USDA's Animal and Plant Health Inspection Service did not declare Darling 54 American chestnut free of every environmental, ecological, or restoration risk. APHIS made a narrower comparative finding: Darling 54 is unlikely to pose a greater plant-pest risk than the nonmodified comparator, so it is no longer subject to the agency's regulations in 7 CFR part 340 governing the introduction of certain genetically engineered organisms.
The status changed on August 28, 2026. The evidence path matters because the original 2020 petition named Darling 58, later analyses showed that essentially all offspring in the initial crosses came from Darling 54 after a 2016 labeling error, and the applicant submitted a corrected petition in 2024. APHIS then reviewed new information, revised its plant pest risk assessment, reopened public comment, and issued the Darling 54 decision.
The question this map answers
What evidence and state transitions connect the original Darling 58 petition to Darling 54's final nonregulated status, and which conclusions remain outside the scope of APHIS's plant-pest determination?
MyMap observed the APHIS announcement, Federal Register notice, amended petition, and agency petition-review explanation at 4:20 AM Pacific Time on August 30, 2026. Nonregulated status here means the article is no longer regulated under the identified APHIS plant-pest provisions. Comparator means the nonmodified organism against which APHIS assessed relative plant-pest risk. Tolerance is the source's trait description; it is not the same word as immunity, eradication of chestnut blight, or proven restoration success.
The identity correction is part of the evidence, not a footnote
APHIS received the original petition on January 21, 2020. It named Darling 58 and sought a determination that the genetically engineered, blight-tolerant American chestnut should no longer be regulated under 7 CFR part 340. APHIS published the petition for comment that August and later prepared a draft plant pest risk assessment and draft environmental impact statement.
The record changed after identity work in 2023. APHIS says multiple analyses showed that essentially all offspring from the initial crosses were derived from Darling 54 because of a labeling error in 2016. The agency also says Darling 54 and Darling 58 were produced at the same time, with the same transgenes in the same genetic background, and express the same protein products. Because nearly all phenotypic information in the original petition came from Darling 54 offspring, SUNY-ESF submitted an amended petition in August 2024 to correct the line name and add updated data.
That does not justify silently replacing 58 with 54 in the old record. A reproducible evidence map keeps the submitted identity, the later test result, the reason for correction, and the revised document as distinct events. Otherwise, a reader cannot tell whether evidence was generated from the named event or attributed after reconciliation.
Public-comment totals are not vote totals
The Federal Register notice describes four public-input stages:
| Review stage | Total comments received | Posted comment records | Source-stated pattern |
|---|---|---|---|
| 2020 petition | 4,337 | 4,321 | majority favored deregulation |
| 2021 EIS notice of intent | 3,968 | 3,964 | large majority opposed |
| 2022 draft PPRA and draft EIS | 30,455 | 9,289 | majority favored; many opposed |
| 2025 revised petition, PPRA, and EIS | 174,116 | 4,115 | large majority opposed; many supported |
Those pairs measure different things. Regulations.gov can assign one posted comment ID to an uploaded submission that represents multiple comments, so comments received and posted records cannot be substituted for each other. The support/opposition descriptions summarize the agency's categorization; they are not a referendum whose largest side mechanically determines regulatory status.
APHIS says its final determination used the corrected petition, available scientific data, its plant pest risk assessment, and comments on the original and revised records. The map therefore routes comments into the review evidence lane, not directly into a yes-or-no outcome box.
The EIS path stopped while the plant-pest review continued
After the 2024 correction, APHIS revised both the draft plant pest risk assessment and draft environmental impact statement. It published those revised materials with the amended petition on June 6, 2025 for a 45-day comment period.
On August 18, 2025, APHIS withdrew its notice of intent and terminated work on the EIS. In a separate agency explanation of its petition practices, APHIS said the petition decision is confined to factual and scientific information relevant to whether the organism is a regulated article under its plant-pest authority. When the organism is unlikely to pose greater plant-pest risk than its comparator, APHIS says it lacks jurisdiction under that process and must issue a nonregulated-status determination.
This creates two different state lines: the EIS work was terminated, while the plant-pest petition review continued through a revised PPRA, public comments, and a final determination. Drawing one arrow called environmental review completed would be inaccurate. The final notice expressly identifies the PPRA and comments as decision inputs and says EIS work ended the prior year.
What changed on August 28
APHIS's notice was signed August 24, announced August 27, published August 28, and says the regulatory status is recognized as of August 28. Event date, announcement date, publication date, and effective status date are therefore related but not interchangeable.
The source-stated effect is that Darling 54 is no longer subject to 7 CFR part 340 regulation governing introduction—defined in the notice as importation, interstate movement, or environmental release—of the covered genetically engineered regulated articles. APHIS bases that effect on its finding that Darling 54 is unlikely to pose a greater plant-pest risk than the nonmodified comparator.
The finding is comparative and jurisdiction-specific. It does not establish that every planting site is suitable, that blight tolerance equals immunity, that the tree will restore historic forest composition, that gene flow or long-term ecological outcomes are known at every scale, or that every other federal, state, Tribal, local, land-management, or private requirement has been satisfied. The reviewed final notice does not publish a deployment plan or forecast restoration performance.
Confirmed, derived, and still unknown
The controlling sources confirm the petition and docket identifiers; the Darling 58-to-Darling 54 correction and 2016 labeling error; the same-transgene and same-background explanation; the public-comment stages and counts; termination of EIS work; the PPRA-centered plant-pest review; the comparative risk finding; and the August 28 nonregulated status.
MyMap derives the identity-reconciliation lane, the separation between comment totals and posted records, and the four-state evidence flow: applicant record, corrected identity, agency plant-pest review, and regulatory effect. Those joins show why the final label cannot be read correctly from the last notice alone.
The sources leave unknown site-specific planting decisions; the scale and timing of any distribution; long-term blight, gene-flow, ecosystem, and restoration outcomes; how other authorities or land managers will act; and whether later evidence will change risk management outside this completed APHIS status decision.
Reproducible mapping method and next step
Create a versioned evidence table with one row for every petition, assessment, notice, and decision. Store the submitted event name, tested identity, correction reason, document date, publication date, observation time, review scope, and status. Keep comments received and posted comment IDs in separate numeric fields. Never overwrite the original Darling 58 label; connect it to the corrected Darling 54 record with a dated identity-reconciliation edge.
For conclusions, require three labels: source confirms, analysis derives, or unknown. Attach the comparative phrase unlikely to pose a greater plant pest risk than the nonmodified comparator to the final decision edge. Do not shorten it to safe or expand nonregulated under 7 CFR part 340 into unregulated everywhere.
The practical next step for anyone evaluating a planting or restoration proposal is to start from the August 28 status, then open a new site-specific record for the land manager, applicable authorities, ecological goals, monitoring plan, and unresolved evidence. This map explains the federal source record; it is not ecological, planting, or legal advice.
References
The controlling record includes APHIS's August 27 program update, the August 28 Federal Register notice, SUNY-ESF's amended Darling 54 petition, and APHIS's explanation of the petition-review boundary. Accessed August 30, 2026.
Cite this article
Chen, Maya. “Darling 54 is deregulated, not declared risk-free.” MyMap Research, August 30, 2026. https://www.mymap.ai/blog/darling-54-deregulation-evidence-map