Section 201.51 - Inert matterInert matter shall include seeds and seed-like structures from both crop and weed plants and other material not seeds as follows:
(a) Seeds and seed-like structures from crop plants:(1) Seeds of legumes (Fabaceae) and brassica (Brassicaceae) with the seed coats entirely removed. Refer to § 210.48(a) for pure seed classification.(2) Pieces of broken and damaged seed units, including those that are insect damaged, which are one-half the original size or less. If greater than one-half, refer to § 201.48(b) and (c) for pure seed classification. Also included as inert matter are separated cotyledons of legumes, irrespective of whether or not the radicle-plumule axis and/or more than one-half of the seed coat may be attached.(3) Chalcid-damaged seeds (puffy, soft, or dry and crumbly) of alfalfa, red clover, crimson clover, and similar kinds of small seeded legumes. Refer to § 201.48(c) for pure seed classification.(4) Glumes and empty florets except as stated under pure seed. Refer to § 201.48(g) and (h) for pure seed classification.(5) Seed units with nematode galls or fungal bodies (smut, ergot, and other sclerotia) that are not entirely enclosed within the seed unit. Refer to § 201.48(h) for pure seed classification.(6) Broken seed units of Chenopodiaceae and fruit portions or fragments of monogerm beets, New Zealand spinach, buffalograss, and families in which the seed unit is a dry indehiscent one-seeded fruit that visibly do not contain a seed. Refer to § 201.48(f), (g)(1), (i) , and (j) for pure seed classification.(7) Seed units of forage kochia that pass through a 1 mm opening, square-hole sieve, when shaken for 30 seconds.(8) The thin pericarp (fruit wall), if present on seeds of northern sweetvetch.(9) Immature florets of smooth brome, fairway crested wheatgrass, standard crested wheatgrass, tall wheatgrass, intermediate wheatgrass, pubescent wheatgrass, western wheatgrass, fescues (Festuca spp.), and ryegrasses (Lolium spp.) in which the caryopses are less than one-third the length of the palea; the caryopsis is measured from the base of the rachilla.(b) Seeds and seed-like structures from weed plants, which by visual examination (including the use of light or dissection), can be determined to be within the following categories:(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 grass caryopses, including free caryopses, with over one-half the root-shoot axis missing (the scutellum excluded);(iii) Immature free caryopses devoid of embryo and/or endosperm;(iv) Immature florets of quackgrass (Elymus 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;(v) Free caryopses of quackgrass (E. repens) that are 2 mm or less in length.(3) Seeds of legumes and species of Brassica 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: Sedge (Cyperaceae), buckwheat (Polygonaceae), morning glory (Convolvulaceae), nightshade (Solanaceae), puncturevine (Zygophyllaceae) and sunflower (Asteraceae). Cocklebur (Xanthium spp.) burs are to be dissected to determine whether or not seeds are present.(5) Wild onion and wild garlic (Allium spp.) bulblets:(i) Bulblets which are completely devoid of the husk and pass through a1/13th-inch, round-hole sieve.
(ii) Bulblets which show evident damage to the basal end, whether husk is present or absent. Refer to § 201.50(c) for wild onion and wild garlic (Allium spp.) bulblets classed as weed seeds.(6) Dodder (Cuscuta spp.): Seeds devoid of embryos and seeds which are ashy gray to creamy white in color are inert matter. Seeds should be sectioned when necessary to determine if an embryo is present as when seeds have a normal color but are slightly swollen, dimpled or have minute holes.(7) Buckhorn (Plantago lanceolata): Black seeds, with no brown color evident, whether shriveled or plump; the color of questionable seeds shall be determined by use of a stereoscopic microscope with magnification of approximately 10 * and a fluorescent lamp with two 15-watt daylight-type tubes.(8) Ragweed (Ambrosia spp.): Seed with both the involucre and pericarp absent.(c) Other matter that is not seed:(1) Free nematode galls or fungal bodies such as smut, ergot, and other sclerotia.(2) Soil particles, sand, stone, chaff, stems, leaves, flowers, loose coating material, and any other foreign material.(3) Coating material removed from coated seed by washing. Refer to § 201.51b(c) .46 FR 53637, Oct. 29, 1981; 46 FR 58059, Nov. 30, 1981, as amended at 59 FR 64498, Dec. 14, 1994; 65 FR 1707 , Jan. 11, 2000; 76 FR 31794 , June 2, 2011; 85 FR 40581 , July 7, 2020