(a) Seeds of the plants listed in paragraphs (a)(1) and (a)(2) of this section shall be considered noxious weed seeds.
(1) Seeds with no tolerances applicable to their introduction:
Acacia nilotica (Linnaeus) Wildenow ex Delile
Aeginetia spp.
Ageratina adenophora (Sprengel) King & Robinson
Ageratina riparia (Regel) R.M. King and H. Robinson
Alectra spp.
Alternanthera sessilis (L.) R. Brown ex de Candolle
Arctotheca calendula (Linnaeus) Levyns
Asphodelus fistulosus L.
Avena sterilis L. (including Avena ludoviciana Durieu)
Azolla pinnata R. Brown
Carthamus oxyacantha M. Bieberstein
Chrysopogon aciculatus (Retzius) Trinius
Commelina benghalensis L.
Crupina vulgaris Cassini
Cuscuta spp.
Digitaria abyssinica (Hochstetter ex A. Richard) Stapf
Digitaria velutina (Forsskal) Palisot de Beauvois
Drymaria arenariodes Humboldt & Bonpland ex J.A. Schultes
Eichhornia azurea (Swartz) Kunth
Emex australis Steinheil
Emex spinosa (L.) Campdera
Euphorbia terracina Linnaeus
Galega officinalis L.
Heracleum mantegazzianum Sommier & Levier
Hydrilla verticillata (Linnaeus f.) Royle
Hygrophila polysperma T. Anderson
Imperata brasiliensis Trinius
Imperata cylindrica (Linnaeus) Palisot de Beauvois
Inula britannica Linnaeus
Ipomoea aquatica Forsskal
Ischaemum rugosum Salisbury
Lagarosiphon major (Ridley) Moss
Leptochloa chinensis (L.) Nees
Limnophila sessiliflora (Vahl) Blume
Lycium ferocissimum Miers
Lygodium flexuosum (Linnaeus) Swartz (maidenhair creeper)
Lygodium microphyllum (Cavanilles) R. Brown (Old World climbing fern)
Melaleuca quinquenervia (Cav.) Blake
Melastoma malabathricum L.
Mikania cordata (Burman f.) B. L. Robinson
Mikania micrantha Kunth
Mimosa diplotricha C. Wright
Mimosa pigra L. var. pigra
Monochoria hastata (L.) Solms-Laubach
Monochoria vaginalis (Burman f.) C. Presl
Moraea collina Thunberg
Moraea flaccida (Sweet) Steudel
Moraea miniata Andrews
Moraea ochroleuca (Salisbury) Drapiez
Moraea pallida (Baker) Goldblatt
Nassella trichotoma (Nees) Hackel ex Arechavaleta
Onopordum acaulon Linnaeus
Onopordum illyricum Linnaeus
Opuntia aurantiaca Lindley
Orobanche spp.
Oryza longistaminata A. Chevalier & Roehrich
Oryza punctata Kotschy ex Steudel
Oryza rufipogon Griffith
Ottelia alismoides (L.) Pers.
Paspalum scrobiculatum L.
Pennisetum clandestinum Hochstetter ex Chiovenda
Pennisetum macrourum Trinius
Pennisetum pedicellatum Trinius
Pennisetum polystachion (L.) Schultes
Prosopis alapataco R. A. Philippi
Prosopis argentina Burkart
Prosopis articulata S. Watson
Prosopis burkartii Munoz
Prosopis caldenia Burkart
Prosopis calingastana Burkart
Prosopis campestris Grisebach
Prosopis castellanosii Burkart
Prosopis denudans Bentham
Prosopis elata (Burkart) Burkart
Prosopis farcta (Banks & Solander) J.F. Macbride
Prosopis ferox Grisebach
Prosopis fiebrigii Harms
Prosopis hassleri Harms
Prosopis humilis Gillies ex Hooker & Arnott
Prosopis kuntzei Harms
Prosopis pallida (Humboldt & Bonpland ex Willdenow) Kunth
Prosopis palmeri S. Watson
Prosopis reptans Bentham var. reptans
Prosopis rojasiana Burkart
Prosopis ruizlealii Burkart
Prosopis ruscifolia Grisebach
Prosopis sericantha Gillies ex Hooker & Arnott
Prosopis strombulifera (Lamarck) Bentham
Prosopis torquata (Cavanilles ex Lagasca y Segura) de Candolle
Rottboellia cochinchinensis (Lour.) W. Clayon
Rubus fruticosus L. (complex)
Rubus moluccanus L.
