Plant Analysis HandBook


C. Owen Plank

Extension Agronomist - Soil Testing & Plant Analysis


AGRONOMIC CROPS



Crop: ALFALFA

Plant Part and Time:

Top 4 to 6 inches of plant taken prior to or at 1/10 bloom stage.

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Nitrogen (N)

3.00-5.00%

Low leaf N is due primarily to poor nodulation or ineffective nodules. If N is low apply a foliar application of molybdenum in late winter or early spring before new shoots reach 2 inches in height. Apply at the rate of 3 oz. of Mo (8. oz. of sodium molybdate) in 25 gallons of water/A. Low soil pH and low soil P levels can also result in low leaf N; therefore, it is important to maintain the proper soil fertility for optimum N fixation. Alfalfa does not respond favorably to topdress N applications, in fact, such treatment may inhibit Rhizobia bacteria and stimulate weed growth. Nitrogen content will decrease as the season progresses; therefore, low N may indicate late harvested forage.

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Phosphorus (P)

0.25-0.70%

Low P due to low soil test P and/or inadequate P fertilization. If P is low in the tissue apply 75-100 lbs. P2O5/A. For succeeding years soil test and follow soil test recommendations. Maintain soil pH at recommended level.

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Potassium (K)

2.00-3.50%

Low K due to low soil test K and/or inadequate K fertilization. If K is low in the tissue apply 100-200 lbs K2O/A, adjusting the rate based on the number of harvests remaining for the current growing season. Low K in the tissue may indicate late harvested forage. The K content of alfalfa will tend to decrease as the season progresses particularly the last cutting. High K levels indicate luxury consumption due to excessive fertilization. For succeeding years, soil test and follow soil test recommendations.

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Calcium (Ca)

0.80-3.00%

Low Ca due to low soil pH and/or low soil Ca. Also Ca content of the forage may be depressed following large K applications. Maintain soil pH at recommended level and split K application if more than 200 lbs K2O/A is recommended.

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Magnesium (Mg)

0.25-1.00

Low Mg due to low soil Mg, low soil pH and/or heavy applications of K fertilizers. Low Mg can be prevented by maintaining soil pH at recommended level using dolomitic limestone. Also split K applications when more than 200 lbs. K2O/A is recommended. If Mg is low in the forage, apply 25 lbs. Mg/A.

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Sulfur (S)

0.25-0.50%

Low S may occur on sandy soils, on soils under intensive management and where S-free containing fertilizers have been used for an extended period. Low S can normally be corrected by including 25 lbs. S/A in the fertilizer program. Maintain the N:S ratio between 10:1 to 15:1 for ruminant nutrition.

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Manganese (Mn)

25-100 ppm

Low Mn may occur on some sandy Coastal Plain soils when the pH is near or above pH 7.0. When low Mn levels are detected, include Mn in the succeeding fertilizer program at the rate of 10-15 lbs. Mn/A.. For the current season, apply a foliar application of Mn using 1 lb Mn/A as manganese sulfate or 0.5 lb Mn/A as chelated Mn in 20-25 gallons of water/A. Apply after each harvest when the alfalfa is about 4-6 inches high.

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Iron (Fe)

30-250 ppm

Deficiency not likely to occur. High Fe levels normally indicate soil or dust contamination.

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Boron (B)

20-80 ppm

Low B due to low soil B and/or inadequate B fertilizer. Boron deficiency can be corrected during the current season by applying 2 to 3 lbs B/A with the next split application of fertilizer and/or by applying a foliar application of B using 1/2 lb. B in 25 to 30 gallons of water/A. Apply the foliar spray after each harvest when plants are about 4 to 6 inches high. To prevent B deficiency in succeeding years include 3 lbs B/A annually in the fertilizer program.

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Copper (Cu)

5-30 ppm

Deficiency not likely to occur.

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Zinc (Zn)

20-70 ppm

Zinc deficiency is not a common occurrence in alfalfa, but low Zn may occur on coarse textured Coastal Plain soils when soil Zn is low and soil pH is near 7.0 or above. Zinc deficiency symptoms are usually evident at concentrations of approximately 10 ppm. If leaf Zn is 10 ppm or less, deficiency may be corrected in the current crop by applying a foliar application of Zn using 0.50 lb. Zn/A as zinc sulfate or zinc chelate in 25-30 gallons of water. Apply after each harvest when plants are about 4-6 inches high. For succeeding years include 3 to 5 lbs. Zn/A in the fertilizer program until the Zn level in the tissue is within the sufficiency range. If the Zn level is between 11-19 ppm include 3 to 5 lbs Zn/A in the fertilizer program until the Zn level in the tissue is within the sufficiency range.

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Aluminum (Al)

0-200 ppm

Element not a factor in plant nutrition. High levels are generally due to soil or dust contamination.

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Molybdenum (Mo)

1-5 ppm

Molybdenum is required for nodulation and nitrogen fixation and is recommended as a seed and foliar treatment. Low Mo in the plant is generally accompanied by low N. If low Mo is detected in that tissue apply Mo as described in the nitrogen section above. =====================================================

Crop: HYBRID BERMUDAGRASSES, (Coastal, Tifton-44, Tifton-78)

Plant Part and Time:

Upper half of the plant taken prior to seed head formation.

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Nitrogen (N)

2.00-2.60%

Deficiency due to inadequate or ineffective N fertilization. If nitrogen is low apply 75-100 lbs N/A after each harvest. High N is due to excessive fertilization and luxury consumption; therefore, reduce application rates. Nitrogen content will decrease with age of plants; therefore, low N may indicate late harvested grass.

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Phosphorus (P)

0.20-0.40%

Deficiency due to low soil test P and/or inadequate P fertilization. If P is low in the tissue apply 80-100 lbs P2O5/A. For succeeding years soil test and follow soil test recommendations. Maintain soil pH at recommended level.

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Potassium (K)

1.50-2.30%

Deficiency due to low soil test K and/or inadequate K fertilization. If K is low in the tissue, apply 150-300 lbs. K2O/A, adjusting the rate based on the number of harvests remaining for the current growing season. If more than 150 lbs. K2O/A is used, split the application. Potassium content will decrease with age of the plant; therefore, low K may indicate late harvested grass. The K content of well fertilized Coastal will approach the upper end of the sufficiency range at the first harvest and the lower end of the range at the last harvest. High K levels indicate luxury consumption due to excessive fertilization. For succeeding years soil test and follow soil test recommendations.

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Calcium (Ca)

0.25-0.50%

Deficiency is not likely to occur. Calcium content of plant will increase with age. Maintain soil at proper pH and level of other essential elements.

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Magnesium (Mg)

0.10-0.25%

Deficiency not likely to occur unless the soil pH and/or soil test Mg level is low. Deficiency may be induced by heavy applications of K and N fertilizers. Deficiency can be prevented by liming with dolomitic limestone. When Mg is low apply 25 lbs Mg/A.

