NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000...

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NITROGEN

Transcript of NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000...

Page 1: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

NITROGEN

Page 2: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen• Air

– 78% Nitrogen– 35,000 Tons/Acre– Unavailable Form

• Nitrogen Fertilization– Required in largest quantities (2-6% in plants)– Most frequently deficient nutrient– Main environmental concern is leaching to groundwater

• Forms Used by plants as– NO3

- Nitrate– NH4

+ Ammonium

Page 3: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Functions of N in Plants

• Constituent of – Proteins (6.25 x %N for crops other than wheat)

(5.7x%N for wheat) – Chlorophyll– Enzymes and other compounds

• Necessary for respiration, growth and reproduction• Increased grain and forage yield of nonlegumes• Improved root growth and H2O use efficiency

Page 4: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Grain Sorghum

Grain Sorghum N Uptake

Page 5: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

20%

40%

60%

80%

100%

V 6 Tassel MaturityStage Of Growth

% o

f Tot

al U

ptak

e

Potassium

Phosphorus

Nitrogen

Dry Matter

Corn Nutrient Uptake And Dry Matter Accumulation

Page 6: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nutrient Deficiency Symptoms

• Pale green - yellow coloration. Starts at leaf tip & down midrib.

• Slow growth, stunted plants

• Mobile - starts on lower leaves

• Reduced tillering

• Low Protein

Page 7: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 8: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 9: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

N Deficiency in Legumes

• Check roots for active nodules

Page 10: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen Cycle

Animal Manures

Soil OrganicMatter

Crop Residues

Plant Uptake NO3-

Nitrate

NH4+

Ammonium

Legume Fixation of

Atmospheric N2

Fertilizer Nitrogen

Nitrogen Fixation by Lightning

Ammonia Loss Through

Leaves

Immobilization

Immobilization (By Crop Residues)

Removed by Harvest

Removed by Denitrification (Gaseous Loss from Wet Soils

Removed by Leaching

(Ammonification)

(Nitr

ifica

tion)

Mineralization

Page 11: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen Cycle - Rainfall

• 3 to 10 lb N per Acre per year

• Unimportant over the short term, but very important over hundreds of thousands of years.

• Most deposited in summer with thunderstorms, very little in snow

Page 12: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Mineralization• Soil Organic Matter

Source of most soil N5% N, 1-3% released annually• 10-30 pounds N per year per 1% Organic MatterRate of release affected by:• Tillage • Temperature• Moisture• Past N inputs

Page 13: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Soil Organic Matter (SOM) AssumptionsWeight of Plow Layer (6-7”) of Soil equals 2,000,000 lb/acre1% SOM x 2,000,000 = 20,000 lbs SOM/a About 67% of residue carbon is lost as microbial CO2

About 1-3 % of SOM is decomposed each yearAssume soil organic matter is 5% N and 59% C

Soil Organic Matter N ContributionsFor soil with 1% SOM20,000 lb SOM x 5% N = 1,000 lbs N/A1, 000 x 2% Mineralized/yr = 20 lbs N/A/yr mineralized

Page 14: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

25

30

35

40

45

50

55

60

65

1-Nov

8-Nov

15-N

ov

22-N

ov

29-N

ov

6-Dec

Date

Soil

Tem

p (F

)Clay Center Research Station,

Soil Temp @4 inches

Daily average Temp. 2001

15 year average

Page 15: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

LEGUMES

• Alfalfa, clover, beans, etc.• Symbiotic relationship with

Rhizobium bacteria• Plant provides energy

(carbohydrate)• Bacteria synthesize N2 to

NH4

Symbiotic Fixation

Page 16: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Legume Crop N CreditsNitrogen Credit (lb N/A)

Previous Crop Warm Season Cool Season**

Alfalfa -Excellent Stand (5 or more plants/ft2)Good Stand (2-4 plants/ft2)Fair Stand (1-2 plants/ft2)Poor Stand (less than 1 plants/ft2)

