Utilizing Plant Tissue Testing & Application Methods to Maximize Fertilizer Efficiency Steve Orloff, Dan Putnam, and Rob Wilson UC Cooperative Extension Support from DANR Laboratory and International Plant Nutrition Institute 1
Favorite Quote Last time I fertilized there was a government subsidy program to help pay for the fertilizer. At that time I wasn t sure it was worth it because when we fertilized, I had to spend so much more for baling wire 2
Retail Price of 11-52 52-0 (Over Last 6 Years) $ per ton 1600 1400 1200 1000 800 600 400 200 0 Sep-02 Feb-03 Jan-04 Mar-04 May-05 Oct-05 Feb-06 Oct-06 Feb-07 Dec-07 Feb-08 8-Aug Jul-09 3
Questions 1. Does it pay to fertilize alfalfa with $1,200 a ton 11-52-0? 2. Is banding more efficient than broadcasting phosphorus in established alfalfa? 3. Is it better to apply phosphorus over the winter or late in the season when the P might be running out? 4. Which is more accurate soil or plant tissue analysis? 5. Can cored-baled samples be used instead of fractionated stem samples and which one is better? 6. Which cutting is the preferred cutting to analyze? 7. Is there room for improvement with current fertilization practices? 8. UC critical levels for soil and plant tissue are lower than what many labs and consultants use. Which is correct? 4
Questions 1. Does it pay to fertilize alfalfa with $1,200 a ton 11-52-0? 5
Seasonal yield increase needed to cover cost of a 100 lb/acre P 2 O 5 application at three price levels of 11-52-0 Yield Required (tons/a) 1.4 1.2 1 0.8 0.6 0.4 0.2 0 50 100 150 200 250 300 350 Hay Price ($/ton) $400/T $800/T $1200/T Fertilization application cost of $10 /A assumed 6
Seasonal yield increase needed to cover the cost of an application of 11-52-0 at three price levels (Hay @ $200/ton) Yield Required (tons/a) 1.4 1.2 1 0.8 0.6 0.4 0.2 0 $400/T $800/T $1200/T 0 50 100 150 200 250 Application Rate (lbs P 2 O 5 /A) Fertilization application cost of $10 /A assumed 7
The effect of phosphorus rate and source on alfalfa yield, Lancaster CA. Lbs P 2 O 5 /A Unfertilized 100 Increase 200 Increase Cut 1 4/30 1.56 1.90 0.34 1.94 0.38 Cut 2 6/10 1.65 1.84 0.19 1.85 0.20 Yield (tons/a) Cut 3 7/14 1.57 1.71 0.14 1.76 0.19 Cut 4 8/21 1.60 1.74 0.14 1.75 0.15 Cut 5 10/2 1.13 1.19 0.06 1.27 0.14 Total 7.51 8.38 0.87 8.57 1.06 8
Fertilizer Application Method Research 1) Broadcast application of granular 11-52-0 to the soil surface; 2) Banded application of 11-52-0 below the soil surface using a drill; 3) Banded application of 10-34-0 to the soil surface using TeeJet StreamJet 9
Lassen County Sites ph of 7.3 and an Olsen P 10.1 ppm ph of 7.7 and an Olsen P 17.3 ppm Siskiyou County Sites ph of 7.4 and an Olsen P 2.4 ppm ph of 6.7? and an Olsen P 8.4 ppm 10
The effect of phosphorus rate on alfalfa yield Scott Valley, CA. (Olsen P 2.4 ppm) Rate (lbs P 2 O 5 /A) Untreated 40 80 120 160 Cut 1 6/12 1.94 2.25 2.43 2.68 2.61 Cut 2 7/21 1.44 1.79 1.75 1.79 1.81 Cut 3 8/28 1.25 1.49 1.39 1.46 1.46 Total 4.63 5.53 5.56 5.93 5.88 Increase over Unfert. 0.90 0.93 1.30 1.25 11
The effect of phosphorus rate on alfalfa yield Rate (lbs P 2 O 5 /A) Untreated 40 80 120 160 Butte Valley, CA. (Olsen P 8.4 ppm) Cut 1 6/19 2.39 2.68 2.89 2.98 2.88 Cut 2 7/24 1.83 1.93 2.03 2.10 2.03 Cut 3 8/29 1.33 1.35 1.48 1.50 1.46 Total 5.56 5.96 6.41 6.63 6.37 Increase over unfert. 0.40 0.85 1.07 0.81 12
Can you expect this kind of increase in yield in every alfalfa field? 13
Diagnosing Nutrient Status of Alfalfa Field Visual Observation Soil Testing Plant Tissue Testing Fertilizer Strips 14
Deficiency Symptoms 15
Nutrient Deficiency Symptoms in Alfalfa Nutrient Deficiency Symptoms Nitrogen Phosphorus Potassium Sulfur Generally yellow, stunted plants. Stunted plants with small leaves; sometimes leaves are dark blue-green. Pinhead-sized yellow or white spots on margins of leaves: on more mature leaves, yellow turning to brown leaf tips and edges. Generally yellow, stunted plants. Molybdenum Generally yellow, stunted plants. 16
