§ 201.46 - Weight of working sample.  


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  • § 201.46 Weight of working sample.

    (a) Unmixed seed. The working samples for purity analysis and noxiousweed seed examination of unmixed seed shall be at least the weights set forth in table 1.

    (b) Mixtures consisting of one predominant kind of seed or groups of kinds of similar size. The weights of the purity and noxious-weed seed working samples in this category shall be determined by the kind or group of kinds which comprise more than 50 percent of the sample.

    (c) Mixtures consisting of two or more kinds or groups of kinds of different sizes, none of which comprise over 50 percent of the sample. The weights of the purity working samples in this category shall be the weighted averages (to the nearest half gram) of the weights listed in table 1 for each of the kinds which comprise the sample determined by the following method:

    (1) Multiply the percentage of each component in the mixture (rounded off to the nearest whole number) by the sample sizes specified in column 2, table 1,

    (2) add all these products,

    (3) total the percentages of all components of the mixtures, and

    (4) divide the sum in paragraph (c)(2) of this section by the total in paragraph (c)(3) of this section. If the approximate percentage of the components of a mixture are not known they may be estimated. The weight of the noxious-weed seed working sample shall be determined by multiplying the weight of the purity working sample by 10 or by calculating the weighted average in the same manner described above for the purity working sample.

    (d) Coated seed.

    (1) Unmixed coated seed. Due to variation in the weight of coating materials, the size or weight of the working sample shall be determined separately for each lot. The weight of the working sample shall be determined by weighing 100 completely coated units and calculating the weight of 2,500 coated units for the purity analysis and 25,000 coated units for the noxious-weed seed examination.

    (2) Mixtures of coated seed. The working weight shall be determined in the following manner:

    (i) Calculate the weight of the working sample to be used for the mixture under consideration as though the sample were not coated by following paragraph (b) or (c) of this section.

    (ii) Determine the amount of coating material on 100 coated units by weighing the coated units. Remove the coating material using the methods described in §§ 201.51b (c) and (d). Calculate the percentage of coating material using the following formulas:

    Weight of coating material = weight of 100 coated units − weight of 100 de-coated units;

    The percentage of coating material = weight of the coating material divided by the weight of 100 coated units × 100%.

    (iii) The weight of the working sample shall be the product of the weight calculated in paragraph (d)(2)(i) of this section multiplied by 100 percent, divided by 100 percent minus the percentage of coating material calculated in paragraph (d)(2)(ii) of this section.