12080400

6040200

Sweet Clover -Excellent StandGood Stand Poor Stand)

110600

553020

Red Clover -Excellent StandGood Stand Poor Stand)

80400

40200

Soybeans 40 0

•N credits in no-till systems may be less.•Cool season crops include winter small grains which grow in cool months of the year. •Warm season crops include corn, sorghums, sunflowers and others which grow in summer

Page 17: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Manure

• Highly variable nutrient content

• Year of application nutrient credit– N = 25-90%– P = 50-100%– K > 85%

• NH3 volatilization if unincorporated or applied through pivot

Page 18: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

100%

90%

50%

90%

65%

50%

40%

30%

20%

10%5%

Sweep Injected

Immediate Incorporation

1 Day 2 Days 3 Days 4 Days 5 Days 6 Days 7+ DaysKnife Injected

Sprinkler Irrigation

Time Between Broaccast Surface Application and Incorporation

Percent Of Inorganic N Available To Crops For Various Manure Management Systems

Estimated Organic N Available To Crops After Manure Application

Year 1 Year 2 Year 3- - - % Of Original Organic N Available - - -

Liquid Manure 30 12 6Solid Manure 25 12 6Compost 20 6 3

Page 19: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Manure TestResults From X = Plant Available Nutrients

Laboratory( Lb per ton ) ( Lb per ton )

Organic N X 25% Availabile In Year Of Application = Organic N

Ammonium N X Availability Factor From Fig. 1 = Ammonium N

Total N X = Ammonium + Organic N

Total P2O5 X 50% for V. Low - Low P Soil Tests = Available P2O5100% for Medium - V. High Soil Tests

Total K2O X 85% Potassium Efficiency Factor = Available K2O

Nutrient Availability Factor

Sum Of Organic & Ammonium N

Solid Manure Nutrient Crediting Worksheet

Page 20: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Manure TestResults From X = Plant Available Nutrients

Laboratory

( Lb per 1,000 gal ) ( Lb per 1,000 gal )

Organic N X 25% Availabile In Year Of Application = Organic N

Ammonium N X Availability Factor From Fig. 1 = Ammonium N

Total N X = Ammonium + Organic N

Total P2O5 X 50% for V. Low - Low P Soil Tests = Available P2O5

100% for Medium - V. High Soil Tests

Total K2O X 85% Potassium Efficiency Factor = Available K2O

Liquid Manure Nutrient Crediting Worksheet

Nutrient Availability Factor

Sum Of Organic & Ammonium N

Page 21: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Mineralization/Immobilization

Organic N(plant unavailable)

Inorganic N(plant available)

High C:N Ratios

Legume ResiduesManure

Soil Organic Matter

Low C:N Ratios

Corn StalksSorghum StubbleWheat Stubble

Soil Microbes Responsible For Both Conversions

Page 22: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen Immobilization & Mineralization

C:N Ratio of Organic Material Affects Rate of Activity

ImmobilizationResidue with High C:N Ratio

Straw, Cornstalks, Sorghum stubble

Plant available nitrogen tied up

Mineralization

Residue with Low C:N Ratio Alfalfa, Soil Organic Matter, Manure

Plant available nitrogen rreleased

Inorganic N Organic NMineralization

C:N < ~ 25:1

C:N > ~ 25:1

Immobilization

Page 23: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Typical Carbon and Nitrogen Content of Organic Materials

Source

Alfalfa

Soybean Residue

Cornstalks

Small grain straw

Microorganisms

Soil O.M.

Grain Sorghum

Manure

Wood Chips

Glyphosate (Roundup)

% Carbon

40

---

40

40

50

52

40

--

40

-

% Nitrogen

3.0

---

0.7

0.5

6.2

5.0

0.5

--

0.1

-

C:N Ratio

13:1

15:1

60:1

80:1

8:1

10:1

80:1

<20:1

200:1

3:1

Page 24: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonification (N mineralization) and Nitrification

Conversion of Nitrogen into plant-available forms through the microbial processes of ammonification and nitrification.