Nutrient Deficiency Symptoms in Alfalfa Nutrient Deficiency Symptoms Nitrogen Phosphorus Potassium Sulfur Molybdenum Generally yellow, stunted plants. Stunted plants with small leaves; sometimes leaves are dark blue-green. Pinhead-sized yellow or white spots on margins of leaves: on more mature leaves, yellow turning to brown leaf tips and edges. Generally yellow, stunted plants. Generally yellow, stunted plants. 17
Diagnosing Nutrient Deficiencies in Alfalfa Visual Observation Soil Testing 18
NUTRIENT Phosphorus Potassium ammon.acetate Potassium Sulfuric acid Boron Soil Test Interpretation DEFICIENT <5 <40 <300 <0.1 SOIL VALUE (PPM) MARGINAL 5-10 40-80 300-500 0.1-0.2 10-20 ADEQUATE 80-125 500-800 0.2-0.4 HIGH >20 >125 >800 >0.4 19
Relative Reliability of Soil and Plant Tissue Tests Nutrient Symbol Soil Testing Plant Tissue Phosphorus P Good Excellent Potassium K Good Excellent Sulfur S Very Poor Excellent Boron B Poor* Excellent Molybdenum Mo Not Done Excellent *Good for evaluating toxicity of boron How many growers currently do soil tests? Plant tissue tests? 20
Traditional UC Recommended Plant Tissue Testing 21
Boron Interpretation of Test Results for Alfalfa Plant Tissue Samples Taken at 1/10 th Bloom Nutrient Phosphorus (PO 4 -P) Potassium Sulfur (SO 4 -S) Molybdenum Plant Part Mid 3 rd stems Mid 3 rd stems Mid 3 rd leaves Top 3 rd Top 3 rd Unit ppm % ppm ppm ppm Deficient 300-500 0.40-0.65 0-400 Under 15 Under 0.3 Plant Tissue Value a Marginal 500-800 0.65-0.80 400-800 15-20 0.3-1.0 Adequate 800-1500 0.80-1.5 800-1000 20-40 1-5 Over 1500 Over 1.5 Over 1000 Over 200 5-10 High a) Phosphorus concentration should be higher if alfalfa is cut at bud stage, 1200 ppm at mid bud, and even higher, 1600 ppm, if cut at very early bud stage. Other nutrient concentrations should be approximately 10% higher than when sampled at the 1/10 th bloom growth stage (multiply tabular values by 1.10). 22
Recommended Phosphorus and Potassium Application Rates Based on Results of Soil or Plant Tissue Tests Nutrient Phosphorus (P 2 O 5 ) Potassium (K 2 O) Yield Level (ton/acre) 4 8 4 8 Soil or Plant Tissue Test Result Deficient 60-90 120-180 100-200 300-400 Marginal Application Rate, lb/acre 30-45 60-90 50-100 150-200 Adequate 0-20 0-45 0-50 0-100 23
Alternative Tissue Testing Technique Analyze Cored Bale Samples? Drawbacks to Current System Time to collect samples Must be taken prior to cutting Fractionating samples somewhat laborious Difficult to get representative sample 24
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Two samples collected from area of each swath One fractionated and one left as whole tops 26
Bales from each windrow cored before removed from field 27
Soil samples taken along each windrow (15 to 20 cores) Compare results from fractionated tops, whole tops, cored bales, soil samples 28
High Average of 117 samples over 2 years Siskiyou and Lassen Counties Average Deficient Marginal Adequate ph 7.2 Olsen P ppm 17.1 <5 5 10 10 20 >20 Soil K ppm 192 <40 40-80 80-125 >125 29
High Average of 117 samples over 2 years Siskiyou and Lassen Counties Average Deficient Marginal Adequate PO 4 -P ppm 1327 300 500 500 800 800 1500 >1500 Mid-Stems K % 2.03 0.4 0.65 0.65 0.80 0.80 1.50 >1.50 Mid-Stem Leaves SO 4 -S ppm 2390 0 400 400-800 800 1000 >1000 30
High Low High Average of 117 samples over 2 years Siskiyou and Lassen Counties Average Deficient Marginal Adequate ph 7.2 5.6 8.1 Olsen P ppm 17.1 <5 5 10 10 20 >20 2.0 74.7 Soil K ppm 192 <40 40-80 80-125 >125 25 632 31
High Low High Average of 117 samples over 2 years Siskiyou and Lassen Counties Average Deficient Marginal Adequate PO 4 -P ppm 1327 300 500 500 800 800 1500 >1500 230 2220 Mid-Stems K % 2.03 0.4 0.65 0.65 0.80 0.80 1.50 >1.50 0.74 4.18 Mid-Stem Leaves SO 4 -S ppm 2390 0 400 400-800 800 1000 >1000 180 5350 32
Mid-Stem PO 4 -P P vs. Bale Total P Bale (Total P) 0.35 0.30 0.25 0.20 0.15 0.10 y = 0.0001x + 0.097 R 2 = 0.8764 0 200 400 600 800 1000 1200 1400 1600 1800 2000 Mid Stem P04-P (ppm) 33
Concern over leaf loss 34
Whole Plant vs. Bale P Bale P (ppm) 0.350 0.300 0.250 0.200 0.150 0.100 y = 1.0655x - 0.0162 R 2 = 0.9497 0.100 0.150 0.200 0.250 0.300 0.350 Whole Plant P (ppm) 35