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Sulfur (S)

0.15-0.25%

Sulfur deficiency may occur on sandy soils under intensive management and where low S containing fertilizers have been used for extended periods. Low S can normally be corrected by including 25 lbs. S/A in the fertilizer program. The optimum N:S ratio should be maintained between 10:1 to 15:1 for ruminant nutrition.

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Manganese (Mn)

20-300 ppm

Deficiency is not likely to occur. High Mn due to a low soil pH which indicates need to lime. Soil test and lime according to the recommendations.

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Iron (Fe)

50-200 ppm

Deficiency is not likely to occur.

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Boron (B)

5-15 ppm

Deficiency may occur on deep sandy soils. Deficiencies can be corrected by applying 1 lb. of actual B/A.

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Copper (Cu)

4-20 ppm

Deficiency is not likely to occur. High Cu levels may occur when sewage sludge or animal manures are applied in repeated heavy applications.

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Zinc (Zn)

15-70 ppm

Deficiency is not likely to occur. High Zn levels may occur when sewage sludge or animal manures are applied in repeated heavy applications.

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Aluminum (Al)

0-200 ppm

Element probably not a factor in plant nutrition. =====================================================

Crop: CORN, Dryland (Whole Plant)

Plant Part and Time:

Whole plants, less than 12-inch tall

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Nitrogen (N)

3.50-5.00%

Deficiency generally due to inadequate or ineffective N fertilization. When occurring at this stage, apply N fertilizer as soon as possible at a rate of 50 to 75 lbs. N/A. The method of application should place N within easy reach of the plant roots. Shallow placement is more desirable than deep placement.

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Phosphorus (P)

0.30-0.50%

Deficiency may be due to low soil P and/or inadequate P fertilization. Cool wet weather conditions can also induce a P deficiency even when the soil test level is medium or high. If the latter condition prevails, deficiency symptoms will disappear and the P content of the plants will increase as soil temperature increases. Corrective treatment is difficult to apply and may not be effective.

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Potassium (K)

2.50-4.00%

Deficiency due to low soil K and/or inadequate K fertilization. If K is low in the tissue and the soil test K level is low or medium, side-dress with 50 to 75 lbs K2O/A. If the soil test K level is high do not apply additional K2O. Avoid excessive applications as they could induce Mg deficiency.

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Calcium (Ca)

0.30-0.70%

Deficiency is not a common occurrence since the soil Ca level must be extremely low for a Ca deficiency to occur. Usually low Ca is associated with low soil pH. Deficiency can be corrected by liming. High Ca levels are due to a major element deficiency such as N, P, or K.

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Magnesium (Mg)

0.15-0.45%

Deficiency occurs when the soil Mg level and/or soil pH is low. Deficiency can also be induced by cool-wet growing conditions as well as by heavy applications of N and K fertilizers. If Mg in the tissue is low, broadcast 25 lbs Mg/A (Sul-Po-Mag, K-Mag, and magnesium sulfates) or apply a foliar application using 0.30 to 0.40 lbs. of Mg/A in 20 to 25 gallons of water. Repeat the foliar application in 10 to 14 days if symptoms persist. If the soil pH is less than 5.5 and plant Mg is low, a broadcast application of dolomitic limestone at the rate of 1000 lbs/A along with a foliar application of Mg at the rate of 3 lbs Mg/A in 20 to 25 gallons of water may be effective in controlling Mg deficiency.

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Sulfur (S)

0.20-0.50%

Low S may occur on sandy Coastal Plain soils where high analysis S-free fertilizers have been applied for several years. Low S levels may be avoided by including a minimum of 10 lbs. S/A in the fertilizer. When S is low in tissue, apply a minimum of 10 lbs. S/A, preferably with the sidedress N application.

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Manganese (Mn)

20-300 ppm

Deficiency is not likely to occur except on very sandy soils with a pH of 6.5 or higher or soils high in organic matter. Mn deficiency is more likely to occur when the soil is cool and wet under the conditions given above. The deficiency can be corrected by a foliar application of 1 to 2 lbs. Mn/A as manganese sulfate or 0.5 to 1.0 lb. Mn/A as manganese chelate in 20 to 25 gallons of water. If deficiency symptoms are still evident in 10 to 14 days repeat the application. High Mn is due to low soil pH and frequently associated with Mg deficiency. (See Mg discussion above).

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Iron (Fe)

50-250 ppm

Deficiency not likely to occur. High Fe test results normally indicate soil or dust contamination. An accurate Fe determination can only be made with washed leaves (See discussion on Washing to Remove Contaminates).

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Boron (B)

5-25 ppm

Deficiency is not likely to occur except on very sandy low organic matter soils. If these soil conditions exist and B in the tissue is low, apply a foliar application of B using 0.25 lb of actual B/A in 20-25 gallons of water. On heavier soils no corrective treatment is recommended at this stage of growth. Boron may be high on soils where B fertilizer has been applied for other crops. Boron levels in excess of 30 ppm are excessive.

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Copper (Cu)

5-20 ppm

Deficiency not likely to occur. High Cu levels may occur when soils have been treated with poultry or other animal manures.

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Zinc (Zn)

20-60 ppm

Deficiency likely to occur on sandy soils, low in organic matter (<1%), and soils that are near neutral in pH. A deficiency may be corrected by a foliar application of Zn at a rate of 0.50 lb. Zn/A as zinc sulfate or zinc chelate in 20 to 25 gallons of water. Zinc does not become toxic to corn until the Zn level exceeds 200 ppm.

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Aluminum (Al)

0-400 ppm

High Al levels are due either to soil contamination (Fe will also be high), extremely low soil pH or if the soil has been wet for a long period of time. There is no corrective treatment for current crop when Al is high.

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Molybdenum (Mo)

0.1-10.0 ppm

Deficiency not likely to occur. =====================================================

Crop: CORN, Dryland

Plant Part and Time:

Leaf below the whorl prior to tasseling.

Ear leaf at tasseling collected before the silks turn brown.

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Nitrogen (N)

Leaf below whorl 3.00-3.50%

Ear leaf 2.75-3.50%

Deficiency due to inadequate or ineffective N fertilization. When occurring prior to tasseling sidedress with 50-75 lbs. N/A. When occurring at silking, no corrective treatment is recommended.

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Phosphorus (P)

0.25-0.45%

Deficiency due to low soil P and/or inadequate P fertilization. Corrective treatment not recommended. Soil test and follow soil test recommendation for next crop.

