1. 300 Bushel Corn is Easy in No-Till Chad Lee, Ph.D. Extension Agronomist University of Kentucky email: cdlee2@uky.edu website: www.uky.edu/Ag/GrainCrops/ 1 Chad Lee, University of Kentucky ©, 2009-2011

2. 2 Photo taken by Chris Breeze, downloaded from Flickr

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14. 300 bushels in no-tillage, Irrigated Chad Lee, University of Kentucky ©, 2009-2011 14 Joel Armistead, Logan County, Kentucky, 2008: 305.91 bu/acre

15. NameArmistead Farms, 2008 Yield, Bu/A305.91 HybridDeKalb DKC66-23 CountyLogan County Planting Date4/17 Row Width, inches30 Seeding Rate36,000 Final Stand35,000 Prev. CropSoybean P2O5P2O5 58 K2OK2O52 N251 Split NNo, Pre Only OtherMg 7lbs, S 2.5 lbs, B 4 lbs, Zn 2.25 lbs Seed TreatmentPoncho 250 HerbicidesSimazine, Phenoxy, Roundup, Degree InsecticidesHero FungicidesHeadline TillageNo-Till PlanterKinze 2600 HarvesterCAT Lexion 570R Chad Lee, University of Kentucky ©, 2009-2011 15

16. NameArmistead Farms, 2008 Yield, Bu/A305.91 HybridDeKalb DKC66-23 CountyLogan County Planting Date4/17 Row Width, inches30 Seeding Rate36,000 Final Stand35,000 Prev. CropSoybean P2O5P2O5 58 K2OK2O52 N251 Split NNo, Pre Only OtherMg 7lbs, S 2.5 lbs, B 4 lbs, Zn 2.25 lbs Seed TreatmentPoncho 250 HerbicidesSimazine, Phenoxy, Roundup, Degree InsecticidesHero FungicidesHeadline TillageNo-Till PlanterKinze 2600 HarvesterCAT Lexion 570R Chad Lee, University of Kentucky ©, 2009-2011 16 251.00lbs N/A 305.91Bu/A 0.82lbs fert. N/bu N Uptake, grain 0.7 lbs/bu 215 lbs N/acre

17. 300 bushels in no-till, rainfed Chad Lee, University of Kentucky ©, 2009-2011 17 2009, Spindletop Farm 4 hybrids: DKC63-42, DKC63-45, DKC64-44 & DKC65-47 No-Till Loradale Silt Loam

18. Chad Lee, University of Kentucky ©, 2009-2011 18 NameSpindletop Farm, 2009 Yield, Bu/A315.00 HybridDeKalb DKC63-24, DKC63-45, DKC65-44, DKC65-47 CountyFayette County Planting Date4/27 Row Width, inches30 Seeding Rate45,000 Final Stand47,000 Prev. CropSoybean P2O5P2O5 0 (adequate soil test) K2OK2O N160 lbs/A Split NNo, Sidedress Only (V5) Othernone Seed TreatmentPoncho 250 HerbicidesLexar + glyphosate fb glyphosate InsecticidesNone FungicidesNone TillageNo-Till PlanterJohn Deere 7200 HarvesterHege Wintersteiger

19. Chad Lee, University of Kentucky ©, 2009-2011 19 NameSpindletop Farm, 2009 Yield, Bu/A315.00 HybridDeKalb DKC63-24, DKC63-45, DKC65-44, DKC65-47 CountyFayette County Planting Date4/27 Row Width, inches30 Seeding Rate45,000 Final Stand47,000 Prev. CropSoybean P2O5P2O5 0 (adequate soil test) K2OK2O N160 lbs/A Split NNo, Sidedress Only (V5) Othernone Seed TreatmentPoncho 250 HerbicidesLexar + glyphosate fb glyphosate InsecticidesNone FungicidesNone TillageNo-Till PlanterJohn Deere 7200 HarvesterHege Wintersteiger 160.00lbs N/A 315.00Bu/A 0.51lbs fert. N/bu N Uptake, grain 0.7 lbs/bu 221 lbs N/acre 2009, 0 N “check” 117 bu/acre 82 lbs N/acre

