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| Crop | Growth Stage to Sample | Plant Part to Sample* | Number to Sample |
| Barley (Hordeum vulgare, Crop File 1.03.153) | |||
| A. Emergence to tillering (Feekes 1 to 4) | Whole plant | 30 - 40 | |
| B. Stem extension, jointing (Feekes 5 to 7) | Whole tillers | 30 - 40 | |
| C. Pre-boot (Feekes 8 to 9) | Whole stems | 25 - 30 | |
| D. Boot to head emergence (Feekes 10 to 10.1) | Whole stems | 30 - 40 | |
| E. Flowering (Feekes 10.5.1 to 10.5.4) | Whole stems | 25 - 30 | |
| Camilena (Camelina sativa, Crop File 1.03.200) | |||
| Mid-season | MRM leaf blade | 25 - 30 | |
| Canola (Brassica rapus, Crop File 1.03.202) | |||
| A. Rosette (2-leaf to pre-bud) | Whole plant | 15 - 20 | |
| B. Budding to early flower | MRM leaf blade | 25 - 30 | |
| C. Flowering | MRM leaf blade | 25 - 30 | |
| D. Pod formation to maturity | MRM leaf blade | 25 - 30 | |
| Corn (Zea mays, Crop File 1.03.235) | |||
| A. Emergence to 4-leaf (VE - V4) | Whole plant | 20 - 25 | |
| B. 6-leaf to 10-leaf (V6 - V10) | Youngest, mature leaves | 15 - 20 | |
| C. V12-leaf to pre-tassel (V12 - V18) | Youngest mature leaves | 15 - 20 | |
| D. Tasseling (VT) | Ear leaf | 15 - 20 | |
| E. Silking (R1) | Ear leaf | 15 - 20 | |
| F. Blister to milk (R2 - R3) | Ear leaf | 15 - 20 | |
| G. Post-season (1 to 3 weeks after 80% black layer) | Lower stalk segment | 12 - 15 | |
| Cotton (Gossypium hirsutum, Crop File 1.03.241) | |||
| Emergence to match-head square | MRM leaf blade | 25 - 30 | |
| Match-head square to first bloom | MRM leaf blade | 25 - 35 | |
| First bloom | MRM leaf blade | 25 - 35 | |
| Early flowering to peak bloom | MRM leaf blade | 25 - 35 | |
| Peak bloom to boll-fill | MRM leaf blade | 25 - 35 | |
| Boll-fill | MRM leaf blade | 25 - 35 | |
| Seasonal monitoring | Petiole of MRM leaf | 25 - 35 | |
| Grain sorghum (Sorghum bicolor, Crop File 1.03.360) | |||
| Emergence to 4-leaf | Whole plant | 15 - 20 | |
| Six-leaf to 10-leaf | Youngest mature leaves | 15 - 20 | |
| Boot stage | 3rd whole leaf from top | 15 - 20 | |
| Heading to early bloom | 3rd whole leaf from top | 15 - 20 | |
| Dough stage | 2nd whole leaf from top | 15 - 20 | |
| Guar (Cyamopsis tetragonoloba, Crop File 1.03.375) | |||
| n/a | |||
| Hops (Humulus lupulus, Crop File 1.03.405) | |||
| A. Vegetative growth to flowering: Cascade variety | Petiole | 30 - 50 | |
| B. Vegetative growth to flowering: Chinook variety | Petiole | 30 - 50 | |
| Millet, foxtail (Setaria italica, Crop File 1.03.565) | |||
| Early growth to pre-boot | Whole stems | 25 - 30 | |
| Millet, pearl (Pennisetum glaucum, Crop File 1.03.566) | |||
| Early growth to pre-boot | Whole stems | 25 - 30 | |
| Millet, proso (Panicum miliaceum, Crop File 1.03.567) | |||
| Early growth to pre-boot | Whole stems | 25 - 30 | |
| Mint (Menthus sp., Crop File 1.03.572) | |||
| Growing season | Upper stems, not including leaves | one pint | |
| Oats (Avena sativa, Crop File 1.03.655) | |||
| A. Emergence to tillering (Feekes 1 to 4) | Whole plant | 30 - 40 | |
| B. Stem extension, jointing (Feekes 5 to 7) | Whole tillers | 30 - 40 | |
| C. Pre-boot (Feekes 8 to 9) | Whole stems | 25 - 30 | |
| D. Boot to head emergence (Feekes 10 to 10.1) | Whole stems | 30 - 40 | |
| E. Flowering (Feekes 10.5.1 to 10.5.4) | Whole stems | 25 - 30 | |
| F. Grain fill to maturity | Whole stems | 25 - 30 | |
| Peanuts (Arachis hypogaea, Crop File 1.03.722) | |||
| A. Emergence to 30 days after emergence | Whole plant | 30 - 40 | |