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Potassium (K)

Leaf below whorl 2.00-2.50%

Ear leaf 1.75-2.25%

Deficiency due to low soil K and/or inadequate K fertilization. Corrective treatment not recommended. If K in the tissue is high, it is generally due to excessive K fertilization. Soil test and follow soil test recommendation. Avoid large applications of K fertilizer to prevent a possible inducement of a Mg deficiency. When plant is Mg deficient, the K level is usually high.

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Calcium (Ca)

0.25-0.50%

Deficiency is not likely to occur as the soil Ca level must be extremely low for a deficiency to occur. Usually low soil Ca is associated with low soil pH. Deficiency can be corrected by liming to maintain soil pH at approximately 6.0. High Ca levels are due to a major element (N, P, or K) deficiency.

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Magnesium (Mg)

0.13-0.30%

Deficiency occurs when the soil Mg level and/or soil pH is low and when prolonged cool-wet growing conditions prevail early in the season. Deficiency can also be induced by heavy applications of N and K fertilizer. Corrective treatment may be ineffective unless applied well in advance of tasseling. If low Mg is detected, apply a foliar application of Mg using 0.30 to 0.40 lbs. Mg/A as magnesium sulfate in 20-25 gallons of water or if the soil pH is above 5.4 and the soil Mg level is low apply 25 lbs of Mg/A. If the soil pH is less than 5.4 corrective treatment is not recommended.

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Sulfur (S)

Leaf below whorl 0.17-0.50%

Earleaf 0.15-0.50%

Low S may occur on sandy Coastal Plain soils where high analysis S-free fertilizers have been applied for several years. Avoid low S levels by including a minimum of 10 lbs. S/A in the fertilizer. For optimum corn yields the N:S ratio should be maintained between 10:1 to 15:1. When S is low in tissue, apply a minimum of 10 lbs. S/A. If sidedress nitrogen has not been applied, use a nitrogen sulfur combination material that contains 3 to 5% S as the nitrogen source. If sidedress N has been applied, apply a foliar application of S using 10 to 20 lbs of ammonium sulfate or 1/2 to 1 gallon of ammonium thiosulfate in 30 to 50 gallons of water/A. The latter material may cause some foliar burn, but should not adversely affect yields.

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Manganese (Mn)

15-300 ppm

Deficiency is not likely to occur except on sandy soils or soils high in organic matter with a pH of 6.5 or higher. The deficiency can be corrected by a foliar application of 1 to 2 lbs. Mn/A as manganese sulfate or 0.5 to 1.0 lb. Mn/A as manganese chelate in 20 to 25 gallons of water. High Mn is due to low soil pH and frequently associated with Mg deficiency (see Mg discussion above).

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Iron (Fe)

30-200 ppm

Deficiency is not likely to occur. High Fe test results normally indicate soil or dust contamination. An accurate Fe determination can only be made with washed leaves (See section on washing to Remove Contaminates).

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Boron (B)

4-25 ppm

Deficiency not likely to occur, except on very sandy low organic matter soils. Boron deficiency generally results in poor ear formation. If low leaf B and poor ear development are noted, B should be included in future corn fertilizer programs at the rate of 1 lb. B/A. Boron may be high in soils where B fertilizer has been applied for other crops. Boron levels in excess of 30 ppm are excessive. Since corn is quite sensitive to B, great care needs to be followed when this element is included in fertilizer treatments.

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Copper (Cu)

3-15 ppm

Deficiency not likely to occur. High Cu levels may occur when soils have been treated with poultry or other animal manures.

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Zinc (Zn)

15-60 ppm

Deficiency may occur on sandy soils low in organic matter (<1%) and soils that are near neutral in pH. A deficiency can be corrected by applying a foliar application of zinc at rates of 0.5 lb. Zn/A as zinc sulfate or zinc chelate in 20 to 25 gallons of water.

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Aluminum (Al)

0-200 ppm

High Al levels occur when the soil is wet for long periods or the soil pH is extremely low. However, Al does not easily enter the plant after about 3 weeks after emergence. High Al may also be due to soil or dust contamination in which case Fe is also usually high (See Fe discussion above).

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Molybdenum (Mo)

0.1-3.0 ppm

Deficiency not likely to occur. =====================================================

Crop: CORN, Irrigated (Whole Plant)

Plant Part and Time:

Whole plants, less than 12-inch tall

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Nitrogen (N)

3.50-5.00%

Deficiency is generally due to inadequate or ineffective N fertilization. When a deficiency occurs at this stage apply 40-50 lbs. N/A through the irrigation system or by conventional ground applicator as soon as possible. Avoid using rates higher than 50 lbs. N/A through the irrigation system.

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Phosphorus (P)

0.30-0.50%

Deficiency due to low soil P and/or inadequate P fertilization. Cool-wet growing conditions can induce a P deficiency even when the soil test P level is medium or high. Correction generally occurs as the soil temperature increases if there is sufficient P available for normal growth. Corrective treatment is difficult to apply and may not be effective.

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Potassium (K)

2.50-4.00%

Deficiency due to low soil K and/or inadequate K fertilization. If K is low apply 30 lbs. of K2O/A through the system. Rates should not exceed 30 lbs. K2O/A . Use a soluble grade of muriate of potash as the K source. Soluble grade potash contains 60 - 62% K2O and it can be readily dissolved and injected into the irrigation water.

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Calcium (Ca)

0.30-0.70%

Deficiency is not a common occurrence since the soil Ca level must be extremely low for a Ca deficiency to occur. Usually low Ca is associated with low soil pH. Prevent deficiency by maintaining the soil pH at approximately 6.0. High Ca levels are due to a major element deficiency such as N,P, or K.

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Magnesium (Mg)

0.15-0.45%

Deficiency occurs when the soil Mg level and/or soil pH is low. Deficiency can be induced by heavy applications of N and K fertilizer. If Mg is low in the tissue apply 5 lbs. of Mg/A as magnesium sulfate through the irrigation system; or apply 0.30 to 0.40 lbs. Mg/A, as magnesium sulfate, in 20-25 gallons of water by ground applicator.

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Sulfur (S)

0.20-0.50%

Low S may occur on sandy Coastal Plain soils where high analysis S-free fertilizers have been applied for several years. Avoid low S levels in the future by including a minimum of 10 lbs. S/A in the fertilizer. When S is low in the tissue, and no sulfur was applied in the preplant fertilizer, apply a minimum of 10 lbs. S/A using ammonium thiosulfate or other nitrogen-sulfur solutions.

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Manganese (Mn)

20-300 ppm

Deficiency not likely to occur except on very sandy soils with a pH of 6.5 or higher or soils high in organic matter. Mn deficiency is more likely to occur when the soil is cool and wet under the conditions given above. The deficiency can be corrected by applying multiple foliar applications of 1 lb Mn/A as manganese sulfate or 0.5 lb. Mn/A as manganese chelate in 20 to 25 gallons of water with a ground applicator, or by injecting 2 lbs. Mn/A as manganese sulfate through the irrigation system. Repeat the application in 10 to 14 days. High Mn is due to low soil pH and is frequently associated with low Ca and Mg levels.

