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( NOTE: See individual Crop Files for detailed sampling instructions and analysis interpretations.)
| Crop | Growth Stage to Sample | Plant Part to Sample* | Number to Sample |
| Beans, dry (Phaseolus vulgaris, Crop File 1.03.156) | |||
| A. Before bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| C. Full bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| D. Mid-growth to early bloom | Petiole of 4th leaf from tip | 25 - 50 | |
| Beans, greena (Phaseolus vulgaris, Crop File 1.03.157) | |||
| A. Before bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| C. Full bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| D. Mid-growth to early bloom | Petiole of 4th leaf from tip | 25 - 50 | |
| Beans, limab (Phaseolus lunatus, Crop File 1.03.158) | |||
| A. Before bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| C. Full bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| D. Mid-growth to early bloom | Petiole of 4th leaf from tip | 25 - 50 | |
| Broccoli (Brassica oleracea, italica variety; Crop File 1.03.186 | |||
| A. 4 to 6 leaves | MRM leaf w/ petiole | 20 - 25 | |
| B. 10 to 12 leaves | MRM leaf w/ petiole | 20 - 25 | |
| C. First buds | MRM leaf w/ petiole | 20 - 25 | |
| D. Heading (head development) | MRM leaf w/ petiole | 20 - 25 | |
| E. Pre-arvest | MRM leaf w/ petiole | 20 - 25 | |
| F. Seasonal monitoring | Midrib of MRM leaf | 25 - 30 | |
| Cabbage (Brassica oleracea, italica variety; Crop File 1.03.186 | |||
| A. Young plants, 2 to 6 weeks old | Whole plants | 20 - 25 | |
| B. 5 weeks after transplanting | MRM leaf | 20 - 25 | |
| C. 8 weeks after transplanting | MRM leaf | 20 - 25 | |
| D. Heads half-grown | Wrapper leaf | 15 - 20 | |
| E. Harvest | Wrapper leaf | 15 - 20 | |
| F. Heading | Midrib of MRM wrapper leaf | 25 - 30 | |
| Cantaloupec (Cucumis melo, Crop File 1.03.204) | |||
| A. Early growth (less than 12 inch vines) | 5th leaf from tip | 15 - 20 | |
| B. Flowering to early fruiting | 5th leaf from tip | 15 - 20 | |
| C. Early fruiting to harvest | 5th leaf from tip | 15 - 20 | |
| D. Flowering to early fruiting | Petiole of 6th leaf from tip | 25 - 30 | |
| Carrot Daucus carota (Crop File 1.03.206) | |||
| A. Mid-growth (60 to 80 days after seeding) | MRM leaf | 25 - 35 | |
| B. Harvest | MRM leaf | 25 - 35 | |
| Cauliflower (Brassica oleracea, botrytis variety, Crop File 1.03.208) | |||
| A. Buttoning | MRM leaf blade | 25 - 30 | |
| B. Heading | MRM leaf blade | 25 - 30 | |
| C. Seasonal monitoring | Midrib of MRM leaf | 30 - 50 | |
| Cowpeasd (Vigna unguiculata, 1.03.245) | |||
| A. Pre-bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| Cucumber (Cucumis sativa, Crop File 1.03.252) | |||
| A. Pre-bloom | MRM leaf w/o petiole | 20-25 | |
| B. Early bloom to small fruit | MRM leaf w/o petiole | 20-25 | |
| C. Early fruit to harvest | MRM leaf w/o petiole | 20-25 | |
| Honeydew melone (Cucumis melo, Crop File 1.03.400) | |||
| A. Early growth (less than 12 inch vines) | 5th leaf from tip | 15 - 20 | |
| B. Flowering to early fruiting | 5th leaf from tip | 15 - 20 | |
| C. Early fruiting to harvest | 5th leaf from tip | 15 - 20 | |
| D. Flowering to early fruiting | Petiole of 6th leaf from tip | 25 - 30 | |
| Lettuce, headf (Lactuca sativa, Crop File 1.03.526) | |||
| A. Rosette | MRM leaf | 30 - 50 | |
| B. Heading | MRM wrapper leaf | 20 - 40 | |
| C. Maturity | MRM wrapper leaf | 25 - 40 | |
| D. Seasonal monitoring | Midrib of MRM wrapper leaf | 30 - 50 | |
| Lettuce, Romaineg (Lactuca sativa, longifolia variety, Crop File 1.03.527) | |||
| A. 8-leaf | MRM leaf | 30 - 50 | |
| B. Mature plants | Wrapper leaf | 25 - 30 | |
| Mung beans (Vigna radiata, Crop File 1.03.605) | |||
| A. Pre-bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| Muskmelonh (Cucumis melo, Crop File 1.03.610) | |||
| A. Early growth (less than 12 inch vines) | 5th leaf from tip | 15 - 20 | |
| B. Flowering to early fruiting | 5th leaf from tip | 15 - 20 | |
| C. Early fruiting to harvest | 5th leaf from tip | 15 - 20 | |
| D. Flowering to early fruiting | Petiole of 6th leaf from tip | 25 - 30 | |
| Muskmelonh (Cucumis melo, Crop File 1.03.610) | |||
| A. Early growth (less than 12 inch vines) | 5th leaf from tip | 15 - 20 | |
| B. Flowering to early fruiting | 5th leaf from tip | 15 - 20 | |
