Tobacco Production Update

1
Tobacco Production Update

• Bob Pearce, Gary Palmer, Andy Bailey
• Extension Tobacco Specialists
• Kenny Seebold
• Extension Plant Pathologist

2
Topics

• Nitrogen sources for tobacco
• Revised nitrogen rates for tobacco
• Sucker control options
• No MH options
• Variety update
• Disease update

3
Nitrogen Fertilizer Issues

• Economics
• Leaf prices down
• N fertilizer prices up
• Price tied to natural gas
• Transportation costs up
• Nitrosamine concerns
• Tobacco companies want less N applied
• Quality concerns
• Too little thin body, poor yield
• Too much delayed maturity, fat stems

4
Ammonium Nitrate Issues

• Most common N source for tobacco growers
• Homeland security concerns
• Can be used to make explosives
• Easy availability
• Some manufacturing plants have closed
• Tighter supplies
• Higher costs
• Sales regulations
• Permits needed to purchase large quantity?
• Some dealers reluctant to stock?

5
Price Per Unit of Nitrogen for Selected
Fertilizer Materials
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Alternative N Sources

• Anhydrous ammonia (82 N)
• Lowest cost per unit of N
• Limited availability
• Special equipment needed
• Stored as liquid under pressure
• Special injectors needed
• Used in illegal meth production
• Feasible only if equipment already available
• Placement concerns
• Delayed uptake
• Phyto-toxicity if close to plants

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Alternative N Sources

• Anhydrous ammonia (82 N)
• Reaction in soil
• NH3 2O2 ? H NO3- H2O
• Same lime requirement as AN
• Suggestions for use
• Inject 6 to 8 inches deep
• 7 to 10 days before setting

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Alternative N Sources

• Ammonium sulfate (21 N)
• Specialty fertilizer
• Use on acid loving crops
• Use on high pH soils
• Relatively high cost per unit N
• Limited availability
• Soil reaction
• (NH4)2SO4 4O2 ? 4H 2NO3- SO42- 2H2O
• 3X lime requirement of AN
• Not feasible for large scale use on tobacco

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Alternative N Sources

• Urea (46 N)
• Intermediate cost
• Handling similar to ammonium nitrate
• Can impregnate some chemicals
• Same lime requirement as AN
• Converted to nitrate in the soil
• Subject to loss if surface applied
• Apply to dry soil
• Incorporate or water in
• Delayed uptake (Dont use for sidedress)
• Feasible alternative if managed properly

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Alternative N Sources

• Non Pressure Solutions (28 32 N)
• Intermediate cost
• Mixture of urea, ammonium nitrate, and water
• Relatively easy to transport, store, and apply
• Most nurse tanks
• Many types of sprayers
• Corrosive to equipment
• Should be incorporated
• Can be used a a carrier for spray applications
• Limited availability
• Feasible for tobacco production

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Alternative N Sources

• Calcium Ammonium Nitrate (27 N)
• Ammonium nitrate mixed with lime
• 78 ammonium nitrate
• Theoretically similar to ammonium nitrate
• Can impregnate some chemicals ?
• Relatively high cost?
• Availability?
• Limited practical experience

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Alternative N Sources

• Sodium Nitrate (16 N)
• Calcium Nitrate (15.5 N)
• Sodium-Potassium Nitrate (15 N)
• Immediate uptake (good for sidedress)
• Good for low pH soils
• Erratic availability
• High cost
• Low analysis high transport cost

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Conversion to Nitrate in soil
of Fertilizer as NO3-N of Fertilizer as NO3-N of Fertilizer as NO3-N
N Source N Source Weeks After Application Weeks After Application Weeks After Application
0 3 6
Ammonium Nitrate Ammonium Nitrate 50 80 90
Anhydrous Ammonia Anhydrous Ammonia 0 20 65
Urea Urea 0 50 75
UAN Solution UAN Solution 25 60 80
Nitrate Sources Nitrate Sources 100 100 100
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Effects of Ammonium Nitrate Application on Soil
pH
Anhydrous Ammonia, Urea, UAN solutions similar
15
Effect of Liming an Acid Soil Prior to Use of
Urea and Sodium Nitrate Sources of Nitrogen
Both N sources applied at 225 lb N/A pre-plant.
Soil pH (water) measured at midseason of each
year. Soil pH before liming was 5.4.
16
Effect of Liming an Acid Soil Prior to Use of
Urea and Sodium Nitrate Sources of Nitrogen
Both N sources applied at 225 lb N/A pre-plant.
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Nitrogen Source StudyHarrison Co. Keith Smith
Farm
100 units AN Broadcast Sidedressed with 170
units each, AN Ammonium Nitrate, U Urea, CN
Calcium Nitrate, SN Sodium Nitrate

18
Conventional Fertility TrialMonroe Co. Al
Pedigo Farm
Broadcast Sidedress
Number lbs of product, AN Ammonium Nitrate,
CN Calcium Nitrate, SN Sodium Nitrate, U
Urea
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No-till Fertility TrialMonroe Co. Al Pedigo
Farm
Broadcast Sidedress
Number lbs of product, AN Ammonium Nitrate,
CN Calcium Nitrate, SN Sodium Nitrate, U
Urea
20
Effects of Sidedressing Different Sources of
Nitrogen on Burley YieldElliot Co. Tracy D.
Kitchen Farm
450 Ammonium Nitrate Broadcast followed by 100
lb/a of Nitrogen Sidedressed. Am Ammonium, Ca
Calcium Na Sodium. There were no significant
differences.
21
Effect of Nitrogen Source on Burley
YieldMarshall Co. Glen Thompson Farm
2579 2605 2650
2684 225
150 units Urea Broadcast Sidedressed with 100
units each at sidedressing, Ca Calcium and Na
Sodium
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Revised Nitrogen Rates

• AGR-1 will have a new table for N on tobacco
• Based on crop history (same as old)
• No additional N for continuous tobacco
• Soil drainage formally considered
• Typical recommendation 50 lbs. N/A less
• Rate lower if sidedressing is practiced
• Economically sound recommendations
• Reduce incidence of over-application

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Revised Nitrogen Recommendations for Burley and Dark Tobacco. Revised Nitrogen Recommendations for Burley and Dark Tobacco. Revised Nitrogen Recommendations for Burley and Dark Tobacco.
Well Drained Soil Moderately Well Drained Soil
------------Lb N/A------------ ------------Lb N/A------------
Low N levels following tobacco or row crops 225-250 250-275
Medium N levels first-year tobacco following a grass or grass-legume sod 200-225 225-250
High N levels first-year tobacco following legume sod or legume cover crop 150-175 175-200
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Effects of Nitrogen Rates on Burley Tobacco at
Spindletop Farm (Maury Silt Loam)

• MacKown, Sutton and Crafts-Brander 1994

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Nrate across location years and method
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Effect of N rate and method of application on
burley tobacco yield.
If 1/3 or more is sidedressed reduce total amount
of N by 15 to 25 lbs./A
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Summary

• Encourage growers to compare costs and consider
  alternative N sources
• Revised N rates
• Rates lowered by about 50 lbs./A
• Will not significantly lower yield
• Improved quality
• Promotes desired chemical properties
• Reduce rate if sidedressing is practiced