Soil Organic Matter

Manure

Rotting Plant Residues

+

Ammonification Nitrification

NH4+

Ammonium

NO2-

Nitrite

Oxygen

NO3-

NitrateNitrosomonas

BacteriaNitrobacter

Bacteria

Oxygen

H+

Acidity

Page 25: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect of Temperature on Nitrification Rate

100

80

60

40

20

Rate of Nitrate

Production (% of Max.)

Temperature - Degrees F at 4-inch Depth

032 41 50 68 7759

Page 26: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect of Time on Nitrification

100

80

60

40

20

% Nitrification

Time (Weeks)

032 3 96

75 Degrees F.52 Degrees F.

47 Degrees F.

42 Degrees F.

37 Degrees F.

Page 27: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Influence of Soil Temperature On NitrificationKansas Stae University

0

50

100

150

200

250

300

350

400

450

0 60 120 180 240 300

ppm

NH4

+-N

August October December February April June

August Application(warm soil)

November Application(cool soil)

Kansas State University

Page 28: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

How Nitrogen Fertilizer Affects Soil Acidity

When the nitrification process converts the ammonium ion to nitrate, hydrogen ions are released:

NH4+ + 2O2 NO3

- + 2H+ + H2ONitrifying Bacteria

Ammonium Oxygen Nitrate Hydrogen Water

Page 29: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect of N Sources on Soil pH After 5 Years of Applying 180 lb N/A to a No-till Field

N Source Soil Sample Depth

None 6.5 6.7

Urea 6.2 5.9

UAN 6.2 5.8

Ammonium Sulfate 5.2 4.7

0-7” 0-1”

Page 30: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

What Happens to Nitrate Nitrogen?

• Utilized by plants• Retained in soil as inorganic N• Immobilized to organic N

• Denitrification• Leaching

Page 31: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

N Loss Through Denitrification

NO2-

NONO3

-

N2O

N2

Soil SurfaceEscapes As

Gases

Caused by soil organisms that flourish in the absence of soil oxygen.

Obtain oxygen (O) by from NO3- .

Occurs in warm, saturated. Losses can be severe

Page 32: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Denitrification Losses in Waterlogged Soil - how much can be lost?

• Depends on:– temperature– duration of anerobic

condition– Can be more

significant than leaching loss on non-sandy soil

Page 33: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen Loss from Soil Saturated at Two Temperature Ranges (Univ. Neb.)

Period of Saturation Temperature (°F.) N Loss (%)

5

10

3

5

7

9

55-60

55-60

75-80

75-80

75-80

75-80

10

25

60

75

85

95

Page 34: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 35: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

What Can You Do To Manage Denitrification N Loss ?

• Improve soil drainage

• Delay N application on wet soils

• Nitrification Inhibitor

• Ammonium Containing/Forming N Sources

Page 36: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 37: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonium and Nitrate Ion Mobility• Ammonium (NH4

+) Ions– Positively charged– Attracted to negatively

charged soil colloids– Relatively immobile in soil

• Nitrate (NO3-) Ions

– Negatively charged– Repelled by negatively

charged soil colloids– Move through the soil in

all directions

NO3-

NO3-

NO3-

NO3-

NH4+

NH4+

NH4+

NH4+

NH4+

Nitrogen Leaching

Page 38: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Factors Affecting Nitrogen Leaching

– Sandy soils

– Vertical channels (cracks, wormholes)

– N rate exceeds crop needs

– Improper application timing

– Nitrate N forms

Page 39: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Excessive Irrigation or Precipitation

Groundwater nitrate is a major environmental issue affecting N fertilizer management

Page 40: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Environmental and Health Concerns of NO3

- in Water

• Blue baby (methemoglobinemia)– 10 ppm N03- N standard

• Effect on aquatic life – increased algae growth – oxygen deficiency – Contributes to hypoxia (dead zone) in Gulf of Mexico– Nitrate sources include leaching (tile lines) and N runoff

Page 41: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Volatilization• Loss of gaseous NH3 to atmosphere

can occur from:

Unincorporated Surface applications• Manure• Urea containing materials under specific conditions

Anhydrous ammonia• Poor sealing• Too shallow

Will discuss in detail in urea section

Page 42: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

N Volatilization From Leaves

• NH3 or N oxides

• 30-70 lbs/acre, much is reabsorbed in canopy

• % N recovery by plant may be higher than is often reported (66% to 85%)

• Implication: Crops are more efficient at recovering N than previously thought; thus less is potentially available in soil for leaching.