    Table 1 - Weight of Working Sample

    Name of seed Minimum weight for purity analysis (grams) Minimum weight for noxious-weed seed examination (grams) Approximate number of seeds per gram
    Agricultural Seed
    Agrotricum6550039
    Alfalfa550500
    Alfilaria550440
    Alyceclover550665
    Bahiagrass:
    Var. Pensacola550600
    All other vars.750365
    Barley10050030
    Barrelclover10100250
    Bean:
    Adzuki20050011
    Field5005004
    Mung10050024
    Beet, field5050055
    Beet, sugar5050055
    Beggarweed, Florida550440
    Bentgrass:
    Colonial0.252.513,000
    Creeping0.252.513,515
    Velvet0.252.518,180
    Bermudagrass1103,930
    Bermudagrass, giant1102,950
    Bluegrass:
    Annual1102,635
    Bulbous440585
    Canada0.555,050
    Glaucantha110
    Kentucky1103,060
    Nevada1102,305
    Rough0.554,610
    Texas1102,500
    Wood0.554,330
    Bluejoint0.558,461
    Bluestem:
    Big770320
    Little550525
    Sand10100215
    Yellow1101,945
    Bottlebrush-squirreltail990300
    Brome:
    Field550465
    Meadow13130190
    Mountain20200140
    Smooth770315
    Broomcorn4040060
    Buckwheat5050045
    Buffalograss:
    (Burs)20200110
    (Caryopses)330740
    Buffelgrass:
    (Fascicles)666365
    (Caryopses)2201,940
    Burclover, California:
    (in bur)50500
    (out of bur)770375
    Burclover, spotted
    (in bur)5050050
    (out of bur)550550
    Burnet, little25250110
    Buttonclover770365
    Camelina440880
    Canarygrass20200150
    Canarygrass, reed2201,185
    Camelina440880
    Carpetgrass1102,230
    Castorbean5005005
    Chess, soft550555
    Chickpea5005002
    Clover:
    Alsike2201,500
    Arrowleaf440705
    Berseem550455
    Cluster1102,925
    Crimson10100330
    Kenya220
    Ladino2201,935
    Lappa2201,500
    Large hop1105,435
    Persian2201,415
    Red550600
    Rose770360
    Small hop2201,950
    Strawberry550635
    Sub25250120
    White2201,500
    Corn:
    Field5005003
    Pop5005003
    Cotton3005008
    Cowpea3005008
    Crambe25250
    Crested dogtail2201,900
    Crotalaria:
    Lance770375
    Showy2525080
    Slenderleaf10100205
    Striped10100215
    Sunn7550035
    Crownvetch10100305
    Dallisgrass440620
    Dichondra550470
    Dropseed, sand0.252.512,345
    Emmer10050025
    Fescue:
    Chewings330900
    Hair110
    Hard2201,305
    Meadow550495
    Red330900
    Sheep2201,165
    Tall550455
    Flatpea10050025
    Flax15150180
    Foxtail, creeping1.5151,736
    Foxtail, meadow330893
    Galletagrass:
    (Other than caryopses)10100260
    (Caryopses)550580
    Grama:
    Blue2201,595
    Side-oats:
    (Other than caryopses)660350
    (Caryopses)2201,605
    Guar7550035
    Guineagrass2202,205
    Hardinggrass330750
    Hemp5050045
    Indiangrass, yellow770395
    Indigo, hairy770435
    Japanese lawngrass2201,325
    Johnsongrass10100265
    Kenaf50500
    Kochia, forage2201,070
    Kudzu2525080
    Lentil12050014-23
    Lespedeza:
    Korean550525
    Sericea330820
    Siberian330820
    Striate550750
    Lovegrass, sand1103,585
    Lovegrass, weeping1103,270
    Lupine:
    Blue5005007
    White5005007
    Yellow3005009
    Manilagrass220
    Medic, black550585
    Milkvetch990270
    Millet:
    Browntop880315
    Foxtail550480
    Japanese990315
    Pearl15150180
    Proso15150185
    Molassesgrass0.557,750
    Mustard:
    Black2201,255
    India550625
    White15150160
    Napiergrass550
    Needlegrass, green770370
    Oat7550035-50
    Oatgrass, tall660417
    Orchardgrass330945
    Panicgrass, blue2201,370
    Panicgrass, green2201,305
    Pea, field5005004
    Peanut5005001-3
    Radish3030075
    Rape:
    Annual770345
    Bird770425
    Turnip550535
    Winter10100230
    Redtop0.252.510,695
    Rescuegrass20200115
    Rhodesgrass1104,725
    Rice5050065
    Ricegrass, Indian770355
    Roughpea7550040
    Rye7550040
    Rye, mountain2828090
    Ryegrass:
    Annual550420
    Intermediate880338
    Perennial550530
    Wimmera550
    Safflower10050030
    Sagewort, Louisiana0.558,900
    Sainfoin5050050
    Saltbush, fourwing15150165
    Sesame770360
    Sesbania25250105
    Smilo2202,010
    Sorghum5050055
    Sorghum almum15150150
    Sorghum-sudangrass6550038
    Sorgrass1 15150135
    Sourclover550660
    Soybean5005006-13
    Spelt10050025
    Sudangrass25250100
    Sunflower100500
    Sweetclover:
    White550570
    Yellow550570
    Sweet vernalgrass2201,600
    Sweetvetch, northern19190130
    Switchgrass440570
    Teff1103,288
    Timothy1102,565
    Timothy, turf1102,565
    Tobacco0.5515,625
    Trefoil:
    Big2201,945
    Birdsfoot330815
    Triticale100500
    Vaseygrass330970
    Veldtgrass440655
    Velvetbean5005002
    Velvetgrass1103,360
    Vetch:
    Common15050019
    Hairy7550035
    Hungarian10050024
    Monantha100500
    Narrowleaf5050060
    Purple10050022
    Woollypod10050025
    Wheat:
    Common10050025
    Club10050025
    Durum10050025
    Polish10050025
    Poulard10050025
    Wheat × Agrotricum6550038
    Wheatgrass:
    Beardless880275
    Fairway crested440685
    Standard crested550425
    Intermediate15150175
    Pubescent15150180
    Siberian550
    Slender770295
    Streambank1050370
    Tall15150165
    Western10100250
    Wildrye:
    Basin880317
    Canada11110190
    Russian660360
    Vegetable Seed
    Artichoke10050024
    Asparagus10050025
    Asparagusbean3005008
    Bean:
    Garden5005004
    Lima5005002
    Runner5005001
    Beet5030060
    Broadbean500500
    Broccoli1050315
    Brussels sprouts1050315
    Burdock, great15150
    Cabbage1050315
    Cabbage, Chinese550635
    Cabbage, tronchuda10100
    Cardoon100500
    Carrot350825
    Cauliflower1050315
    Celeriac1252,520
    Celery1252,520
    Chard, Swiss5030060
    Chicory350940
    Chives550
    Citron20050011
    Collards1050315
    Corn, sweet500500
    Cornsalad:
    Vars. Fullhearted and Dark Green Fullhearted550
    All other vars1050380
    Cowpea3005008
    Cress:
    Garden550425
    Upland2351,160
    Water1255,170
    Cucumber7550040
    Dandelion2351,240
    Dill350800
    Eggplant1050230
    Endive350940
    Gherkin, West India16160153
    Kale1050315
    Kale, Chinese1050
    Kale, Siberian880325
    Kohlrabi1050315
    Leek750395
    Lettuce350890
    Melon5050045
    Mustard, India550625
    Mustard, spinach550535
    Okra10050019
    Onion750340
    Onion, Welsh1050
    Pak-choi550635
    Parsley550650
    Parsnip550430
    Pea5005003
    Pepper15150165
    Pumpkin5005005
    Radish3030075
    Rhubarb5030060
    Rutabaga550430
    Sage25150120
    Salsify5030065
    Savory, summer2351,750
    Sorrel2351,080
    Soybean5005006-13
    Spinach25150100
    Spinach, New Zealand20050013
    Squash20050014
    Tomato550405
    Tomato, husk2351,240
    Turnip550535
    Watermelon20050011

    [25 FR 8769, Sept. 13, 1960, as amended at 30 FR 7888, June 18, 1965; 32 FR 12780, Sept. 6, 1967; 35 FR 6108, Apr. 15, 1970; 41 FR 20156, May 17, 1976; 46 FR 53635, Oct. 29, 1981; 59 FR 64492, Dec. 14, 1994; 65 FR 1707, Jan. 11, 2000; 85 FR 40580, July 7, 2020]