Section 180.662 - Trinexapac-ethyl; tolerances for residues(a)General. Tolerances are established for residues of the plant growth regulator, trinexapac-ethyl, including its metabolites and degradates, in or on the commodities in table 1 to this paragraph (a). Compliance with the tolerance levels specified in table 1 is to be determined by measuring only the free and conjugated forms of both trinexapac-ethyl, ethyl 4-(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylate and trinexapac, 4-(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylic acid, calculated as the stoichiometric equivalent of trinexapac-ethyl, in or on the commodity. Table 1 to Paragraph (a)
| Commodity | Parts per
million |
| Barley, bran | 2.5 |
| Barley, grain | 2.0 |
| Barley, hay | 0.8 |
| Barley, straw | 0.4 |
| Cattle, fat | 0.03 |
| Cattle, meat | 0.03 |
| Cattle, meat byproducts | 0.1 |
| Egg | 0.01 |
| Goat, fat | 0.03 |
| Goat, meat | 0.03 |
| Goat, meat byproducts | 0.1 |
| Grass, forage | 1.5 |
| Grass, hay | 4.0 |
| Grass, seed screenings | 40.0 |
| Grass, straw | 10.0 |
| Hog, fat | 0.02 |
| Hog, meat | 0.02 |
| Hog, meat by-products | 0.1 |
| Horse, fat | 0.02 |
| Horse, meat | 0.03 |
| Horse, meat byproducts | 0.04 |
| Milk | 0.01 |
| Oat, forage | 1.0 |
| Oat, grain | 4.0 |
| Oat, hay | 1.5 |
| Oat, straw | 0.9 |
| Poppy, seed1 | 8 |
| Poultry, fat | 0.01 |
| Poultry, meat | 0.01 |
| Poultry, meat byproducts | 0.1 |
| Rice, bran | 1.5 |
| Rice, grain | 0.4 |
| Rice, straw | 0.07 |
| Rice, wild, grain | 0.4 |
| Rye, bran | 6.0 |
| Rye, grain | 4.0 |
| Rye, hay | 1.5 |
| Rye, straw | 0.9 |
| Sheep, fat | 0.03 |
| Sheep, meat | 0.03 |
| Sheep, meat byproducts | 0.1 |
| Sugarcane, cane | 1.5 |
| Sugarcane, molasses | 5 |
| Wheat, bran | 6.0 |
| Wheat, forage | 1.0 |
| Wheat, grain | 4.0 |
| Wheat, hay | 1.5 |
| Wheat, middlings | 10.5 |
| Wheat, straw | 0.9 |
1 There are no U.S. registrations for Poppy, seed as of March 15, 2018.
(c)Tolerances with regional registrations. Tolerances with regional registrations, as defined in § 180.1 , are established for residues of trinexapac-ethyl, including its metabolites and degradates, in or on the commodities in table 2 to this paragraph (c). Compliance with the tolerance levels specified in table 2 is to be determined by measuring only the free and conjugated forms of both trinexapac-ethyl, ethyl 4-(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylate and trinexapac, 4-(cyclopropylhydroxymethylene)-3,5-dioxocyclohexanecarboxylic acid, calculated as the stoichiometric equivalent of trinexapac-ethyl, in or on the commodity. Table 2 to Paragraph (c)
| Commodity | Parts per
million |
| Clover, forage | 8 |
| Clover, hay | 15 |
88 FR 18434 , Mar. 29, 2023 83 FR 11422, 3/15/2018; 85 FR 70064, 11/4/2020; 88 FR 18434, 3/29/2023