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Iron (Fe)

50-250ppm

Deficiency is not likely to occur. High Fe test results normally indicate soil or dust contamination. An accurate Fe determination can only be made with washed leaves (See section on washing to remove contaminates).

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Boron (B)

5-25 ppm

Deficiency is not likely to occur except on sandy low organic matter soils. If B is low in the tissue apply a total of 2 lbs. of B/A through the system. Split the application applying 1 lb./A through the system as soon as possible and the remainder just prior to tasseling.

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Copper (Cu)

Deficiency is not likely to occur. High Cu levels 5-20 ppm may occur when soils have been treated with poultry or other animal manures.

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Zinc (Zn)

20-60 ppm

Deficiency is likely to occur on sandy soils,that are low in organic matter (<1%) and soils that are near neutral in pH. Low Zn is also likely to occur under cool-wet growing conditions. A deficiency may be corrected by applying a foliar spray of Zn at a rate of 0.50 lb. Zn/A as zinc sulfate or zinc chelate in 20-25 gallons of water by ground application or 2 lbs. Zn/A as zinc sulfate or 0.5 lb. Zn/A as zinc chelate applied through the system. Zinc does not become toxic to corn plants until the Zn level exceeds 200 ppm.

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Aluminum (Al)

0-400 ppm

High Al levels are due either to soil contamination (Fe will also be high), extremely low soil pH or if the soil has been wet for a long period of time. No immediate corrective treatment is recommended.

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Molybdenum (Mo)

0.1-10.0 ppm

Deficiency not likely to occur. =====================================================

Crop: CORN, Irrigated

Plant Part and Time:

Leaf below the whorl prior to tasseling.

Ear leaf at tasseling collected before the silks turn brown.

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Nitrogen (N)

Leaf below whorl 3.00-3.50%

Ear leaf 2.75-3.50%

Deficiency is due to inadequate or ineffective N fertilization. If nitrogen in the tissue is low prior to tasseling, apply 40-50 lbs. of N/A through the system. If N is low at tasseling reduce the N rate to 30 lbs./A . Excessively high N levels can result in induced S deficiency, unless adequate S levels are present.

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Phosphorus (P)

0.25-0.45%

Deficiency due to low soil P and/or inadequate P fertilization. Also, when corn is in the early stages of development (12-24) inches low P can be due to cool wet weather conditions even on soils with medium or high soil test P levels. Generally, P levels in the tissue will increase to sufficient levels as the soil temperature increases. Corrective treatment is difficult to apply and is not effective.

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Potassium (K)

Leaf below whorl 2.00-2.50%

Ear leaf 1.75-2.25%

Deficiency due to low soil K and/or inadequate K fertilization. If potassium is low prior to tasseling, apply 30 lbs. K2O/A through the system. Do not exceed rates of 30 lbs. K2O/A because foliar burn may occur at higher rates. Use a soluble grade of muriate of potash as the K source. Soluble grade potash contains 60-62% K2O and can be readily dissolved and injected into the irrigation water. If potassium is low in the ear leaf tissue (at tasseling), no corrective treatment is recommended for the current crop. Often when the K level is high in the tissue, Mg levels in the tissue will be at the low end of the sufficiency range. Avoid excessively high applications of K to prevent the development of low Mg levels.

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Calcium (Ca)

0.25-0.50%

Deficiency is not likely to occur as the soil Ca level must be extremely low for a deficiency to occur. Usually low soil Ca is associated with low soil pH. No corrective treatment is recommended for the current crop. Deficiency in succeeding crop can be avoided by liming to maintain soil pH at approximately 6.0. High Ca levels are due to a major element (N, P, or K) deficiency.

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Magnesium (Mg)

0.13-0.30%

Deficiency occurs when soil Mg levels and/or soil pH is low. Deficiency can be also induced by heavy application of N and K fertilizer. If low Mg is detected prior to tasseling, apply 5 lbs. of Mg/A as magnesium sulfate through the irrigation system; or apply 0.30 to 0.40 lbs. of Mg/A, as magnesium sulfate in 20-25 gallons of water by ground applicator. Corrective treatment at or after tasseling is not recommended.

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Sulfur (S)

Leaf below whorl 0.17-0.50%

Ear leaf 0.15-0.50%

Low S may occur on sandy Coastal Plain soils where high analysis S-free fertilizers have been applied. Low S levels may be avoided by including a minimum of 10 lbs. S/A in the fertilizer. If the sulfur level in the tissue is low or if the N:S ratio exceeds 18:1, apply a minimum of 10 lbs. S/A through the irrigation system. Ammonium thiosulfate and nitrogen-sulfur solutions are preferred sources. For optimum corn yields the N:S ratio should be maintained between 10:1 and 15:1.

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Manganese (Mn)

15-300 ppm

Deficiency not likely to occur except on very sandy soils or soils high in organic matter with a pH of 6.5 or higher. The deficiency can be corrected by injecting 2 lbs. Mn/A as manganese sulfate in the irrigation water. Application of Mn is not recommended after tasseling. High Mn is due to low soil pH and is frequently associated with Mg deficiency.

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Iron (Fe)

30-200 ppm

Deficiency not likely to occur. High Fe test results normally indicate soil or dust contamination. An accurate Fe determination can only be made with washed leaves (See section on washing to remove contamination).

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Boron (B)

4-25 ppm

Deficiency is not likely to occur, except on very sandy low organic matter soils. Boron deficiency can result in poor ear formation. If B is low at the leaf below the whorl stage, apply 2 lb.of B/A through the system. Split the application, applying 1.0 lb./A as soon as possible and the remainder just prior to tasseling. If B is low at the ear leaf stage and poor ear development is noted in the current crop, include B in future corn fertilizer programs at the rate of 2 lbs. B/A. No corrective treatment is recommended for current crop if B is low at the ear leaf stage. Boron may be high in soils where B fertilizer has been applied for other crops. Boron levels greater than 30 ppm are excessive. Since corn is quite sensitive to B, great care needs to be exercised when this element is included in fertilizer treatments.

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Copper (Cu)

3-15 ppm

Deficiency is not likely to occur. High Cu levels may occur when soils have been treated with poultry or other animal manures.

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Zinc (Zn)

15-60 ppm

Deficiency is likely to occur on sandy soils which are low in organic matter (<1%) and soils that are near neutral in pH. A deficiency can be corrected by applying a foliar application of zinc using 0.50 lb.of Zn/A as zinc sulfate or zinc chelate in 20 to 25 gallons of water by ground application or by injecting 2 lbs. Zn/A as zinc sulfate or 0.5 lb. Zn/A as zinc chelate through the system. Zinc does not become toxic to corn plants until the Zn level exceeds 200 ppm.