| C. Early fruiting to harvest | 5th leaf from tip | 15 - 20 | |
| D. Flowering to early fruiting | Petiole of 6th leaf from tip | 25 - 30 | |
| Onions (Allium cepa, Crop File 1.03.665) | |||
| A. 2-leaf to 6-leaf stage | Whole tops | 20 - 25 | |
| B. Early bulbing (8-leaf to 10-leaf stage) | Whole tops | 20 - 25 | |
| C. Mid-growth, mid-bulbing (12-leaf to 13-leaf stage) | MRM (tallest) leaf | 30 - 40 | |
| D. Late-bulb to early maturity | MRM (tallest) leaf | 30 - 40 | |
| Peas, green (Pisum sativum), 1.03.727) | |||
| Peas, Southernj (Vigna unguiculata, 1.03.728) | |||
| A. Pre-bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| B. First bloom | MRM trifoliate w/ petiole | 15 - 20 | |
| Pepper, chili or jalepeno (Capsicum annuum, Crop File 1.03.736) | |||
| A. Early growth, first bloom | MRM leaf | 20 - 25 | |
| B. Early fruit set | MRM leaf | 20 - 25 | |
| C. Seasonal monitoring | Petiole of MRM leaf | 30 - 40 | |
| Pepper, bell (Capsicum annuum, Crop File 1.03.735) | |||
| A. Early growth, prior to first bloom | MRM leaf | 20 - 25 | |
| B. First bloom to fruit fill | MRM leaf | 20 - 25 | |
| C. Fruiting, mature plants | MRM leaf | 20 - 25 | |
| D. Early harvest | MRM leaf | 20 - 25 | |
| E. Seasonal monitoring | Petiole of MRM leaf | 30 - 40 | |
| Potatok (Solanum tuberosum, Crop File 1.03.769) | |||
| A. Vegetative growth | Petiole of MRM leaf | 30 - 40 | |
| B. Tuber initiation | Petiole of MRM leaf | 30 - 40 | |
| C. Tuber bulking | Petiole of MRM leaf | 30 - 40 | |
| Squash, summerl (Curbita species, Crop File 1.03.850) | |||
| A. Early bloom | MRM leaf | 20 - 25 | |
| B. Midbloom to early fruiting | MRM leaf | 20 - 25 | |
| Squash, winterl (Curbita species, Crop File 1.03.851) | |||
| A. Early bloom | MRM leaf | 20 - 25 | |
| B. Midbloom to early fruiting | MRM leaf | 20 - 25 | |
| Strawberry (Fragaria × ananassa, Crop File 1.03.855) | |||
| A. Early harvest | MRM trifoliate w/ petiole | 20 - 25 | |
| B. Mid-season | MRM trifoliate w/ petiole | 20 - 25 | |
| C. Seasonal monitoring | Petiole of MRM trifoliate | 30 - 50 | |
| Sweet potato (Ipomoea batatas, Crop File 1.03.880) | |||
| A. Early vining | MRM leaf | 20 - 25 | |
| B. Mid-season (prior to root enlargement) | MRM leaf | 20 - 25 | |
| C. Root enlargement | MRM leaf | 20-25 | |
| D. Prior to harvest | MRM leaf | 20 - 25 | |
| Tomato (Lycopersicon lycopericum, Crop File 1.03.920) | |||
| A.. Five-leaf stage | MRM leafm | 20 - 25 | |
| B. First flower | MRM leafm, usually 4th to 5th | 20 - 25 | |
| C. Early fruit set | MRM leafm, usually 4th to 5th | 20 - 25 | |
| D. First ripe fruit | MRM leafm, usually 4th to 5th | 20 - 25 | |
| E. During harvest period | MRM leafm, usually 4th to 5th | 20 - 25 | |
| Turnip (Brassica rapa, Crop File 1.03.940) | |||
| A.. Five-leaf stage | MRM leafm | 20 - 25 | |
| B. First flower | MRM leafm, usually 4th to 5th | 20 - 25 | |
| C. Early fruit set | MRM leafm, usually 4th to 5th | 20 - 25 | |
| D. First ripe fruit | MRM leafm, usually 4th to 5th | 20 - 25 | |
| E. During harvest period | MRM leafm, usually 4th to 5th | 20 - 25 | |
| Turnip (Brassica rapa, Crop File 1.03.940) | |||
| Mid growth (1-inch diameter roots) | MRM leaf w/ petiole | 25 - 35 | |
| Watermelon (Citrullis lanatus, Crop File 1.03.955) | |||
| A. Early growth to flowering | MRM leaf w/ petiole | 25 - 50 | |
| B. Early fruiting | MRM leaf w/ petiole | 25 - 50 | |
| C. Fruiting to harvest | MRM leaf w/ petiole | 25 - 50 | |
| D. Seasonal monitoring | Petiole of MRM leaf | 20 - 25 | |
| Zucchini (Curbita pepo, Crop File 1.03.990 | |||
| A. Early bloom | MRM leaf | 20 - 25 | |
| B. Midbloom to early fruiting | MRM leaf | 20 - 25 | |
*MRM = most recently mature
a also: string bean, French bean, snap bean, common bean
b also: butter bean
c also: muskmelon, rockmelon, sweet melon
d also: string bean, French bean, snap bean, common bean
e also: Crenshaw melon, casaba melon, winter melon
f also: Iceberg lettuce, crisphead lettuce, Boston lettuce, butterhead lettuce, Bibb lettuce, etc.
g also: Cos lettuce
h also: cantaloupe, rockmelon, sweet melon
i also: black-eyed peas, purple-hulled peas, cowpeas
k ranges may differ for individual varieties
l includes acorn squash, butternut squash, cushaw squash, Hubbard squash, and others
m "leaf" includes main petiole, allthe leaflets, and their petioliules