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21. Chad Lee, University of Kentucky ©, 2009-2011 21 Name Armistead Farms, 2008 Irrigated Spindletop Farm, 2009 Rainfed Yield, Bu/A305.91315.00 HybridDeKalb DKC66-23 DeKalb DKC63-24, DKC63-45, DKC65-44, DKC65-47 CountyLogan CountyFayette County Planting Date4/174/27 Row Width, inches 30 Seeding Rate36,00045,000 Final Stand35,00047,000 Prev. CropSoybean P2O5P2O5 580 (adequate soil test) K2OK2O520 (adequate soil test) N251160 lbs/A Split NNo, Pre OnlyNo, Sidedress Only (V5)

22. Chad Lee, University of Kentucky ©, 2009-2011 22 Name Armistead Farms, 2008 Irrigated Spindletop Farm, 2009 Rainfed Yield, Bu/A305.91315.00 Other Mg 7lbs, S 2.5 lbs, B 4 lbs, Zn 2.25 lbs none Seed Treatment Poncho 250 Herbicides Simazine, Phenoxy, Roundup, Degree Lexar + glyphosate fb glyphosate InsecticidesHeroNone FungicidesHeadlineNone TillageNo-Till PlanterKinze 2600John Deere 7200 HarvesterCAT Lexion 570RHege Wintersteiger

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24. [(Kernels x Rows) x Ears]/Kernel Size = Bu/Acre Chad Lee, University of Kentucky ©, 2009-2011 24

25. [(Kernels x Rows) x Ears]/Kernel Size = Bu/Acre Chad Lee, University of Kentucky ©, 2009-2011 25

26. Critical Points in Ear and Kernel Development Chad Lee, University of Kentucky ©, 2009-2011 26 Growth StageWhat’s Happening V6 to V8Rows per ear and ear length start to be determined V12 to V14 (1 week before R1) Ovules per row (potential kernels) are determined R1 to R6 (Silking to Blacklayer) Actual kernel number and kernel size is determined

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28. Higher Populations = Smaller Plants = More Yields? Chad Lee, University of Kentucky ©, 2009-2011 28 If you are going to push populations, you better have good stalk strength.

29. Question Are you willing to spend $170/acre in seed for 45,000 seeds per acre with a chance of getting 300 bushels? Chad Lee, University of Kentucky ©, 2009-2011 29 $/bagseeds/acre$/acre $300.0035000 $131.25 $300.0045000 $168.75 $ 37.50

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31. Plant-to-Plant Spacing Chad Lee, University of Kentucky ©, 2009-2011 31

32. Question Are you willing to drive 5 mph during planting? Chad Lee, University of Kentucky ©, 2009-2011 32

33. Corn and Temperature Optimum temperature – Near 90 F, if moisture is abundant – Below 80 F, if moisture is limited Stress Temperature – Above 90 F: roots have difficulty taking up water fast enough Chad Lee, University of Kentucky ©, 2009-2011 33 Source: Modern Corn and Soybean Production. 2000. Hoeft, Nafziger, Johnson and Aldrich

34. Question Can you control temperature? Chad Lee, University of Kentucky ©, 2009-2011 34

35. Corn Water Use In the Midwest, corn will use about 20 to 24 inches of water per season Chad Lee, University of Kentucky ©, 2009-2011 35

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37. Grass-based soil In the Midwest, corn will use about 20 to 24 inches of water per season Many grass-based loams can hold 10 to 15 inches of water per season. Soils with restriction layers may hold 5 inches or less. Chad Lee, University of Kentucky ©, 2009-2011 37

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40. Where do you focus, first? Seeding uniformity Seeding rates Row width Hybrid selection N management Foliar Products Chad Lee, University of Kentucky ©, 2009-2011 40

41. Corn Grain Yields Woodford County, Kentucky 2007 Dry Weather During Seed Fill Chad Lee, University of Kentucky ©, 2009-2011 41 Year: 2007 Location: Woodford County Farm Hybrid: SS777RR2YGPL Poncho 1250-treated seed Planting: May 3, 2007

42. Population Effect, Corn Lexington, 2008-2009, 4 Hybrids, VT3 Hybrids and RRCB Hybrids Chad Lee, University of Kentucky ©, 2009-2011 42

43. Population Effect, Corn Lexington, 2008-2009, 4 Hybrids, VT3 Hybrids and RRCB Hybrids Chad Lee, University of Kentucky ©, 2009-2011 43

44. Twin Row Planter Chad Lee, University of Kentucky ©, 2009-2011 44

45. Twin Row Corn, Spindletop Farm, KY, 2009 Chad Lee, University of Kentucky ©, 2009-2011 45 Three hybrids: – DeKalb, 1 hybrid Developed in 30-inch rows – Nidera, 2 hybrids Developed in 20-inch rows

46. Twin Rows, Narrow Rows Lexington, KY, 2009 Chad Lee, University of Kentucky ©, 2009-2011 46 ** Spindletop Farm, Lexington, KY No-Till Following Soybean Loradale silt loam Seeded: 27 Apr 2009 35,000 seeds/A Lexar+Glyphosate PRE, no POST AX820CL and XA1143MG are from Nidera in Argentina (developed in 20-inch rows). DKC62-54 is from Monsanto DeKalb *, **Significantly different from 30-inch rows at 0.10 and 0.05, respectively.