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Aluminum (Al)

0-200 ppm

High Al levels occur when the soil is wet for long periods or the soil pH is extremely low. However, Al does not easily enter the plant after about 3 weeks after emergence. High Al may also be due to soil or dust contamination in which case Fe is also usually high (See Fe discussion above).

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Molybdenum (Mo)

0.1-3.0 ppm

Deficiency not likely to occur. =====================================================

Crop: COTTON

Plant Part and Time:

Upper mature leaves on vegetative stems taken prior to or at first bloom or when first squares appear.

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Nitrogen (N)

3.50-4.50%

Deficiency due to inadequate N fertilization and/or ineffective N application. Poor root growth can result in a N deficiency. Topdressing with 30 to 40 lbs. N/A may be sufficient to correct a N deficiency. High N concentrations can result in excessive vegetative growth, making the plants more susceptible to insect injury. Follow nitrogen fertilizer recommendations to avoid both deficiencies and excesses. The nitrogen status of the crop can best be monitored through the petiole analysis program.

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Phosphorus (P)

0.30-0.50%

Less than sufficient due to low soil P level and/or inadequate P fertilization. Low soil pH or restricted root growth may reduce P uptake. Soil test and follow the soil test recommendation. No corrective treatment recommended for the sampled crop.

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Potassium (K)

1.50-3.00%

Less than sufficient due to low soil K test level and/or inadequate K fertilization. Soil test and follow the soil test recommendation. No corrective treatment recommended for the sampled crop.

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Calcium (Ca)

2.00-3.00%

Less than sufficient due to very low soil pH. Deficiencies may be induced by excessive K fertilization rates. Soil test and lime to adjust the soil pH to approximately 6.0.

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Magnesium (Mg)

0.30-0.90%

Less than sufficient due to low soil pH (less than 5.4) and/or low soil test Mg level. If deficiency is detected, soil apply 25 lbs Mg/A using a soluble source of Mg, or apply a foliar application at a rate of 0.30 to 0.40 lbs. Mg/A as magnesium sulfate in 20 to 25 gallons of water. Repeated applications may be necessary during the growing season. For succeeding crops soil test and apply limestone and fertilizer based on soil test recommendation.

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Sulfur (S)

0.25-0.80%

Less than sufficient due to low soil S level. No corrective treatment is recommended for current crop, however, for future crops a minimum of 10 lbs. S/A should be included in the fertilizer program.

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Manganese (Mn)

25-350 ppm

Deficiency not likely to occur in most Georgia soils. High Mn concentrations indicate low soil pH. If the Mg level in the leaf tissue is less than 0.30% and the Mn level greater than 350 ppm, liming with dolomitic limestone is essential to prevent Mg deficiency and a possible Mn toxicity.

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Iron (Fe)

50-250 ppm

Deficiency not likely to occur. High Fe test results indicate soil or dust contamination. An accurate Fe determination can only be obtained with washed leaves.

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Boron (B)

20-60 ppm

Low B is likely to occur on near neutral, deep sandy soils low in organic matter. If low B is detected apply a foliar application of B at the rate of 0.2 lb B/A in 20-25 gallons of water or in the insecticide spray. Multiple applications not to exceed 0.6 lb. B/A can be made.For subsequent cotton crops boron should be included in the fertilizer program or insecticide spray program at the rate of 0.5 lb./A. Boron deficiency may be intensified during droughty periods.

------------------------

Copper (Cu)

5-25 ppm

Deficiency not likely to occur.

------------------------

Zinc (Zn)

20-200 ppm

Deficiency may occur on near neutral, deep sandy soils low in organic matter. Soils recently limed may produce Zn deficient plants. Soil test and include Zn in the fertilizer treatment if the soil test is low and the soil pH is greater than 6.0. Deficiency symptoms will appear when the Zn level in the leaf tissue is less than 16 ppm. A foliar application of Zn will generally correct the deficiency, applying 0.5 lb. Zn/A, as zinc sulfate or 0.25 lb. Zn/A as zinc chelate.

------------------------

Aluminum (Al)

200 ppm

High concentrations in the leaf tissue are primarily due to anaerobic conditions such as poor drainage or compacted soils. Acid subsoils or restricted root growth may cause high Al uptake. If both Fe and Al are high, probably due to soil and dust contamination, see Fe discussion above.

Crop: PEANUTS

Plant Part and Time:

Upper mature leaves taken prior to or at bloom stage

-------------------------

Nitrogen (N)

3.00-4.50%

Low leaf N is primarily due to inadequate nodulation or ineffective nodules. Examine root system to determine extent of nodulation. Excessive application of N fertilizer at planting may reduce the number of nodules and effectiveness of nodule bacteria. Low soil pH and other deficiencies can result in a N deficiency; therefore, maintain the proper soil fertility level for optimum nitrogen fixation. Sidedressing with 50 lbs. N/A will normally correct a N deficiency in a developing plant.

------------------------

Phosphorus (P)

0.20-0.50%

Less than sufficient due to low soil P test level and/or inadequate P fertilization. No corrective treatment is recommended for the sampled crop. For future crops, soil test and follow the soil test recommendation.

------------------------

Potassium (K)

1.70-3.00%

Less than sufficient due to low soil K test level and/or inadequate K fertilization. No corrective treatment is recommended for the sampled crop. For future crops, soil test and follow the soil test recommendation.

------------------------

Calcium (Ca)

1.25-2.00%

Less than sufficient due to low soil pH and/or low soil test Ca level. Soil test and apply gypsum according to current soil test recommendations. Application of gypsum is not generally necessary if the soil pH is maintained around 6.0 and the soil test Ca level on samples taken from the pegging zone (3-inches deep) 10-14 days after planting is 500 lbs. Ca/A or greater.

------------------------

Magnesium (Mg)

0.30-0.80%

Less than sufficient due to low soil pH (less than 5.4) and/or low soil test Mg level. For corrective treatment, apply a foliar application of Mg, using 3-4 lbs. of magnesium sulfate per acre in 20-30 gallons of water. Repeated applications may be necessary at 10-14 day intervals. For future crops, soil test prior to planting and follow soil test lime recommendations applying dolomitic limestone to correct soil acidity. If lime is not recommended, apply 25 lbs. of elemental Mg per acre prior to planting.

------------------------

Sulfur (S)

0.20-0.35%

Sulfur levels are usually maintained by fungicide and gypsum applications and deficiency is not likely to occur. No corrective treatment recommended for current crop.

