|
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 mid-season |
|
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 |
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