(a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this section, the names of the kinds of noxious-weed seeds and the rate of occurrence of each shall be expressed in the label in accordance with, and the rate of occurrence shall not exceed the rate permitted by, the law and regulations of the state into which the seed is offered for transportation or is transported. If in the course of such transportation, or thereafter, the seed is diverted to another State of destination, the person or persons responsible for such diversion shall cause the seed to be relabeled with respect to the noxious-weed seed content, if necessary to conform to the laws and regulations of the State into which the seed is diverted.
(b) Seeds or bulblets of the following plants shall be considered noxious-weed seeds in agricultural and vegetable seeds transported or delivered for transportation in interstate commerce (including Puerto Rico, Guam, and the District of Columbia). Agricultural or vegetable seed containing seeds or bulblets of these kinds shall not be transported or delivered for transportation in interstate commerce. Noxious-weed seeds include the following species on which no tolerance will be applied: Aeginetia spp.Ageratina adenophora (Spreng.) King and H.E. Robins.Alectra spp.Alternanthera sessilis (L.) DC.Asphodelus fistulosus L.Avena sterilis L. (including Avena ludoviciana Dur.)Azolla pinnata R. Br.Carthamus oxyacantha M. BiebChrysopogon aciculatus (Retz.) Trin.Commelina benghalensis L.Crupina vulgaris Cass.Digitaria abyssinica Stapf.(=D. scalarum (Schweinf.) Chiov.)Digitaria scalarum (Schweinfurth) ChiovendaDrymaria arenarioides Roem. and Schult.Eichornia azurea (Sw.) KunthEmex australis Steinh.Emex spinosa (L.) Campd.Galega officinalis L.Heracleum mantegazzianum Sommier & LevierHomeria spp.Hydrilla verticillata (L. f.) RoyleHygrophila polysperma T. Anders.Imperata brasiliensis Trin.Imperata cylindrica (L.) Raeusch.Ipomoea aquatica Forsk.Ischaemum rugosum Salisb.Lagarosiphon major (Ridley) MossLeptochloa chinensis (L.) NeesLimnophila sessiliflora (Vahl) BlumeLycium ferocissimum MiersMelaleuca quinquenervia (Cav.) BlakeMelastoma malabathricum L.Mikania cordata (Burm. f.) B.L. Robins.Mikania micrantha H.B.K.Mimosa invisa Mart.Mimosa pigra L. var. pigraMonochoria hastata (L.) Sloms-Laub.Monochoria vaginalis (Burm. f.) K.B. PreslNassella trichotoma (Nees) ArechavaletaOpuntia aurantiaca Lindl.Oryza longistaminata A. Cheval. and Roehr.Oryza punctata Steud.Oryza rufipogon Griff.Ottelia alismoides (L.) Pers.Paspalum scrobiculatum L.Pennisetum clandestinum Chiov.Pennisetum macrourum Trin.Pennisetum pedicellatum Trin.Pennisetum polystachion (L.) Schult.Prosopis alapataco R.A. PhilippiProsopis argentina BurkartProsopis articulata S. WatsonProsopis burkartii Munoz Prosopis caldenia BurkartProsopis calingastana BurkartProsopis campestris Griseb.Prosopis castellanosii BurkartProsopis denudans Benth.Prosopis elata (Burkart) BurkartProsopis farcta (Russell) MacbrideProsopis ferox Griseb.Prosopis fiebrigii HarmsProsopis hassleri HarmsProsopis humilis Hook. and Arn.Prosopis kuntzei HarmsProsopis pallida (Willd.) H.B.K.Prosopis palmeri S. WatsonProsopis reptans Benth. var. reptansProsopis rojasiana BurkartProsopis ruizlealii BurkartProsopis ruscifolia Griseb.Prosopis sericantha Hook. and Arn.Prosopis strombulifera (Lam.) Benth.Prosopis torquata (Lagasca) DC.Rottboellia cochinchinensis (Lour.) ClaytonRubus fruticosus L. (complex)Rubus moluccanus L.Saccharum spontaneum L.Sagittaria sagittifolia L.Salsola vermiculata L.Salvinia auriculata Aubl.Salvinia biloba RaddiSalvinia herzogii de la SotaSalvinia molesta D.S. MitchellSenecio inaequidens DC.Setaria pallide-fusca (Schumach.) Stapf and Hubb.Solanum tampicense DunalSolanum torvum Sw.Solanum viarum DunalSparaganium erectum L.Spermacoce alata (Aublet) de CandolleStriga spp.Tridax procumbens L.Urochloa panicoides Beauv. [65 FR 1706, Jan. 11, 2000, as amended at 76 FR 31794, June 2, 2011]