------------------------

Manganese (Mn)

20-350 ppm

Manganese deficiencies may occur on sandy soils with a pH greater than 6.3. If Mn deficiency occurs, apply a broadcast spray of Mn using 0.5 lb Mn/A as manganese sulfate or 0.15 to 0.25 lb Mn/A as chelated Mn in 20 gallons of water per acre. If symptoms persist, the spray should be repeated at 2 week intervals. In most cases, multiple applications will be required. High Mn levels are generally due to low soil pH. Manganese levels may be as high as 600-800 ppm before being toxic.

------------------------

Iron (Fe)

50-300 ppm

Deficiency is not likely to occur. High Fe test results normally indicate soil or dust contamination. An accurate Fe determination can only be obtained with washed leaves. (See section on sample preparation).

------------------------

Boron (B)

20-60 ppm

Deficiency can occur on near neutral deep sandy soils, low in organic matter. Boron should be included in the fertilizer treatment. If the boron level is low, apply a foliar application using 0.50 lb. of actual B/A in 20-25 gallons of water. Boron applications should not be made after pod initiation as little benefit will be realized after this period.

------------------------

Copper (Cu)

5-20 ppm

Copper deficiency is not likely to occur as levels 5-20 ppm are generally greater than 5 ppm. When Cu base fungicides are used, the Cu values can be very high (100 ppm or better) for unwashed leaves.

------------------------

Zinc (Zn)

20-60 ppm

Deficiency is not likely to occur except on high pH soils. Zinc levels above 60 ppm are excessive and zinc toxicity may occur on low pH soils when leaf Zn levels are above 110 ppm. A low level of leaf Ca is often associated with zinc toxicity in peanuts. Zinc toxicity may be more clearly identified by evaluating the Ca:Zn ratio in the leaf tissue. When the nutrient concentrations are converted to the same units (e.g. either % or ppm) a Ca:Zn ratio less than 45-50:1 is fairly indicative of zinc toxicity (NOTE: To convert ppm to %, move the decimal four (4) places to the left, e.g. 100 ppm = 0.1%

------------------------

Aluminum (Al)

0-200 ppm

Aluminum is not an essential element. When both Al and Fe test high, the leaves are probably soil or dust contaminated. (See Fe discussion above.)

------------------------

Molybdenum (Mo)

0.1-5.0 ppm

Deficiency not likely to occur, although the Mo requirement is high compared to other crops for normal nodule function (see N section above). Molybdenum is not needed when the soil is properly limed. =====================================================

Crop: SOYBEANS

Plant Part and Time:

Upper mature leaves taken prior to or at initial seed set

-------------------------

Nitrogen (N)

4.25-5.00%

Low leaf N is primarily due to inadequate nodulation or ineffective nodules. Examine root system to determine extent of nodulation. At planting, the application of ammoniacal forms of N fertilizer may reduce the number of nodules and effectiveness of nodule bacteria. Low soil pH, other nutrient deficiencies and nematodes can also result in N deficiency; therefore maintain the proper soil fertility level for optimum N fixation. Sidedressing with 50 lbs. N/A will normally correct a N deficiency for an already developing plant.

------------------------

Phosphorus (P)

0.25-0.50%

Less than sufficient due to low soil P test level and/or inadequate P fertilization. Soil test and follow the soil test recommendation. No corrective treatment recommended for the sampled crop.

------------------------

Potassium (K)

1.75-2.50%

Less than sufficient due to low soil K test level and/or inadequate K fertilization. Soil test and follow the soil test recommendation. No corrective treatment recommended for the sampled crop.

------------------------

Calcium (Ca)

0.50-1.50%

Less than sufficient due to low soil pH and/or low soil test Ca level. Soil test and lime as recommended. Soil pH should be maintained at approximately 6.0.

------------------------

Magnesium (Mg)

0.25-0.80%

Less than sufficient due to low soil pH (generally less than 5.4) and/or low soil Mg. When Mg is low in the tissue (<0.25%), a foliar application of Mg may be effective in alleviating this problem. Apply at the rate of 0.30 to 0.40 lbs. Mg/A as magnesium sulfate in 25-30 gallons of water per acre. For future crops, soil test and apply limestone and fertilizer based on soil test recommendations.

------------------------

Sulfur (S)

0.20-0.60%

Low S may occur on sandy soils where S-free fertilizers have been applied. No corrective treatment is recommended for current crop, however, for future crops, include a minimum of 10 lbs. S/A in the fertilizer.

------------------------

Manganese (Mn)

15-200 ppm

Deficiency occurs when the soil pH is near neutral or above on very sandy soils or soils high in organic matter. When Mn deficiency occurs, apply a foliar application of Mn using0.5 lb. Mn/A as manganese sulfate or 0.25 lb. Mn/A as MnEDTA in 10 to 20 gallons of water. If symptoms persist, apply a application at the above rate. Manganese in excess of 200 ppm can cause yield reductions. Crinkle leaf may be observed when the leaf Mn level exceeds 500 ppm. Excessive Mn levels can usually be corrected by liming the soil to pH 6.0-6.5

------------------------

Iron (Fe)

50-300 ppm

Deficiency not likely to occur except on soils where the pH is greater than 7.0 and the soil sandy in texture and/or high in organic matter content. High Fe test results normally indicate soil or dust contamination. Aluminum will also be high. An accurate Fe determination can only be obtained with washed leaves.

------------------------

Boron (B)

20-60 ppm

Deficiency likely to occur on near neutral deep sandy soils, low in organic matter. Soybeans are not particularly sensitive to boron and can develop normally even in low B soils.

------------------------

Copper (Cu)

5-30 ppm

Deficiency is not likely to occur.

------------------------

Zinc (Zn)

20-70 ppm

Deficiency is not likely to occur, even on soils in which the soil test Zn level may be low. If low Zn is detected in the tissue, apply a foliar application of Zn using 0.5 to 1.0 lb. Zn/A as zinc sulfate or 0.25 to 0.50 lb. Zn/A as zinc chelate in 25-30 gallons of water/A.

------------------------

Aluminum (Al)

0-200 ppm

Aluminum is not an essential element. High Al test values indicate poor soil aeration due to soil compaction or poor drainage. When both Al and Fe test high, the leaves are probably soil or dust contaminated (See Fe discussion above).

------------------------

Molybdenum (Mo)

0.1 - 5.0 ppm

Molybdenum has been found to be beneficial and is recommended as a seed treatment. It is doubtful that Mo would be sufficiently low to test below the sufficiency range in the leaf tissue on most Georgia soils that have been properly limed. =====================================================

Crop: TOBACCO

Plant Part and Time:

Uppermost fully developed leaf at bloom stage.

-------------------------

Nitrogen (N)

3.50-4.25%

Deficiency due to inadequate N fertilization and/or ineffective N application. No corrective treatment recommended for the sampled crop. In future crops, follow current N fertilizer recommendations.