Saccharum spontaneum L.
Sagittaria sagittifolia L.
Salsola vermiculata L.
Salvinia auriculata Aublet
Salvinia biloba Raddi
Salvinia herzogii de la Sota
Salvinia molesta D.S. Mitchell
Senecio inaequidens DC.
Senecio madagascariensis Poir.
Setaria pumila (Poir.) Roem. & Schult. subsp. pallidefusca (Schumach.) B.K. Simon
Solanum tampicense Dunal (wetland nightshade)
Solanum torvum Swartz
Solanum viarum Dunal
Sparganium erectum L.
Spermacoce alata Aublet
Striga spp.
Tridax procumbens L.
Urochloa panicoides Beauvois
(2) Seeds with tolerances applicable to their introduction:
Acroptilon repens (L.) DC. (=Centaurea repens L.) (=Centaurea picris)
Cardaria draba (L.) Desv.
Cardaria pubescens (C. A. Mey.) Jarmol.
Convolvulus arvensis L.
Cirsium arvense (L.) Scop.
Elytrigia repens (L.) Desv. (=Agropyron repens (L.) Beauv.)
Euphorbia esula L.
Sonchus arvensis L.
Sorghum halepense (L.) Pers.
(b) The tolerance applicable to the prohibition of the noxious weed seeds listed in paragraph (a)(2) of this section shall be two seeds in the minimum amount required to be examined as shown in column 1 of table 1 of § 361.5. If fewer than two seeds are found in an initial examination, the shipment from which the sample was drawn may be entered. If two seeds are found in an initial examination, a second sample must be examined. If two or fewer seeds are found in the second examination, the shipment from which the samples were drawn may be entered. If three or more seeds are found in the second examination, the shipment from which the samples were drawn may not be entered. If three or more seeds are found in an initial examination, the shipment from which the sample was drawn may not be entered.
(c) Any seed of any noxious weed that can be determined by visual inspection (including the use of transmitted light or dissection) to be within one of the following categories shall be considered inert matter and not counted as a weed seed:
(1) Damaged seed (other than grasses) with over one half of the embryo missing;
(2) Grass florets and caryopses classed as inert:
(i) Glumes and empty florets of weedy grasses;
(ii) Damaged caryopses, including free caryopses, with over one-half the root-shoot axis missing (the scutellum excluded);
(iii) Immature free caryopses devoid of embryo or endosperm;
(iv) Free caryopses of quackgrass (Elytrigia repens) that are 2 mm or less in length; or
(v) Immature florets of quackgrass (Elytrigia repens) in which the caryopses are less than one-third the length of the palea. The caryopsis is measured from the base of the rachilla.
(3) Seeds of legumes (Fabaceae) with the seed coats entirely removed.
(4) Immature seed units, devoid of both embryo and endosperm, such as occur in (but not limited to) the following plant families: buckwheat (Polygonaceae), morning glory (Convolvulaceae), nightshade (Solanaceae), and sunflower (Asteraceae).
(5) Dodder (Cuscuta spp.) seeds devoid of embryos and seeds that are ashy gray to creamy white in color are inert matter. Dodder seeds should be sectioned when necessary to determine if an embryo is present, as when the seeds have a normal color but are slightly swollen, dimpled, or have minute holes.
[62 FR 48460, Sept. 16, 1997, as amended at 64 FR 12884, Mar. 16, 1999; 65 FR 33743, May 25, 2000; 71 FR 35381, June 20, 2006; 74 FR 53400, Oct. 19, 2009; 75 FR 68956, Nov. 10, 2010]