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| Crop | Growth Stage to Sample | Plant Part to Sample* | Number to Sample |
| Alfalfa (Medicago sativa, Crop File 1.03.120) | |||
| A. Vegetative stage (early growth to pre-bud) | Whole stems | 25 - 30 | |
| B. Bud to 1/10th bloom (early bloom) | Whole stems | 25 - 35 | |
| C. Bud to 1/10th bloom (early bloom) | Top 6-inches | 30 - 40 | |
| D. Full-bloom or late-bloom stage | Whole stems | 25 - 35 | |
| Bahiagrass (Paspalum notatum, Crop File 1.03.151) | |||
| Mid-growth | Whole stems | 25 - 35 | |
| Bermudagrass (Cynodon dactylon, Crop File 1.03.170) | |||
| Early growth | Whole plant | 30 - 40 | |
| Mid-growth | Whole plant | 25 - 35 | |
| Bluegrass (Poa pratensis, Crop File 1.03.180) | |||
| Mid-growth | Whole stems | 25 - 35 | |
| Bluestem (Andropogon species., Crop File 1.03.183 | |||
| Early growth | Whole stems | 25 - 35 | |
| Bromegrass, smooth (Bromus inermis, Crop File 1.03.189) | |||
| Early growth | Whole stems | 25 - 35 | |
| Clovers: (Trifolium species, Crop File 1.03.225) | |||
| A. alsike (Trifolium hybridum) | |||
| First flower | Whole plants | 20 - 25 | |
| B. red (Trifolium pratense) | |||
| Before bloom | Whole plants | 20 - 25 | |
| C. white/ladino (Trifolium repens) | |||
| Before bloom | Whole plants | 20 - 25 | |
| Cowpea (Vigna unguiculata, Crop File 1.03.245) | |||
| Early bloom | Youngest, fully-developed leaves | 15 - 20 | |
| Fescue, tall (Festuca arundinacea, Crop File 1.03.290) | |||
| Early growth | Whole plant | 25 - 35 | |
| Miscanthus (Miscanthus gigantheus, Crop File 1.03.575) | |||
| Early to mid-growth | Whole plants | 15 - 25 | |
| Orchardgrass (Dactylis glomerata, Crop File 1.03.685) | |||
| Early growth | Whole plant | 25 - 35 | |
| Peas, field/forage/winter (Pisum sativum, Crop File 1.03.727) | |||
| Bloom or "flat-pod" stage | Whole plant | 15 - 20 | |
| Sanfoin (Onobrychis viciifolia, Crop File 1.03.833) | |||
| Active growth | Whole plant | 15 - 20 | |
| Sudangrass (Sorghum bicolor, Sorghum sudanense, Crop File 1.03.860) | |||
| A. Emergence to 12-inches tall | Whole plant | 15 - 20 | |
| B. Over 12-inches tall | Whole plant | 15 - 20 | |
| Switchgrass (Panicum virgatum, Crop File 1.03.885) | |||
| Heading | Whole plant | 25 - 35 | |
| Trefoil, birdsfoot (Lotus corniculatus, Crop File 1.03.930) | |||
| First flower | Mature leaves | 25 - 35 | |