Page 43: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

(Urea Melt)

Anhydrous Ammonia Plant

CO2

(Carbon dioxide)NH3

Ammonia

82% N

Air

(N2,O2)N H Natural Gas

(CH4)

Urea Melt

N Solution Plant

Water

Ammonium Nitrate Melt

NH4NO3

Ammonium Nitrate

(34% N)

Ammonium Nitrate Plant

HNO3

(Nitric Acid)

Ammonium Nitrate

Melt

UAN

(Urea Ammonium Nitrate)

28-32% N

Prilling Tower

CO (NH2)2

(Urea) 46% N

Urea Plant

Granulator

Heat and Pressure +

Catalyst

Nitrogen

1 Part

Hydrogen

3 Parts

. . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . ..

......................

Nitric Acid Plant

Page 44: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Alternatives to Natural Gas for Ammonia Production

Coke» by-product of oil refinery

used to produce NH3 atCoffeyville, KS

Coal gasification

Page 45: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Anhydrous Ammonia - The Base Material

NH3

NitricAcid

SulfuricAcid

PhosphoricAcid

CarbonDioxide

Urea + A.N. +Water

Ammonium Nitrate

Ammonium Sulfate

Ammonium Phosphate

Urea

Nitrogen Solution

Page 46: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Properties of Ammonia - NH3

N Content 82%

H Content 18%

Weight (lb/Gal) 5.7 at - 28 Degrees F.

5.3 at 32 Degrees F.

5.1 at 60 Degrees F.

4.9 at 100 Degrees F.

Expansion Rate 1 Gal. Liquid = 850 Gal. Vapor

Flammable Limits 16 to 25% by Volume in Air at 1500 ° F.

Specific Gravity [lb/gl] 0.588

Solubility Extremely Water Soluble

Vaporization Point (Boiling Point) -28 Degrees F.

Vapor Pressure at 0 Degrees F. 15.7 psi.

70 Degrees F. 114.1 psi.

100 Degrees F. 197.2 psi.

Page 47: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Handling Anhydrous Ammonia SafelyRemember! NH3 is hazardous because of tremendous affinity for water!

•NH3 Injury

• Dehydrates eyes, lungs and skin tissue

• Treat with water, water, more water!

• Have a shower or water tank at plant and 5 Gal water

container for tanks

• Don’t use salves for 24 hours

• Protect Lungs with a water soaked towel

•AVOID ACCIDENTS

• Work up-wind

• Maintain equipment

• Goggles, gloves, boots, and other equipment

• Instruct farmer users

Page 48: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Proper Sealing of NH3

• How much N loss?

Page 49: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Proper Placement of Ammonia

Ideal Moisture Correct Depth

Sealed at surface NH3

spreads about 4 inches

Some NH3lost at

surface

Slit does not seal, NH3does not penetrate

Ammonia moves too far

Some NH3reaches surface

Too Shallow Too Wet Too Dry or Sandy

Rate Too High For Soil

Page 50: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Recommended Knife Spacings

Crop

Corn, Sorghum

Winter Wheat

Spring Small Grain

Recommended Knife Spacing

(Inches)

30-40

12-18

9-15

Page 51: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect of Spacing of NH3 Knives On Corn Yield

Spacing & Locationof NH3 knife .