47. Twin Rows Palmer Amaranth Chad Lee, University of Kentucky ©, 2009-2011 47

48. Fulton County, KY, 2009 Note: Heavy population of Palmer amaranth competing with corn. Chad Lee, University of Kentucky ©, 2009-2011 48 Combine Harvest Hand Harvest A6633 A6522A6633A6522 Estimates--------------------- p value ------------------- single, 32K vs twin, 32K0.73900.36910.83570.6220 single, 32K vs twin, 38K0.94200.06060.14420.1684 twin, 32K vs twin, 38K0.74900.24340.10410.3781

49. Twin Rows or Population? Fulton County, KY, 2009 We cannot conclude if row width or population or both affected yield. We can conclude that weeds cause real problems… Chad Lee, University of Kentucky ©, 2009-2011 49

50. AgriGold Study, Madisonville, KY, 2009 Chad Lee, University of Kentucky ©, 2009-2011 50 Madisonville, KY, 2009 Herring Farms AgriGold A6533 Planted: 25-Apr-09 Clay loam soil conventional tillage

51. Chad Lee, University of Kentucky ©, 2009-2011 51 Pioneer, 2010, Iowa, 2 Locations, 20 Hybrids, 30 vs. twin at 36 and 42K seeds/A.

52. Narrow Row Corn, KY, 2010 Yields were 90 to 110 bu/acre No difference between row widths. Water was the limiting factor. Chad Lee, University of Kentucky ©, 2009-2011 52

53. Corn Row Widths, United States Chad Lee, University of Kentucky ©, 2009-2011 53

54. Down the Road Seeding rates (and final populations) will increase over time. At some point, narrow rows will make more sense. Chad Lee, University of Kentucky ©, 2009-2011 54 Row Spacing (in)Plants / Acre Inches Between Plants 3050,0004.2 2050,0006.3 1550,0008.4

55. What about Nitrogen? Chad Lee, University of Kentucky ©, 2009-2011 55 160.00lbs N/A 315.00Bu/A 0.51lbs fert. N/bu 251.00lbs N/A 305.91Bu/A 0.82lbs fert. N/bu

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57. Nitrogen Use Boundary Condition All N applied is taken up by the plant. No additional N from the soil, atmosphere, etc. N applied = N removed 0.7 lbs N / bushel of corn Real World Fertilizer N is applied. Some N is lost. Soil makes some N available. Chad Lee, University of Kentucky ©, 2009-2011 57

58. MRTN – Maximum Return to N Corn Nitrogen Removal = 0.7 lb per bushel 181/0.7 = 259 bu/acre Profitable range 171-190 lbs N Source: Greg Schwab Iowa Corn following Corn: 89 sites, N at $0.50/lb; corn at $5.60/bu 58 Chad Lee, University of Kentucky ©, 2009-2011

59. MRTN – Maximum Return to N Source: Greg Schwab 59 Chad Lee, University of Kentucky ©, 2009-2011

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61. MRTN – Maximum Return to N Source: Greg Schwab 61 Chad Lee, University of Kentucky ©, 2009-2011 89 sites total

62. MRTN – Maximum Return to N Recommended range 171-190 Using MRTN 89 sites total 21 Sites Within Range What about The Others? Source: Greg Schwab 62 Chad Lee, University of Kentucky ©, 2009-2011

63. Recommended range using 1.2 x Yield (19 lb range) 89 Sites total: 28 Sites Within Range (Old) Illinois Yield Goal Approach Source: Greg Schwab 63 Chad Lee, University of Kentucky ©, 2009-2011

64. Lessons from the N Rate Calculator The MRTN method MIGHT NOT improve efficiency Improvements are possible if you understand the scatter Environment Past N Mgmt Precipitation Placement Drainage Losses Volatilization Immobilization Denitrification Leaching Source: Greg Schwab 64 Chad Lee, University of Kentucky ©, 2009-2011