| B. Pre-bloom to flowering | Youngest, mature leaves | 50 - 60 | |
| C. Early pegging | Youngest, mature leaves | 50 - 60 | |
| D. Pod formation to maturity | Fully-developed mature leaves | 50 - 60 | |
| Popcorn (Zea mays var. evert, Crop File 1.03.763)) | |||
| Tasseling to silking | Ear leaf | 15 - 25 | |
| Rice (Oryza sativa, Crop File 1.03.805) | |||
| A. Mid-tillering | Youngest, fully developed Y- leaves | 25 - 30 | |
| B. Maximum tillering | Youngest, fully developed Y- leaves | 25 - 30 | |
| C. Panicle initiation | Youngest, fully developed Y- leaves | 25 - 30 | |
| D. Boot stage | Flag leaf | 50 - 70 | |
| Rye (Secale cereale, Crop File 1.03.816) | |||
| Early growth to pre-boot | Whole stems | 25 - 30 | |
| Safflower (Carthamus tinctorius, Crop File 1.03.825) | |||
| Mid-season | Youngest mature leaf from top | 30 - 40 | |
| Soybeans (Glycine max, Crop File 1.03.840) | |||
| Emergence to third trifoliate (growth stage VC to V3) | Whole plant | 20 - 30 | |
| Fourth trifoliate to first flower (growth stage V4 to R1) | Youngest, fully mature trifoliate | 15 - 20 | |
| Flowering to early pod fill (growth stage R2 to R4) | Youngest, fully mature trifoliate | 15 - 20 | |
| Sugarbeet (Beta vulgaris, Crop File 1.03.862) | |||
| Midseason | Youngest mature leaf | 20 - 25 | |
| Sugarcane (Saccharum officinarum, Crop File 1.03.865) | |||
| "Grand growth" period | Uppermost leaf blade | 15 - 20 | |
| Sunflower (Helianthus annus, Crop File 1.03.870) | |||
| A. Emergence to 4 true leaves | Fully developed leaves | 25 - 30 | |
| B. 8 true leaves to bud stage | Youngest, fully mature leaves | 25 - 30 | |
| C. Flowering | Youngest, fully mature leaves | 25 - 30 | |
| Tobacco (Nicotiana tabacum, Crop File 1.03.915) | |||
| A. Seedling to early growth (30 to 45 days after planting) | Whole plant or leaves | 12 - 15 | |
| B. Early growth (45 to 60 days after planting) | MRM fully-developed leaf. | 12 - 15 | |
| C. Bloom or flowering (60 to 80 days after planting) | MRM fully-developed leaf. | 10 - 15 | |
| D. Maturity (80 to 100 days after planting, flue-cured) | MRM fully-developed leaf. | 10 - 15 | |
| E. Maturity (80 to 100 days after planting, air-cured burley) | MRM fully-developed leaf. | 10 - 15 | |
| F. Harvest, flue-cured | Leaves | 10 - 15 | |
| Triticale (Triticosecale Crop File 1.03.935) | |||
| A. Emergence to tillering (Feekes 1 to 4) | Whole plant | 30 - 40 | |
| B. Stem extension, jointing (Feekes 5 to 7) | Whole tillers | 30 - 40 | |
| C. Pre-boot (Feekes 8 to 9) | Whole stems | 25 - 30 | |
| D. Boot to head emergence (Feekes 10 to 10.1) | Whole stems | 25 - 30 | |
| E. Flowering (Feekes 10.5.1 to 10.5.4) | Whole stems | 25 - 30 | |
| Wheat, durum (Triticum durum, Crop File 1.03.970) | |||
| Boot to head emergence (Feekes stage 10 to 10.1) | Whole stems | 25 - 30 | |
| Wheat (Triticum aestivum, Crop File 1.03.972) | |||
| A. Emergence to tillering (Feekes 1 to 4) | Whole plant | 30 - 40 | |
| B. Stem extension, jointing (Feekes 5 to 7) | Whole tillers | 30 - 40 | |
| C. Pre-boot (Feekes 8 to 9) | Whole stems | 25 - 30 | |
| Dw. Boot to head emergence (Feekes 10 to 10.1) | Whole stems or | 25 - 30 | |
| Df. Boot to head emergence (Feekes 10 to 10.1) | Flag leaf | 50 - 70 | |
| Ew. Flowering (Feekes 10.5.1 to 10.5.4) | Whole stems or | 25 - 30 | |
| Ef. Flowering (Feekes 10.5.1 to 10.5.4) | Flag leaf | 50 - 70 | |
| Fw. Dough (Feekes 11.2) | Whole stems or | 25 -30 | |
| Ff. Dough (Feekes 11.2) | Flag leaf | 50 -70 | |