Bale vs. Mid Stem K Bale K 4.00 3.50 3.00 2.50 2.00 y = 0.8726x + 0.2373 1.50 R 2 = 0.8316 1.00 0.50 0.00 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 MidStem K 36
Bale K 4.00 3.50 3.00 2.50 2.00 1.50 1.00 0.50 Whole Plant vs. Bale K y = 1.0331x - 0.105 R 2 = 0.9431 0.00 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 Whole Plant K 37
Mid Stem Leaf SO4-S vs Bale S Bale total S (ppm) 5000 4500 4000 3500 3000 2500 2000 1500 1000 500 0 y = 0.5913x + 1464.9 R 2 = 0.7271 0 1000 2000 3000 4000 5000 6000 Mid-Stem Leaf SO4-S (ppm) 38
Phosphorus application rate studies to determine the effect of maturity and cutting on whole tops and mid stem phosphorus levels 39
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Alfalfa Phosphorus Concentration in Midstems Figure 4. Alfalfa phosphorus concentration change during Change during First Harvest for 0, 30, 60, 90, and 150 first harvest growth for the 0, 15, 29, 44 and 73 kg P ha -1 lb/a rate rate treatments. Site #2--2006 Midstem PO 4 -P, mg kg -1 2400 2000 1600 1200 800 400 0 - P 30 - P 60 - P 90 - P 150 - P Adequate PO 4 -P 4 6 8 10 12 14 16 18 20 22 24 First bud Mid bud 10% Days, 0 = June 1 Bloom Yield Mg ha -1 6.88 5.91 5.67 5.78 4.79 41
Alfalfa Total Phosphorus Concentration in Whole Tops Change Figure during 5. First Alfalfa Harvest phosphorus for 0, concentration 30, 60, 90, change and 150 during lb/a rate first harvest growth for the 0, 15, 29, 44 and 73 kg P ha -1 rate treatments. Site #2--2006 Whole plant total P, g kg -1 3.4 3.2 3.0 2.8 2.6 2.4 2.2 2.0 1.8 1.6 0 - P 30 - P 60 - P 90 - P 150 - P Adequate P 1.4 4 6 8 10 12 14 16 18 20 22 24 First bud Mid bud 10% Days, 0 = June 1 Bloom Yield Mg ha -1 6.88 5.91 5.67 5.78 4.79 42
Effect of Maturity on P04 (Mid-stem Cut 1- Scott Valley, 2007)) Mid Stem PO4 (ppm) 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 5/8 5/13 5/18 5/23 5/28 6/2 6/7 6/12 6/17 Date 0 30 60 90 120 150 180 210 43
Mid Stem PO4 (ppm) 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 Effect of Maturity and Cutting on Mid-Stem PO 4 -P 0 30 60 90 120 150 180 210 Mid Stem PO4 (ppm) 3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200 0 5/8 5/13 5/18 5/23 5/28 6/2 6/7 6/12 7/9 6/17 7/11 7/13 7/15 7/17 7/19 7/21 7/23 7/25 Date 1 st Cut 2 nd Cut Date 44
Interpretation of Alfalfa Plant Tissue Samples Taken at 1/10 th Bloom for Whole Plant Samples Collected from Baled Hay Nutrient Phosphorus Potassium Sulfur Unit % % % Deficient <0.20 <0.80 <0.20 Plant Tissue Value a Marginal 0.21-0.22 0.81-1.09 0.20-0.22 Adequate 0.23-0.30 1.10-1.40 0.23-0.30 High >0.30 1.40-3.00 >0.40 a) Phosphorus concentration should be higher if alfalfa is cut at bud stage, 0.26% at mid bud, and even higher, 0.28% if cut at very early bud stage. Other nutrient concentrations should be approximately 10% higher than when sampled at the 1/10 th bloom growth stage (multiply tabular values by 1.10). 45
UC critical levels for soil and plant tissue sometimes lower than what many labs and consultants use. Some labs (mostly out of state use unreasonable numbers) May get an economic yield response slightly above UC values Field variability and composite samples 1735, 1380, 1320, 1180, 985 (mean = 1320) Solution??? 46
% Yield 100 80 60 40 20 0 Potential Yield Increase from Fertilizer Application Very Low Low Medium High Very High Soil or Tissue Test Level 47
Questions 1. Is banding more efficient than broadcasting phosphorus in established alfalfa? 2. Is it better to apply phosphorus over the winter or late in the season when the P might be running out? 3. Which is more accurate soil or plant tissue analysis? 4. Can cored-baled samples be used instead of fractionated stem samples and which one is better? 5. Which cutting is the preferred cutting to analyze? 6. Is there room for improvement with current fertilization practices? 7. UC critical levels for soil and plant tissue are lower than what many labs and consultants use. Which is correct? 8. Does it pay to fertilize alfalfa with over $1,200 a ton 11-52-0? 48