1. Nitrogen Sources for Cotton Across the Belt
Glen Harris – UGA (Tifton)

2. Ammonium Nitrate vs. Urea For Cotton Production in Georgia
Glen Harris
University of Georgia (Tifton)

3. Nitrogen Sources for 2007
Glen Harris
UGA - Tifton

4. N2 + 3H2 >>>>>>> 2NH3
Industrial N Fixation
Haber Bosch Process
N2 + 3H2 >>>>>>> 2NH3
Heat + Pressure
Natural Gas = Ingredient + Fuel Source

5. CaNO3 ?
KNO3 ?
Source: PPI Soil Fertility Manual

6. Choosing an N Source for Cotton
“All sources of nitrogen are considered equal in their ability to provide nitrogen to cotton. No one form of nitrogen is superior to another if all are applied correctly. Base choices on price, availability and ease of application”
Mississippi State University Extension Service

7. Comparing Nitrogen Fertilizers
Nitrogen Source
Comments
Anhydrous Ammonia
Gas
Inexpensive
Safety/Dealer Insurance
Methamphetamines
UAN Solutions
Liquid
Urea+Ammonium+Nitrate
Urea
Solid
Concentrated
Volatilization
Ammonium Nitrate
Regulations
Availability
Higher Cost

9. Nitrogen Fertilizers Sold in Georgia – FY 06
(Tons x 1000)

10. Ammonium Nitrate Sold in Georgia
(Tons x 1000)

11. Urea Sold in Georgia
(Tons x 1000)

12. The Comparison Ammonium Nitrate Urea Solid 34 % N 46 % N
Salt Index=105
Salt Index=75
Safety/Regulations
Availability
Volatilization
$315/ton
$0.46/lb N
$345/ton
$0.38/lb N

14. Has Urea Gotten a Bum Rap ?
Worst Case Scenerio Loss = 30 %
Not as Good as Ammonium Nitrate ?
Not as “Quick” as Ammonium Nitrate ?

15. Yields (lb lint/a) Late Sidedress N Source – Expo 2005 a ab ab bc c c

17. Conditions that lead to NH3 loss
Enough soil water for hydrolysis, but
not enough to leach urea into soil
Low pH buffering capacity (low OM)
High temperatures
High wind speed NH
3 gas -
clay - NH
3 gas OM - NH NH NH
+ H 4 + 4 + aq
3 aq +
CO(NH )
+ 2H
O + H
2NH
+ HCO 2 2 2 + 4 + 3 -
urea
urease

18. How To Limit Volatilization Losses from Urea
Incorporate Into Soil with Tillage
Inject Beneath Soil Surface
Apply in a Band
Apply When Soil Temp Below 50 F
Irrigate Shortly After Application
Pray for Rain on Dryland
Use a Urease Inhibitors
Ex. Agrotain

19. Fertilizer additive that inhibits
degradation of urea by urease
Urease = enzyme produced by
soil microbes
Does not affect microbes
(or other soil organisms) directly
Reduces loss of surface applied
urea-N to volatilization
14-Day Inhibition period – rapid drying conditions
N-(n-Butyl) –thiophosphoric triamide aka NBPT

21. Net Return ($/a) by “Rain-Free Days”
# of Rain-Free Days

22. Evaluation of a Urease Inhibitor
with Sidedress Nitrogen in the Southeast
Glen Harris
University of Georgia - Tifton

23. AGROTAIN vs N-Serve
Urease Inhibitor Nitrification Inhibitor

24. ESN = Environmentally Smart Nitrogen
Polymer Coated Urea
Company = Agrium
“Controlled Release”
“Releases as the Soil Warms”
Corn in Ohio and Canada (+ Kentucky)
Cotton in Georgia

25. Split Applications vs. Slow Release

26. Yields (lb lint/a) 2006 ESN vs. Nitrate Sunbelt Expo (Moultrie, GA)
30SR
60AN
30AN
60SR
30SR
30AN
60AN
30SR
60SR

27. Yields (lb lint/a) 2006 ESN vs. Urea Sunbelt Expo (Moultrie, GA) 30SR

28. “Enhanced Efficiency (EE)” Fertilizers
New Term Coined by The Fertilizer Institute (TFI)
“…products that minimize the potential of nutrient loss to the environment.”
Slow/Controlled Release
Absorbed
Coated
Occluded
Reacted
Stabilized/Additive
Nitrification Inhibitors
Urease Inhibitors
Stabilizers
Association of American Plant Food Control Officials (AAPFCO)

29. Yields (lb lint/a) 2006 Tetra UAN/CaCl Sunbelt Expo 0 UAN 0 CaCl 0 UAN

30. Yields (lb lint/a) 2006 Englehard/Attapulgite Clay Sunbelt Expo 30 UAN

31. The “Original” Slow Release Fertilizer
Poultry Litter
The “Original” Slow Release Fertilizer
(+ Biosolids and Legume Cover Crops ?)

32. Time for Questions ?