CS also recommends ongoing monitoring of 

new research on BDM and other plastic films and that the NOSB should consider changes to this 

annotation as information and new products become available. 

The CS proposes the following annotation change for biodegradable biobased mulch film: 

§205.601 Synthetic substances allowed for use in organic crop production. 

(iii) Biodegradable biobased mulch film as defined in §205.2. Must be produced without organisms or 

feedstock derived from excluded methods. 

§205.2. 

Biodegradable biobased mulch film. A synthetic mulch film that meets the following criteria: 

(1) Meets the compostability specifications of one of the following standards: ASTM D6400, ASTM D6868, 

EN 13432, EN 14995, or ISO 17088 (all incorporated by reference; see § 205.3); 

(2) Demonstrates at least 90% biodegradation absolute or relative to microcrystalline cellulose in less than 

two years, in soil, according to one of the following test methods: ISO 17556 or ASTM D5988 (both 

incorporated by reference; see § 205.3); and 

(3) Must be at least 80% biobased with content determined using ASTM D6866 (incorporated by 

reference; see § 205.3). 

Vote in Crops Subcommittee 

Motion to accept the biodegradable biobased mulch film annotation recommendation. 

Motion by: Asa Bradman 

Seconded by: Brian Caldwell 

Yes: 7 No: 1 Abstain: 0 Absent: Recuse: 0 

Approved by Rick Greenwood, Crop Subcommittee Chair, to transmit to NOP August 15, 2021. 

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