Corn Yield(bu/A)

30”, beneath corn row 144

30”, between rows 148

60”, beneath row 149

60”, between rows 145

60”, beneath adjacent rows 139

Page 52: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect of Application Depth and Time of Planting on the Effect of Ammonia Toxicity on Corn Stands

Days Delay in Planting after NH3 Application

0 7 14 0 7 14

60 96 100 35 60 90

100 100 100 80 100 100

100 100 100 100 100 100

200 lb N 400 lb NDepth of

Application

(Inches)

4

7

10

Temporary effects of NH3 : Freezing temperature, High pH, & high affinity for water.

Stand (% of Normal)

Page 53: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonia Effect on Bacteria Population*

Days After Injection Point 1-inch Away 2-inch Away

0 260,000 4,600,000 2,300,000

3 7,200,000 6,400,000 3,000,000

10 8,400,000 5,400,000 2,000,000

*Original Count 2,250,000 bacteria/gm of soil

Bacteria/Gram Dry Soil

pH in injection zone

Page 54: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Earthworm Population After Ammonia ApplicationDeibert and Uttier, North Dakota State University

EarthwormsCocoonsTotal

0 N9862160

Sept. 15

50 N9871

169

Nov. 1

50 N29298

390

Anhydrous Ammonia Application

- - - Earthworms per square yard - - -

Page 55: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Doesn’t Anhydrous make the Soil Hard?

Page 56: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Nitrogen SourceSoil pH

Soil OM Bray P-1 NO3

--N NH4+-N Density

(%) - - - - - ppm - - - - (lb/cu ft)

Check (No N) 6.2 2.0 38 4 5 100Anhydrous Ammonia 5.2 1.8 27 27 9 99

Ammonium Nitrate 5.2 2.3 26 21 11 99Urea 5.1 2.3 24 31 12 99

UAN Solution 5.2 2.0 28 20 8 100

Effect Of 20 Years Of N Fertilizers On Soils (Kansas State University)

78 bu/A for Ammonia. Ammonium Nitrate, Urea, UAN over last 4 years37 bu/A for Check (No N) treatment over last 4 years

Page 57: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Sources of Knife to Knife Variability in Output with NH3 Applicators

• Manifolds– type and setup– Hose barbs

Page 58: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Sources of Knife to Knife Variability in Output with NH3 Applicators

• Hose length and size

• Knife styles, plugging and wear

Page 59: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Sources of Knife to Knife Variability in Output with NH3 Applicators

• Manifolds– type and setup

• Hose length and size• Knife styles, plugging

and wear

Page 60: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonium Nitrate (NH4NO3, 34-0-0)

• Hydrogen 5%• Oxygen 60%• Nitrogen 35%• Bulk Density 48 to 58 lb/cu ft• Critical Relative Humidity 59.4%

Page 61: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonium Nitrate• Advantages

– Not subject to volatilization losses– Contains readily available, mobile nitrate

• Disadvantages– Availability declining in market– Can not ship internationally– Nitrate portion is subject to leaching– Cost of production is higher– More corrosive to metal and concrete– HydroscopicProduction continues to decline

Page 62: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea• Highest analysis dry fertilizer, 46-0-0• Dominates international marketplace• Good physical and handling characteristics• Fewer environmental production problems• Lower cost per pound of N

Potential volatilization lossDo not place in direct seed contact

Page 63: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea Production

Ammonia + Carbon Dioxide

Urea + Water

Energy (production)

Page 64: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea (CO(NH2)2) 46-0-0

• Hydrogen 6.6%• Oxygen 26.7%• Carbon 20%• Nitrogen 46.7%• Bulk Density 45 to 48 lb/cu ft• Critical Relative Humidity 75.2%

Page 65: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Ammonia Volatilization

Ammonia + Carbon Dioxide

Urea + Water

Enzyme (biological)

Page 66: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Factors Affecting Volatilization of Surface Applied Urea

• Unincorporated surface applications• Warm, moist, drying soil conditions• Residues associated with enzyme••• Sandy soils and high soil pH increase potential• No-till grain sorghum probably is most

susceptible (residues, warmer soils)

Page 67: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 68: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Understanding and Managing Urea Containing Fertilizers

