Section 180.547 - Prohexadione calcium; tolerances for residues(a)General. Tolerances are established for residues of the growth regulator, prohexadione calcium, including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels specified below is to be determined by measuring only prohexadione calcium (calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate)" in or on the following commodities. | Commodity | Parts per
million |
| Cattle, kidney | 0.10 |
| Cattle, meat byproducts, except kidney | 0.05 |
| Cherry, sweet | 0.40 |
| Fruit, pome, group 11 | 3.0 |
| Goat, kidney | 0.10 |
| Goat, meat byproducts, except kidney | 0.05 |
| Grass, forage1 | 0.10 |
| Grass, hay1 | 0.10 |
| Grass, seed screenings1 | 3.5 |
| Grass, straw1 | 1.2 |
| Hog, kidney | 0.10 |
| Hog, meat byproducts, except kidney | 0.05 |
| Horse, kidney | 0.10 |
| Horse, meat byproducts, except kidney | 0.05 |
| Peanut | 1.0 |
| Peanut, hay | 0.60 |
| Sheep, kidney | 0.10 |
| Sheep, meat byproducts, except kidney | 0.05 |
| Strawberry | 0.30 |
| Watercress | 4.0 |
1Registration is limited to grass grown for seed.
(b)Section 18 emergency exemptions. [Reserved](c)Tolerances with regional registrations. Tolerances with regional registration are established for residues of the plant growth regulator, prohexadione calcium, including its metabolites and degradates, in or on the commodities in table 2 in this paragraph (c). Compliance with the tolerance levels specified in table 2 in this paragraph (c) is to be determined by measuring only prohexadione calcium (calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate) in or on the following commodities. Table 2 to Paragraph (c)
| Commodity | Parts per
million |
| Alfalfa, forage | 0.1 |
| Alfalfa, hay | 0.1 |
| Corn, field, forage | 0.1 |
| Corn, field, grain | 0.1 |
| Corn, field, stover | 0.1 |
(d)Indirect or inadvertent residues. [Reserved] 65 FR 25660 , May 3, 2000, as amended at 66 FR 29712 , June 1, 2001; 76 FR 71464 , Nov. 18, 2011; 80 FR 38980 , July 8, 2015; 85 FR 8461 , Feb. 14, 2020