40 CFR § 180.549 - Diflufenzopyr; tolerances for residues.

---
identifier: "/us/cfr/t40/s180.549"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 180.549 - Diflufenzopyr; tolerances for residues."
title_number: 40
title_name: "Protection of Environment"
section_number: "180.549"
section_name: "Diflufenzopyr; tolerances for residues."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "E"
subchapter_name: "PESTICIDE PROGRAMS"
part_number: "180"
part_name: "TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321(q), 346a and 371."
regulatory_source: "36 FR 22540, Nov. 25, 1971, unless otherwise noted."
cfr_part: "180"
---


# 180.549 Diflufenzopyr; tolerances for residues.

(a) *General.* Tolerances are established for combined residues of diflufenzopyr, 2-(1-[([3,5-difluorophenylamino] carbonyl)hydrazono]ethyl)-3- pyridinecarboxylic acid, and its metabolites convertible to 8- methylpyrido[2,3-d]pyridazin-5(6H)-one, expressed as diflufenzopyr, in or on the following raw agricultural commodities:

| Commodity | Parts per million |
| --- | --- |
| Corn, field, forage | 0.05 |
| Corn, field, grain | 0.05 |
| Corn, field, stover | 0.05 |
| Corn, pop, grain | 0.05 |
| Corn, pop, stover | 0.05 |
| Corn, sweet, forage | 0.05 |
| Corn, sweet, kernel plus cob with husks removed | 0.05 |
| Corn, sweet, stover | 0.05 |
| Grass, forage | 22.0 |
| Grass, hay | 7.0 |

(b) *Section 18 emergency exemptions.* [Reserved]

(c) *Tolerances with regional registrations.* [Reserved]

(d) *Indirect or inadvertent residues.* [Reserved]

[64 FR 4308, Jan. 28, 1999, as amended at 67 FR 55338, Aug. 29, 2002; 76 FR 34886, June 15, 2011]