Page 69: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

D. Kissel - McInnes, et. al Kansas State University

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Warm, Moist Drying Soils- Not Hot, Dry Conditions

Residue- Urease, Moist Soil Surface

Immobilization Effects

D. Kissel - McInnes, et. al Kansas State University

Page 71: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Laboratory Study

Page 72: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea Volatilization Loss Summary

• Potential for volatilization loss greatly exaggerated

• Amount of loss is also greatly exaggerated

• Need to recognize when volatilization loss may potentially occur

Page 73: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea Volatility

• Only possible with unincorporated surface applications

• Losses vary with environment, are difficult to predict and often exaggerated

• Need to manage urea to minimize potential, ammonium nitrate is not the universal solution

Page 74: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Managing Potential Urea Volatilization

• Small grains and pasture– Summer applications are of a concern– Late fall through early spring performs well

• Row Crops– Incorporation or subsurface banding– Apply early in spring– Surface Band

• No-till or Minimum till– Inject or surface band to improve efficiency– Apply early in spring

Page 75: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea-Ammonium Nitrate Solution (UAN)

Properties of 28% and 32% UAN Solutions

Nitrogen, %

Composition by Weight,

% Ammonium Nitrate

Urea

Water

Salt Out Temperature degrees F.

Density, lb/gal. @ 60 degrees F.

pH*

28.0

38.8

31.0

30

0

10.6

5.5-7.2

32.0

44.3

35.4

20

32

11.06

5.5-7.2

UAN is approximately 75% ammonium or ammonium forming and 25% nitrate

* Varies with corrosion inhibitor used

Page 76: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Urea-Ammonium Nitrate Solution (UAN)

Made by mixing urea liquor and ammonium nitrate liquor and diluting

with a little water

Very difficult to make from solid urea and solid ammonium nitrate locally.

Page 77: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

UAN Solution• Advantages

– Flexibility– No high pressure equipment needed– Less power required for application– Compatible pesticides– Suited to application with irrigation water– Suited to topdressing crops

• Disadvantages– Higher purchase price– Volatilization potential

Page 78: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

How About UAN Leaf Burn ?

• Leaf burn on emerged crops– Burning is temporary– Least under cool temperatures and

low humidity– Dilute with water 50:50 ?– Winter wheat is very tolerant– Corn and grain sorghum are

tolerant but most herbicide combinations are not labeled post

Page 79: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Effect Of Urea Placed With Corn Seed(Minnesota)

N Applied with Seed

Emerged Population Grain Yield

lbs/acre plants/acre bu./acre

0 29,968 1817.5 21,127 156

15.0 15,246 14530.0 7,550 96

Page 80: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Selection of N Source/Method of Application

• Method of Application• Time of Application• Tillage System• Equipment Availability• Labor Availability• Personal Preference/Comfort• Flexibility Required••• Cost

Page 81: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

N Management Options“Best” Agronomic N Management Options

Subsurface ApplicationsIn-Season ApplicationSpring ApplicationN-Serve

“Best” Practical N Management Options

Avoiding High N Loss Risk SituationsIncorporation of Urea and UANNo Fall Applications On SandsDelay Fall Applications Until Soils Cooled ??Managing Surface Application With ResiduesUnderstand The N Cycle and Manage AccordinglyOthers ??

Page 82: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Total N Fall E. Spr Later 2003 2004 Average0 --- --- --- 49 42 46

40 0 40 0 69 75 7240 40 0 0 68 71 7040 20 20 0 69 73 71

80 0 80 0 95 88 9280 80 0 0 92 88 9080 40 40 0 94 89 92

120 0 120 0 96 89 93120 120 0 0 91 88 90120 60 60 0 95 87 91

80 0 40 40/F6 68 73 7180 0 40 40/F8 70 70 70

80 0 0 80/F6 67 70 6980 0 0 80/F8 51 58 55

N Rate and Application Timing Effect On Wheat YieldB. Gordon, KSU, Belleville

Page 83: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

NITROGEN

Page 84: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities
Page 85: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

N Source and Method For Conventional Till Grain SorghumLamo nd, 2004, KSU

50

70

90

110

130

0 30 60 90 120N Rate (lb N/a)

Yiel

d (b

u/a)

No-TillConventional

Page 86: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

Review Exercises. Nitrogen is an essential part of ___________________.