------------------------

Phosphorus (P)

0.27-0.50%

Deficiency due to inadequate P fertilization and/or low soil P test level. Normally tobacco soils are over fertilized with P. Follow soil test recommendations for P closely to avoid deficiencies or excesses.

------------------------

Potassium (K)

2.50-3.20%

Deficiency due to inadequate K fertilization and/or low soil K test level. Normally tobacco soils are heavily fertilized with K. Follow soil test recommendation for K closely to avoid deficiencies or excesses. Heavy applications of K can induce a Mg deficiency. (See Mg discussion below.)

------------------------

Calcium (Ca)

Deficiency not likely to occur if the soil pH and 1.50-3.50%level of soil test K is maintained within the desired range. On most tobacco soils, when Ca is low in the leaf tissue, some type of root damage or root restriction will be evident.

------------------------

Sulfur (S)

0.20-0.60%

Low sulfur levels may occur if grown on coarse textured sandy soils that are low in organic matter and where S-free fertilizers have been used for an extended period. Heavy leaching spring rains may accentuate the problem. No corrective treatment is recommended for low S level in current crop; however, for future crops, include S in the fertilizer program to supply a minimum of 10 lbs. S/A.

------------------------

Magnesium (Mg)

0.20-0.65%

Low Mg is likely to occur when the soil pH is less than 5.4 and/or the soil test Mg level is low. If the Mg level is low, soil apply 25 lbs Mg/A using a soluble source of Mg. For future crops, soil test and follow the soil test recommendations. If limestone is recommended, use a high Mg grade (10-12% Mg) source. Also recommend the use of Sul-Po-Mag or K-Mag as the source of K and supplemental Mg.

------------------------

Manganese (Mn)

20-250 ppm

Deficiency may occur on soils which have been over-limed and that are low in Mn. If low levels are detected, apply a foliar application of Mn using 0.5 lb. Mn/A as manganese sulfate in 20 to 25 gallons of water. High Mn due to low soil pH and the effects of heavy fertilization.

------------------------

Iron (Fe)

50-200 ppm

Deficiency not likely to occur. High Fe due primarily to soil or dust contamination.

------------------------

Boron (B)

20-50 ppm

Deficiency is not likely to occur.

------------------------

Copper (Cu)

5-60 ppm

Deficiency is not likely to occur.

------------------------

Zinc (Zn)

20-80 ppm

Deficiency is not likely to occur.

------------------------

Aluminum (Al)

0-200 ppm

High Al suggests poor aeration or root damage of some kind. If Fe and Al are both high, then high Al probably due to soil or dust contamination. See Fe discussion above.

------------------------

Molybdenum (Mo)

Sufficiency range not known. =====================================================

Crop: TURFGRASS (General)

Plant Part and Time:

Above ground portion clipped just above ground level at least two days after regrowth.

-------------------------

Nitrogen (N)

2.20-4.00%

Nitrogen is the nutrient most commonly found to be low in turf grasses and is generally due to inadequate fertilization, heavy leaching rains, over-irrigation or possible root damage. N deficiency may be manifested as a light green color, slow growth rate or excessive seed head production. If a deficiency is detected, apply N according to soil test recommendations being sure to split applications where leaching may be a problem.

------------------------

Phosphorus (P)

0.30-0.70%

Deficiency is usually due to low soil P, cool-wet growing conditions, or excessively low soil pH. If deficiency is detected, apply phosphorus and limestone based on soil test recommendations. High levels of P generally pose more problems with intensively managed turf than deficiencies.

Excessive P levels in the leaves can cause deficiencies of other nutrients, particularly iron. High P to K ratios in leaf tissue increases winterkill in bermudagrass and St. Augustinegrass. When high P is detected, omit P from the fertilization program until P is within acceptable limits. In most instances three or more years may be required.

------------------------

Potassium (K)

1.50-3.00%

Low K is generally due to low soil test K levels, inadequate K fertilization or when grass is grown on coarse textured sandy soil that is subject to leaching. Low K may also be associated with low N fertilization. When soil K is adequate, N fertilization increases the uptake of K by the grass. When low K is detected in the tissue, apply potash and nitrogen based on soil test recommendations. When K drops below 1.00% in the tissue, deficiency symptoms appear and are characterized by spindly growth (narrow leaves, thin turf), leaf tip burn, reduced wear, cold, and disease tolerance and reduced growth rate. Excessive K levels may induce Mg deficiency. If high K levels are detected in the tissue, reduce the K fertilization rate or omit K from the program until K is within the sufficiency range.

------------------------

Calcium (Ca)

0.20-1.25%

Grasses are able to take up Ca under a wide range of soil conditions, and it is rarely deficient. If low levels are detected, check for low soil pH and apply limestone based on recommendations. A high Ca level may indicate some other nutrient deficiency or disorder.

------------------------

Magnesium (Mg)

0.15-0.60%

Low levels may occur on sandy soils, soils with low pH and low Mg, where high rates of NH4-N and K fertilizers have been applied, and where clippings are continuously removed. If low levels are detected, include Mg in the fertilization program at the rate of 0.50 lb. Mg per 1000 sq. ft. or if soil pH is low and limestone is required, apply dolomitic limestone according to soil test recommendations. Excessively high Mg in tissue is not a common occurrence.

------------------------

Sulfur (S)

0.20-0.40%

Low S may occur on sandy soils low in organic matter, where S-free fertilizers have been used, following extensive periods of heavy rainfall, where grass has been over-irrigated, and where high application rates of N have been applied. The ratio of N to S is as important as the S content itself and should not exceed 20:1. Ideally the N:S ratio should be approximately 14:1 for optimum growth and turf quality. If S is low and/or the N:S ratio exceeds 20:1 include 0.25-0.50 lb. S per 1000 sq. ft. in the fertilization program. Sulfur may be supplied as gypsum, elemental sulfur, or sulfur containing fertilizers.

------------------------

Manganese (Mn)

20-300 ppm

Deficiencies are rare but may occur occasionally on sandy soils that are low in Mn, high in organic matter, and when the soil pH is 6.8 or higher. Mn deficiencies can be corrected by applying a foliar application of manganese sulfate or manganese chelate by dissolving 2 ounces of manganese sulfate or 1 ounce of manganese chelate in 1 gallon of water and spraying at the rate of 1/2 gallon per 1000 sq. ft. Repeated applications will be required to prevent reoccurrence of the deficiency. Excessive Mn levels can occur in some turfgrasses when the soil pH is less than 5.5, or where soils are consistently overwatered. High Mn levels can be corrected by proper liming, proper irrigation practices and by improving drainage on waterlogged soils.