65. What affects N use/loss? Environment/Management Past N Management Precipitation N Placement Soil drainage Tillage System Losses Volatilization Immobilization Denitrification Leaching Chad Lee, University of Kentucky ©, 2009-2011 65

66. Long-Term No-Till vs Till Plots, Spindletop Farm, Lexington, KY, 1970-2008 Data source: John Grove 66 Chad Lee, University of Kentucky ©, 2009-2011

67. 67 Table 13. Recommended application of nitrogen (lb N/A), corn. Previous CropTillage 1 Soil Drainage Class 2 Well- Drained Moder- ately Well- Drained Poorly Drained Corn, sorghum, soybean, small grain, fallow Intensive 100-140140-175175-200 Conservation 125-165165-200 1 Intensive tillage has less than 30% residue cover, and conservation tillage has more than 30% residue cover on the soil at planting. 2 Soil drainage class examples are given on page 3. AGR-1: Lime and Fertilizer Recommendations If 0.7 lbs N / bu, then max yield is 200 bu/A If 0.8 lbs N / bu, then max yield is 175 bu/A

68. N Management N source N timing N placement Soil Type Soil Condition Weather Tillage History Previous Crop(s) Previous N Management Realistic Yield Goal Chad Lee, University of Kentucky ©, 2009-2011 68 In my Opinion… Fertilizer N Rate

69. Question Are you willing to apply about 240 lbs N/acre in an attempt to reach 300 bu/acre? – Lack of water will reduce yields – High temperatures will reduce yields Chad Lee, University of Kentucky ©, 2009-2011 69

70. Hybrids with greater NUE? Yields have gone up over time. Nitrogen rates have not. Either: – Hybrids are more efficient at using N, or – Hybrids do a better job of taking up N, or – Our application methods are losing less N, or – Some combination of the above Chad Lee, University of Kentucky ©, 2009-2011 70 Each bushel of corn contains about 0.7 lbs of N. Do we want to change this number?

71. Define cheap… $5 per acre $10 per acre $15 per acre Chad Lee, University of Kentucky ©, 2009-2011 71

72. Is this cheap? Soil-Applied Fertilizers KCl about $0.80/lb K 2 O DAP about $0.60/lb P 2 O 5 Foliar Fertilizer 3-18-18, $9.50/gallon – About $2.63 /lb K 2 O – About $2.63/lb P 2 O 5 Chad Lee, University of Kentucky ©, 2009-2011 72 Foliar-applied fertilizers are taken up more readily by the plant. More to the Story… Leaves are not designed to take up large amounts…only a 1 to 2 lbs at a time. You would need multiple foliar applications to do what soil- applied fertilizers and the roots do.

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74. Total uptake of selected nutrients Chad Lee, University of Kentucky ©, 2009-2011 74 CropYieldNPKCaMgSCuMnZn Corn1501649017428 240.111.60.45 Corn30032818034956 480.223.20.90 2 Qt/Acre = 5 lbs/Acre Application Rate NutrientAnalysis2 qt/a10 gal/acre %lbs/A N11%0.5511 P8%0.58 K5%0.255 B0.2%0.010.2 Cu0.05%0.00250.05 Fe0.1%0.0050.1 Mn0.05%0.00250.05 Mo0.005%0.000250.005 Zn0.05%0.00250.05 Greg Schwab

75. High yield system for Corn 1.Productive soils (deep, no compaction) 2.Adequate, timely rainfall (or irrigation) 3.Good genetics (not specific traits) 4.Rotate crops 5.Plant on time (not necessarily early) 6.Adjust pH and fertilize to soil test; adequate N 7.Capture nearly 100% sunlight by about R1 8.Excellent weed control (no trophy-hunting) 9.Scout for diseases & insects 10.Identify limitations and improve those Chad Lee, University of Kentucky ©, 2009-2011 75

76. High Yield Corn? Identify the limitations – In your fields – In your equipment – In your personnel – In your operation Chad Lee, University of Kentucky ©, 2009-2011 76

77. What is your goal? Try to find the next 15 to 20 bushels. Keep targeting that and you may get to 300. Chad Lee, University of Kentucky ©, 2009-2011 77