. Protein

. Plant enzymes.

. Chlorophyll.

. All of the above.

. None of the above.

. Which of the following is generally not a nitrogen deficiency symptom in plants?

. Slow growth rate.

. Pale green or yellow color.

Page 87: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

. Nitrogen may be lost from the nitrogen cycle through _________________.

. Nitrogen fixation by lightning.

. Animal manure.

. Nitrate leaching.

. Legume fixation.

. All the above.

. None of the above.

. About 10% of total soil nitrogen is found in the soil organic matter.

a. True b. False

Th b hi h l t il bl i it f t d b

Page 88: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

. A soil pH range of _____________ is optimum for nitrification.

. 4.5 to 5.5. b. 5.5 to 6.0. c. 6.0 to 8.5. d. 8.6 to 10.0.

. The installation of tile drainage in a field that frequently becomes waterlogged would most likely ____________________ denitrification.

a. Increase b. Decrease c. have no effect on

0. ____ions have the highest potential for leaching significant quantities of N from the soil.

a. Ammonium b. Nitrate c. Nitrite d. Ammonia

1. Most nitrogen fertilizer comes from the synthetic fixation of atmospheric nitrogen using UAN as a base product.

Page 89: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

3. Proper application depth is the single most important way to avoid seedling toxicity from anhydrous ammonia.

a. True. b. False.

4. In comparing ammonium nitrate fertilizer to urea, ammonium nitrate is__________ than urea.

. Higher in nitrogen content.

. Less subject to volatilization losses.

. Less expensive to produce.

. Less corrosive.

5. Volatilization loss from surface-applied urea is of most concern under which TWO of the following conditions?

Page 90: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

17. Which nitrogen fertilizer, when applied at equal rates of N, will create the greatest soil acidity?

a. Ammonium nitrate.b. Ammonium sulfate.c. Urea.d. UAN solutions.

8. All nitrogen fertilizer sources can be good choices from an economic standpoint if properly applied.

a. True. b. False.

19. Symbiotic nitrogen fixation refers to:

. Tie up of nitrogen by soil bacteria

. Production of available nitrogen in the soil by soil bacteria

. Production of available nitrogen by bacteria in legume nodules

Page 91: NITROGEN - Agronomy | Kansas State University · Nitrogen • Air – 78% Nitrogen – 35,000 Tons/Acre – Unavailable Form • Nitrogen Fertilization – Required in largest quantities

21. The major source of nitrate nitrogen that enters rivers and lakes is generally:

a. Legume fixation b. Denitrification.c. Nitrate leaching into drainage tile and surface water runoff from land.d. N in rainfall

22. Which mechanism of nitrogen loss is most likely to occur in the month following application under the following conditions? Urea-ammonium nitrate solution (UAN) is applied to grass pasture in late winter. The soil is a silt loam with a slope of 3-5%. There is no frost in the ground. Air temperatures are in the 30-45 degree range. There is 6 inches of precipitation in the form of rain or snow in the next 30 days.

a. Leaching of nitrate b. Denitrification of nitratec. Volatilization of ammonia d. Surface runoff of urea and nitrate

3. A nitrification inhibitor blocks conversion of:

a. NH4+ to NO2

-. (ammonium to nitrite) b. NO2-. to NO3

-.(nitrite to nitrate)c. Organic N to NH4

+ (organic N to ammonium) d. NO3-. to N2. (nitrate to elemental N)

4. The greatest potential for increasing nitrate pollution of ground water occurs with which of the following applications of nitrogen for row crops such as corn or sorghum:

a. Fall application of anhydrous ammoniab F ll li ti f UAN