Sampling
Plant Tissue Sampling
Guidelines for plant tissue sampling requirements.
Sampling Schedule
Below are sampling instructions to help optimize the most accurate results. These instructions include when to sample, plant part to sample, and number of leaves required.
| Crop | When to Sample | Plant Part to Sample | Number of Leaves in Sample |
|---|---|---|---|
| Alfalfa | Early growth up to 1/10 Bloom stage | Entire top 15 cm of plant | 45-55 |
| Apple | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Apricot | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Beans | Seedling stage | Entire above ground portion | 25-30 |
| Beans | Before or during initial flowering | Youngest mature leaves from the top of the plant | 25-30 |
| Beets | Before root or bulb enlargement | Centre mature leaves | 25-35 |
| Broccoli | Before heading | First mature leaves from centre of whorl | 10-20 |
| Cabbage | Before heading | First mature leaves from centre of whorl | 10-20 |
| Carnations | Pinched plants | 5th and 6th leaf pair from top of primary laterals | 20-30 |
| Carnations | Unpinched plants | 4th and 5th leaf pair from terminal of plant | 20-30 |
| Carrots | Before root or bulb enlargement | Centre mature leaves | 25-35 |
| Celery | Early to mid-growth | Petiole and leaf of youngest mature leaf | 20-30 |
| Cereal Grains | Prior to heading | First 4 leaf blades from top of plant | 30-40 |
| Cereal Grains | Seedling stage (less than 30 cm) | All the above ground portion of plant | 50-75 |
| Cherry | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Chrysanthemums | Before and during early flowering | Youngest mature leaves on flowering stem | 20-30 |
| Clover and Other Legumes | Prior to bloom | Mature leaf blades about 1/3 of the way down the plant top | 50-60 |
| Coffee | Early to mid-season | Mature leaves of current year’s growth | 40-50 |
| Confer | In spring, when it has about 2 inches of new growth | Collect 2 inches of new tip growth (entire tip including stem). Collect from the same side of the tree at the same height on each tree. | approx. 30 tips |
| Corn | Seedling stage (less than 30 cm tall) | All the above ground portion | 25-30 |
| Corn | Just before tasselling | The fully developed leaf below the whorl | 15-20 |
| Corn | Tasselling to silking | The leaf at the ear node or the one above or below it | 15-20 |
| Cotton | Early growth, at first bloom and when first squares appear | Youngest fully mature leaves on main stem | 30-35 |
| Cucumber | Early stage of growth prior to fruit set | 4th to 6th leaf from terminal on main stem | 20-25 |
| Cucurbits (Cucumber, Melons, etc.) | Early stage of growth prior to fruit set | 4th to 6th leaf from terminal on main stem | 20-25 |
| Deciduous Fruit (Apple, Apricot, Almond, Cherry. Peach, Pear, Prune) | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Forage and Pasture Grasses | Before head emergence or at the stage of best quality | The uppermost leaf blades | 50-60 |
| Grains(Small, Including Rice) | Seedling stage(less than 30 cm) | All the above ground portion of plant | 50-75 |
| Grains(Small, Including Rice) | Prior to heading | First 4 leaf blades from top of plant | 30-40 |
| Grapes | During bloom period | Leaves and petioles opposite the flower cluster | 75-100 |
| Head Crops (Cabbage, etc) | Before heading | First mature leaves from center of whorl | 10-20 |
| Leaf Crops (Lettuce, Spinach, etc.) | Before mid-growth | Youngest mature leaf | 30-50 |
| Lettuce | Before mid-growth | Youngest mature leaf | 30-50 |
| Lemon, Lime | During autumn growth flush | Mature leaves from last flush of growth on non-fruiting terminals | 30-40 |
| Melons | Early stage of growth prior to fruit set | 4th to 6th leaf from terminal on main stem | 20-25 |
| Milo-Sorghum | Before or at heading | 2nd leaf from top of plant | 20-25 |
| Onions | Before root or bulb enlargement | Centre mature leaves | 25-35 |
| Orange | During autumn growth flush | Spring cycle leaves, 4 to 7 months old from non-fruit-bearing terminals | 25-30 |
| Ornamental Trees and Shrubs | Current year’s growth | Fully mature leaves | 30-75 |
| Peach | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Peanuts | Before or at bloom stage | Youngest fully developed leaves from top of the plant | 40-45 |
| Pear | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Peas | Before or during initial flowering | Leaves from the 3rd node down from the top of the plant | 30-50 |
| Pecans | After the end of terminal growth | Mature leaves from terminal shoots, taking the pairs from the middle of the leaf | 30-45 |
| Plum | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Potato | During vegetative growth | 3rd to 6th leaf back from growing tip | 30-50 |
| Pineapple | During vegetative growth | Young mature leaves | 10-15 |
| Poinsettias | Before and during early flowering | Most recently mature fully expanded leaf | 15-20 |
| Potato | During vegetative growth | 3rd to 6th leaf back from growing tip | 30-50 |
| Prune | Late summer just after the end of terminal growth | Youngest fully expanded leaf from non-fruiting terminals | 75-100 |
| Radish | Before root or bulb enlargement | Centre mature leaves | 25-35 |
| Raspberry | From early growth through midseason | Youngest mature leaves on lateral or primary canes | 25-40 |
| Rice | Prior to heading | First 4 leaf blades from top of plant | 30-40 |
| Rice | Seedling stage (less than 30 cm) | All the above ground portion of plant | 50-75 |
| Root Crops (Carrots, Beets, Onions, etc.) | Before root or bulb enlargement | Center mature leaves | 25-35 |
| Roses | Before and during early flowering | Upper mature leaves on the flowering stem | 25-30 |
| Small Grains (Including Rice) | Prior to heading | First 4 leaf blades from top of plant | 30-40 |
| Small Grains (Including Rice) | Seedling stage (less than 30 cm) | All the above ground portion of plant | 50-75 |
| Soybeans | Or prior to or during initial flowering | Fully developed leaves at the top of the plant | 20-30 |
| Soybeans | Seedling stage (less than 30 cm tall) | All the above ground portion | 20-30 |
| Spinach | Before mid-growth | Youngest mature leaf | 30-50 |
| Squash | Early stage of growth prior to fruit set | 4th to 6th leaf from terminal on main stem | 20-25 |
| Strawberry | From early vegetative growth to early fruiting state | Youngest fully expanded mature leaves | 50-70 |
| Sugar Beets | Before mid-season | Fully mature leaves midway between the younger center leaves and the oldest leaf whorl on the outside. | 30-35 |
| Sugar Cane | Up to 4 months old | 4th fully developed leaf from the top of the plant. | 25-30 |
| Sweet Corn | Before tasselling | The entire fully mature leaf below the whorl | 20-35 |
| Tobacco | Before bloom | Uppermost fully developed leaf | 8-12 |
| Tomato (Field) | Before early bloom stage | 3rd to 4th leaf back from growing tip | 20-35 |
| Tomato (Greenhouse) | Before bloom | Young plants: Leaves from 2nd and 3rd clusters | 20-35 |
| Tomato (Greenhouse) | Before bloom | Older plants: Leaves from 4th to 6th clusters | 20-35 |
| Turf | Anytime during growing season | Leaf blades, avoid soil contamination | 500 cc of material |
| Walnut | After the end of terminal growth | Middle leaflet pairs from mature shoots | 30-40 |
English 
Español de México