78. High yield system for Corn 1.Productive soils (deep, no compaction) 2.Adequate, timely rainfall (or irrigation) 3.Good genetics (not specific traits) 4.Rotate crops 5.Plant on time (not necessarily early) 6.Adjust pH and fertilize to soil test; adequate N 7.Capture nearly 100% sunlight by about R1 8.Excellent weed control (no trophy-hunting) 9.Scout for diseases & insects 10.Identify limitations and improve those Chad Lee, University of Kentucky ©, 2009-2011 78

79. Still not happy with your yields? Chad Lee, University of Kentucky ©, 2009-2011 79

80. High Input Protocol for Irrigated Corn Select a good hybrid (work with your seed rep) 45,000 seeds/acre (you choose row spacing) pH, adjusted to soil test P: 120 lbs P 2 O 5 /A above soil test K: 120 lbs K 2 O/A above soil test Zn: 10 lbs/A (about 4 lbs/A if applied with starter) Sulfur: 20 lbs S/A Boron: 1 lb B/A Nitrogen: 240 lbs N/A, or more (can be applied in split applications) Weed control: 6-inch limit on weeds Fungicide at V5 + VT/R1 (tassel/silking) Insecticide: optional Chad Lee, University of Kentucky ©, 2009-2011 80

81. Chad Lee, University of Kentucky ©, 2009-2011 81 High Input Protocol$/acre 45,000 seeds/A $ 37.50 pH, adjusted to soil test P: 120 lbs P 2 O 5 /A above soil test $ 113.00 K: 120 lbs K 2 O/A above soil test $ 54.50 Zn: 10 lbs Zn/A (4lbs/A if applied with starter) $ 34.00 Sulfur: 20 lbs S/A $ 15.00 Boron: 1 lb B/A $ 3.64 N: 240 lbs N/A, or more (can be split applications) $ 24.00 Weed control: prevent summer annuals from getting above 6 inches $ 15.00 Fungicide at V5 and again at VT/R1 (tassel/silking) $ 30.00 Total$ 326.64 Needs replication across fields or farms. $ 326.64 extra per acre

82. If $326.64 / acre is too much… … and you are comfortable spending $5 / acre Chad Lee, University of Kentucky ©, 2009-2011 82

83. Then donate that $5/acre to the university research fund and let us help figure out yield limitations. Chad Lee, University of Kentucky ©, 2009-2011 83 Dr. Peter Thomison The Ohio State University 228 Kottman Hall 2021 Coffey Rd Columbus, OH 43210

84. Thank you for your attention! Chad Lee, University of Kentucky ©, 2009-2011 84

85. TOTAL YIELD Chad Lee, University of Kentucky ©, 2009-2011 85 Yield Limitations TOTAL YIELD Genetics Soils Nutrients Weeds Genetics Soils Nutrients Weeds

86. TOP TEN: 1.Plant early, use seed treatments, hope no late freeze occurs 2.Pick a hybrid/variety with good yield potential…forget about defensive traits. 3.20-inch rows, high populations 4.Correct pH, add more fertilizer & manure (don’t worry about regulations on P) 5.Irrigate at night, absolutely no moisture stress; keep plants cool during day 86 Chad Lee, University of Kentucky ©, 2009-2011 Money is NOT an issue

87. TOP TEN Money is NOT an issue…page 2 6.Keep temps below 70° F at night during flowering, pollination and seed fill 7.Have at least 120 days for growth & development 8.“Spoon feed” N through the irrigation 87 Chad Lee, University of Kentucky ©, 2009-2011

88. TOP TEN Money is NOT an issue…page 3 9.Have very few cloudy days… 10.Keep weeds, diseases and insects out of field…take no prisoners – Weeds: do not let them get above 2 inches – Diseases & Insects: spray every 7 to 10 days from just prior to reproductive development through seed fill 11.Harvest early…about 30% grain moisture 88 Chad Lee, University of Kentucky ©, 2009-2011

89. Argentine corn hybrids have more red in the kernels than North American hybrids. Cattle producers prefer to red tint. Chad Lee, University of Kentucky ©, 2009-2011 89

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92. How can you separate the noise? Look for studies with stats reported. No stats, no predictability. If you do a study… replicate the treatments. Replicates can be: – In the same field – In separate fields – On separate farms We’ll help with the analysis. Chad Lee, University of Kentucky ©, 2009-2011 92

93. A simple “Strip Plot”… Tells how you two treatments did. Without replicates, you have no way to separate performance from the noise. Chad Lee, University of Kentucky ©, 2009-2011 93

94. Chad Lee, University of Kentucky ©, 2009-2011 94 Duvick and Cassman, 1999. Crop Sci 39:1622-1630.

95. Excellent Weed Control Weeds about 6” tall will reduce yields. Allowing weeds to go to seed creates problems for the next year. A soil-applied program following by postemergence applications are usually very good options. Chad Lee, University of Kentucky ©, 2009-2011 95

96. Adequate Fertility Soil test! Every 2 years. 20 acre-increments. University of Kentucky follows economic yield response curve. Other labs use a replacement value. AGR-1 Lime and Fertilizer Recommendations for Kentucky Chad Lee, University of Kentucky ©, 2009-2011 96

97. University of Kentucky Thresholds (AGR-1) CropNutrientSoil Test (lbs/acre) Amount to Apply Corn For GrainP2O5P2O5 >600 K2OK2O>3000 SoybeanP2O5P2O5 >600 K2OK2O>3000 Corn SilageP2O5P2O5 >600 K2OK2O>4200 Chad Lee, University of Kentucky ©, 2009-2011 97

98. Corn Growth Stages V3 3 Collars Nodal roots active. Growing point below ground V6 6 collars Growing point above ground. Tassel and ear development starting. V12 12 collars Ear size, kernel size and kernel number being determined. Limits on water and/or nutrients will reduce yields. 98 Chad Lee, University of Kentucky ©, 2009-2011

99. Corn Growth Stages V15 15 collars Rapid growth, about 10 to 12 days before silking. Most sensitive to stress. VT tassel Last tassel branch is visible but prior to silking. Complete leaf loss will cause nearly 100% yield loss. 99 Chad Lee, University of Kentucky ©, 2009-2011

100. Corn Growth Stages Comparing visible collars to actual nodes. Tassel and ear development start early. 100 Chad Lee, University of Kentucky ©, 2009-2011

101. Corn Growth Stages R1 Silking N and P uptake are rapid. About 50% of total N is taken up after R1. K uptake is nearly complete. Water needed for pollination. Pollination occurs. R2 Blister Ear size nearly complete. Silks begin to dry out. A miniature corn plant is being formed in each fertilized kernel. 101 Chad Lee, University of Kentucky ©, 2009-2011

102. Corn Growth Stages R4 Dough Kernels have accumulated ½ of total dry weight. Five leaves have formed in the kernel. R5 Dent Most kernels have dented and are near 55% moisture at start. Starch layer has formed and progresses down the kernel. 102 Chad Lee, University of Kentucky ©, 2009-2011

103. Corn Growth Stages R6 Physiological Maturity Blacklayer has formed at bottom of kernel. Kernel is about 30 to 35% moisture. 103 Chad Lee, University of Kentucky ©, 2009-2011

104. Corn Growing Degree Days Corn Growing Degree Day Base 50 ° F Max 86 ° F Min 50 ° F Calculate average daily temperature (but not going below 50 for the low or 86 for the high) Example: Daily low of 66 and high of 90 ((66 + 86)/2) – 50 = 26 GDDs No higher than 86

105. Corn Growing Degree Days Corn Growing Degree Day Base 50 ° F Max 86 ° F Min 50 ° F Calculate average daily temperature (but not going below 50 for the low or 86 for the high) Example: – Daily low of 40 and high of 60 – ((50 + 60)/2) – 50 = 5 GDDs No lower than 50

106. Corn Growing Degree Days About 100 to 125 GDDs are required for crop emergence. About 82 GDDs are required for each collar developed after emergence. Example: – 700 GDDs have accumulated since planting. – 700 – 125 = 575 GDDs since emergence – 575/82 = 7 so, the corn should be close to V7 Corn and Soybean Field Guide, 2010 Edition 106 Chad Lee, University of Kentucky ©, 2009-2011

107. Table 1. Normal Range of CEC Values for Common Color/Texture Soil Groups. CEC in Soil GroupsExamplesmeg/100g Light colored sandsPlainfield3 to 5 Bloomfield Dark colored sandsMaumee10 to 20 Gilford Light colored loams and silt loamsClermont-Miami10 to 20 Miami Dark Colored loams and silt loamsSidell15 to 25 Gennessee Dark Colored silty clay loams and silty claysPewamo30 to 40 Hoytville Organic soilsCarlisle muck50 to 100 Source: David Mengel. 1993. AY-238: Fundamentals of Soil Cation Exchange Capacity (CEC). Purdue Univ. Chad Lee, University of Kentucky ©, 2009-2011 107