This regulation establishes a tolerance for combined residues of prothioconzole and prothioconazole-desthio, calculated as parent, in or on soybean, forage; soybean, seed; soybean, hay; and sugar beet, roots. Bayer CropScience requested this tolerance under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA).