4R Nutrient Stewardship : New Mexico Specifics. Robert Flynn, Extension Agronomist Extension Plant Sciences

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1 4R Nutrient Stewardship : New Mexico Specifics Robert Flynn, Extension Agronomist Extension Plant Sciences rflynn@nmsu.edu An Educational Program Initiated by the International Plant Nutrition Institute (IPNI)

2 Remember what an agronomist is Agronomist /ə- grän-ə-məst/ noun: One who studies the science of soil management and crop production One who applies the various soil and plant sciences to soil management and crop production; scientific agriculture

3 Or from Greek: Agros (field) and nomos (to manage) The branch of agriculture that treats of the principles and practices of crop production and field management. First started, perhaps, in 1843 in Rothamsted, England to study fertilizer use.

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5 And Continues in the U.S. Ag Science Center - Artesia

6 General Goal oals for Both Horticultura cultural l and Field Crops Turf Attractive Healthy Withstand Rigors of Intended Use Row Crops Chile, Corn, Sorghum, Wheat, others Yield Quality Profitability Pecans Yield Quality Forages & Grains Alfalfa Small grains for silage Small grains for grain

7 Fertilization Contributes to Turf Color Density Uniformity Growth Rate Agronomic Crops Growth Rate Yield Crop Quality End User Nutrition Flour Quality

8 Properly Fertilized Crops Are Better able to compete with weedy species Recover better from stress Environmental Biotic

9 So, I could tell you that you need lb N/A 80 lb P 2 O 5 /A 120 lb K 2 O/A Plus other nutrients However,.

10 But it is NOT all about rate! THE 4 R s Right Source Right Time Right Place Right Rate

11 Liebig s Law of the Minimum

12 Liebig s Law of the Minimum Yield & Performance is Limited by the Nutrient in Least Supply (all other factors water, salinity, pests, environment -held constant)

13 Water is a BIG other factor

14 Alfalfa Yield and Water ALFALFA Alfalfa

15 Chile Yield and Water CHILE Chile

16 Corn for Grain Yield and Water CORN

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21 Uphill side Downhill side Friction losses

22 Soil Type Impacts Crop Response to Irrigation

23 So is Soil Salinity

24 Measured by electrical conductivity (e.c.) RO Reject Water Soft Water Tap Water Spring Water RO Water Distilled Water 0 mmhos/cm Increasing Salinity

25 Threshold g plant Y = EC e R 2 = EC (mmhos cm -1 ) Yield/Performance as a function of EC e

26 Threshold g plant Y = EC e R 2 = EC (mmhos cm -1 ) Yield/Performance as a function of EC e

27 Threshold g plant Y = EC e R 2 = EC (mmhos cm -1 ) Yield/Performance as a function of EC e

28 Thresho hold g plant Y = EC e R 2 = EC (mmhos cm -1 ) Yield/Performance as a function of EC e

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31 1:1 soil:water ok when EC<0.5 mmhos/cm Saturated Paste is Best & Preferred when EC>0.5 mmhos/cm

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34 Salinity & Sodium

35 Sodium Promotes Promotes Dispersion Dispersion No or Reduced Aggregates

36 Sodium Adsorption Ratio [Na + ] SAR = ([Ca 2+ ] + [Mg 2+ ])/2 (concentrations are in mmol/l) High SAR = Unstable Soil Low SAR = Stable Soil

37 Manage Sodium in Soil with Calcium (Gypsum (CaSO4)) Ca ++ SO = 4 Ca ++ Ca Ca ++ Na + Na + Na + Ca ++ Ca Na Na + Na + Na Na + Na + + Na + Na Excess water must be applied!! + Na + Na + Must also be good drainage! K +

38 TIME = 0

39 TIME = 24 hours Gypsum rate determined from soil Exchangeable Sodium Percentage (ESP) and sodium concentration in the soil.

40 Liebig s Law of the Minimum Need to know what you need in order to determine a Source

41 Determined by Soil Sampling Past History

42 Appropriate Tests for NM Soils Saturated paste ph Saturated paste EC Sodium Adsorption Ratio (SAR) SP Organic Matter Nitrate-N or Total Inorganic-N Phosphorus (Olsen) Potassium (Water or Ammonium Acetate) (Guide A146) DTPA Extractable Fe Zn Mn Cu Optional (if already known) Texture Soil Lime %

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44 Sampling is KEY to the 4R progra ogram

45 Be Representative

46 Be Representative!

47 Plant Nutrition Soil testing identifies nutrients needed for productivity Low Moderate Sufficient Excessive

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49 Minerals Required for Plant Growth Turfgrass % Nitrogen Phosphorus Potassium Sulfur Calcium Magnesium Iron

50 Alfalfa Nutrient Content (%) N S P K Mg Ca Na B Zn Mn Fe Cu Al

51 Low Soil Nutrient Moderate Soil Nutrient Sufficient Soil Nutrient

52 N P 2 O 5 K 2 0, others

53 N Credits = Soil Organic Matter SOM also improves micronutrient availability & water holding capacity

54 Legume N Credit

55 Manure Nutrient Credit Average 35 lb Total N/dry ton (8-12 lb available N). NMSU Soil Test Interpretation Workbook will subtract out potential volatilization losses of the NH 4 content De-nitrification (N 2 ) losses depending on soil organic matter levels and soil drainage class Mineralized N from the organic N pool in manure is estimated based on literature or C:N ratio

56 Other Manure Nutrient Credits per Dry Ton Nutrient Phosphorus Potash Calcium Magnesium Iron Credit Zinc Total Salt Pounds per Dry Ton

57 lbs per acre inch Effluent Characteristics Cl P2O5 K2O Na Org. N NH4-N 706 lb total salt per acre inch Fall 2003, n = 48 sampled dairies

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59 But, much of NM s productive land has >3% lime Soil ph as related to soil calcium carbonate

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61 Soil ph = 7.3 Iron = 12 ppm (VH) Free lime = medium (~2%) Choices: Elemental S Ironite Sequestar Fe-EDDHA Fertilome s Chelated (EDTA) Liquid Iron Product

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63 Client results Fertilome & Ironite is a very rich green color. Most successful products. EDDHA had not greened up much

64 Soil ph >7.5 % Lime = 20%

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66 EDDHA Chelate Miller s Ferriplus Some additional N may help the chelate do a better job.

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68 The Chelates Organic Molecules that hold metals like Iron, Zinc, Nickel, etc. Hampene (Fe)EDTA Sequestrene 138 (Fe)DTPA Miller s Ferriplus (Fe)EDDHA

69 Stability and Availability 100 EDDHA EDTA DTPA % Chelate with Fe Soil ph

70 Chelate Effectiveness FeEDDHA FeDTPA FeEDTA Yield (lb/pot) Fe added (ppm)

71 Remember Using problems like iron deficiency is an opportunity to test different sources of iron. Not only for effectiveness but for cost. Milorganite? Composted WWTP solids?

72 Nutrient Sources Incomplete Complete Solids Liquids Quick Release Slow Release Includes organics

73 Quick Release N Fertilizers Carri rrier Grade % N Residual Response Burn Potential Leaching Potential UREA short High Moderate Ammonium sulfate Potassium nitrate short High High short High High

74 Slow Release N Fertilizers Carrie ier Grade % N Residual Response Burn Potential Leachin hing Potential IBDU Variable Variable 24 Moderate Moderate Low Low Sulfur Coated Moderate Low Low Urea Resin-coated to 13 Mod to Low Low Long Methylene coated and ureaformaldehyde Mod to Long Low Low IBDU = isobutylidene diurea

75 Nitrogen can be volatilized Especially in high ph soils Some products have been demonstrated to lower volatilization rate Agrotain on urea if not able to irrigate in Or be sure to irrigate in with at least 3/10 to ½ of water immediately after application.

76 Nitrogen Carriers Ammonium Sulfate (NH 4+ ) Urea (CH 4 N 2 O) UAN (Urea Ammonium Nitrate) Calcium Nitrate (Ca(NO 3 ) 2 ) Ammonium Nitrate (NH 4 NO 3 ) Organic Sources through Mineralization

77 Beware of Volatilization / Leaching Ammonium containing fertilizers subject to volatilization losses. Additives may reduce volatility (eg. Agrotain) Nitrate containing fertilizers subject to leaching with too much applied water. ppm NO 3 -N

78 The 4 R s Right Source Right Time Right Place Right Rate

79 TIMING OF N APPLICATION Example: Apples N uptake by apple roots begins about 3 weeks after bud-break. BUT Soil Temperature also affects uptake Soil Temps 54 o F to 68 o F enable tree to take up more N 1/3 N remains in roots 2/3 N moved to shank, stem, and new growth

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81 Timing Important for Irrigated Fields Flood/Furrow Irrigated Fields No Effluent or Manure With Effluent or Manure

82 Pivot Irrigated Fields No Effluent or Manure With Effluent or Manure

83 Leaching

84 Timing Applications small grains example

85 Timing Applications

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87 Strawberry before EDDHA application Wendy Brunswick Chandler Allstar Strawberry after EDDHA

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89 The 4 R s Right Source Right Time Right Place Right Rate

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92 Definitions

93 Starter Fertilizer Configurations 2x2 Starter Pop-up or Drill row Direct seed contact Dribble Surface Band Seed Seed Seed Fertilizer Fertilizer Fertilizer

94 The 4 R s Right Source Right Time Right Place Right Rate

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96 N P 2 O 5 K 2 0, others

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98 Determining Organic Source Rate Total N C:N PAN (% of Total N) % of DW 28 d Season Verify C:N Ratio Season = 125 days 2200 GDD (0 o C base) : Chicken Composts similar to uncomposted 4% N material Uncomposted Materials 1 35 < < < < Composts Dan Sullivan, OSU

99 Measured Data %PAN & Total %N %PAN day PAN Full-season PAN Total %N

100 Smoothed data

101 When low soil nutrients Cool Season Grasses Grass lb N/1000 sq ft Tall fescue 2-4 Perennial ryegrass 2-4 Creeping bentgrass 3-8

102 When low soil nutrients Warm Season Turf Grass Improved bermudagrass Buffalograss St. Augustinegrass zoysiagrass lb N/1000 sq ft

103 4R Nutrient Stewardship Biodiversity Resource use efficiencies: Energy, Labor, Nutrient, Water Soil erosion CROPPING SYSTEM OBJECTIVES Healthy environment Nutrient loss Water & air quality Adoption Nutrient balance Yield Net profit Soil productivity Ecosystems services Productivity Durability Farm income Profitability Return on Quality Working investment Yield conditions stability