------------------------

Iron (Fe)

30-200 ppm

Iron determinations are invalid unless samples are properly washed to remove soil contaminates. Generally if Fe and Al levels are both high it is due to contamination rather than inherent levels in the grass. Iron deficiency can occur on high pH soils (7.0 or higher), during periods of cool temperatures, where grasses are overwatered and where soil P levels are excessively high. Iron deficiency is best controlled by applying a foliar application of iron as iron sulfate or iron chelate at a rate of 0.50 ounce of Fe per 1000 sq. ft. Repeated applications may be needed indefinitely to prevent reoccurrence of the deficiency. Do not apply foliar applications of iron to grasses in the heat of the day. Soil applications of Fe materials are not recommended for correcting Fe deficiencies.

------------------------

Boron (B)

5-60 ppm

Deficiency is unlikely, however, toxicity is possible with some sources of irrigation water, particularly along the coastal areas. Boron content of irrigation water should be less than 0.5 ppm to guard against the possible development of toxic soil levels.

------------------------

Copper (Cu)

5-20 ppm

Deficiency is not likely to occur.

------------------------

Zinc (Zn)

15-50 ppm

Deficiencies are not common on turfgrasses unless grown under alkaline soil conditions. In some cases low Zn levels will be detected in grass grown on soils that are excessively high in P or when grown on compacted-waterlogged soils. Deficiency symptoms do not show up unless the Zn content is less than 10 ppm. Zinc deficiencies can be corrected with foliar applications of zinc sulfate or zinc chelate at the rate of 1/2 ounce per gallon of water per 1000 sq. ft. =====================================================

Crop: WHEAT

Plant Part and Time:

All the above ground portion at growth stages 3-10; or Flag leaf at growth stage 10 (boot stage).

-------------------------

Nitrogen (N)

Whole plant

GS 3 4.00-5.00%

GS 4-6 3.50-4.50%

GS 7-8 3.00-4.00%

GS 9-10 2.50-3.50%

Flag leaf

GS 10 3.50-4.50%

Deficiency due to inadequate N fertilization, excessive rainfall, and/or ineffective N application. If N is low in the tissue topdress with 30 to 60 lbs. N/A. Nitrogen applications should be made before GS 7. Excessive leaf N concentrations can result in induced S deficiency, poor seed set and kernel fill. It appears that the most critical period for determining N and its effect on yield is GS at 4-6.

------------------------

Phosphorus (P)

Whole plant

GS 3-5 0.40-0.70%

GS 6-10 0.20-0.40%

Flag leaf

GS 10 0.30-0.50%

Less than sufficient due to low soil P and/or inadequate P fertilization. Low pH and cool soil temperatures may also reduce P uptake. Soil test and follow soil test recommendations of future plantings. No corrective treatment is recommended for current crop.

------------------------

Potassium (K)

Whole Plant

GS 3-4 3.20-4.00%

GS 5-8 2.00-3.50%

GS 9-10 1.80-3.00%

Flag leaf

GS 10 2.00-3.00%

Less than sufficient due to low soil K and/or inadequate K fertilization. If low levels are detected at early growth stages apply 50-60 lbs. K2O/A by ground rig or 30 lbs K2O/A through the irrigation system. Corrective treatment is not recommended past GS 7. For succeeding crops soil test and apply K2O based on soil test recommendations.

------------------------

Calcium (Ca)

Whole Plant

GS 3-10 0.20-0.50%

Flag leaf

GS 10 0.30-0.50%

Deficiency not likely to occur except on low pH soils.

------------------------

Magnesium (Mg)

Whole plant

GS 3-10 0.15-0.50%

Flag leaf

GS 10 0.20-0.60%

Deficiency due to low soil pH (less than 5.4) and/or low soil Mg. If Mg is low in the tissue 25 lbs Mg/A using a soluble source of Mg. Magnesium deficiency is not likely to occur on soils maintained at the proper soil pH. For succeeding crops soil test and apply dolomitic limestone to correct soil acidity and low soil Mg.

------------------------

Sulfur (S)

Whole plant

GS 3 0.22-0.55%

GS 4-6 0.19-0.55%

GS 7-8 0.17-0.55%

GS 9-10 0.15-0.40%

Flag leaf

GS 10 0.19-0.55%

Low sulfur is a common occurrence on coarse textured low organic matter Coastal Plain soils where S- free fertilizers have been used for an extended period. Sulfur deficiencies may occur due to low soil S and/or when the N:S ratio exceeds 18:1. For optimum growth maintain the N:S ratio between 9:1 and 18:1. If low S is detected prior to application of topdress N include 10 lbs S/A with the topdressing. If topdress N has been applied, apply a foliar application of S using 10 lbs of ammonium sulfate or 1/2 to 1 gallon of ammonium thiosulfate in 30 gallons of water/A. NOTE: Some foliar burn may occur with the latter material.

------------------------

Manganese (Mn)

35-475 ppm

Deficiency may occur on Coastal Plain soils that are coarse textured, low in organic matter and that have been limed to a pH greater than 6.3. If Mn is low apply a foliar application of Mn using 0.50 lb of Mn/A as manganese sulfate or 0.25 lb Mn/A as manganese chelate in 20-25 gallons of water. If deficiency symptoms exist repeat the application in approximately 10 days. If Mn in the tissue is near 5 ppm, plants may not recover after treatment. High Mn is due to low soil pH and levels of 400 to 500 ppm are toxic. For succeeding crops, soil test and apply limestone according to soil test recommendations.

------------------------

Iron (Fe)

25-100 ppm

Deficiency not likely to occur.

------------------------

Boron (B)

3-20 ppm

Deficiency not likely to occur. If deficiency is detected apply a foliar application of B at the rate of 0.2 lb. B/A in 20-25 gallons of water.

------------------------

Copper (Cu)

5-25 ppm

Small grains are sensitive to low Cu; however, deficiency is not likely to occur unless soils are sandy, near neutral in pH and high in organic matter. If Cu is low, apply a foliar application at the rate of 0.25 lb. Cu/A as copper chelate or as a liquid Cu formulation in 20 to 25 gallons of water. Caution: Use of copper sulfate to supply the recommended amount of Cu will result in foliage burn.

------------------------

Zinc (Zn)

15-70 ppm

Deficiency not likely to occur except on coarse textured sandy soils low in Zn and having a pH of 6.5 or higher. If zinc is low, in the tissue, apply a foliar application of Zn using 0.5 lb Zn/A as zinc sulfate or zinc chelate in 20-25 gallons of water. Extreme cold weather will substantially lower the Zn level in tissue, however, as soil temperatures warm, the Zn level in the tissue will increase to within the sufficiency range.

------------------------

Aluminum (Al)

0-200 ppm

High Al concentrations due to very low soil pH or water-logged soils. If Fe is also high, then high Al is due to soil and dust contamination. For an accurate Al or Fe assessment, leaves must be washed (See section on washing samples to remove contaminates.) =====================================================