Topping

Question 1 Why do plants have leaves? As a store for seed production

Historical Perspective Late topping/ full bloom Late topping/ full bloom Past Demand Past Demand Lighter bodied style of tobacco Lighter bodied style of tobacco Milder taste Milder taste Non-filtered Non-filtered Sucker control Sucker control Hand removal Hand removal No chemical control No chemical control

Physiological Aspect of Topping Leaf Spread Removal of non-beneficial nutrient sink Root stimulation

Timing Best when 10-25% of plants have one flower open Effects on plant Darker cured leaf color Prior to physiological maturity Prior to stalk hardening Increases root development More leaf expansion in lower part of plant

Yield Trends Bud Topping Yield loss in most varieties Good for late maturing varieties 10-25% Best for most varieties Good quality 50-75% Suckers initiated in some varieties 100%+ Yield decline Sucker initiation in all varieties Opportunistic diseases Senescence

Disease Incidence Hollow Stalk Late Top Harden Stalk Ragged Top

Effects of Topping Time on Yield 12 trials over 10 years

Topping Height Root system Supports a finite leaf yield Leaf number 20 leaves Larger leaves Highest Yield sometimes 26 leaves Smaller leaves Slightly higher Yield most times

Effects of Topping Time on Yield 17 trials over 9 years

Effects of Topping Time on Leaf Yield 17 trials over 9 years

Topping Study Labor Comparisons Lawrence Co. – Malcom Smith Farm

Topping Study Returns Comparisons Lawrence Co. – Malcom Smith Farm Based on $1.53 average price

On a Larger Scale 6 leaves per plant 42,000 per acre Based on 7000 population 420,000 Based on 10 acres 1,035,000 Based on 24 acres

Mechanical Topping

Sucker Control

Systemic Maleic Hydrazide Form Potassium Salt Brands Royal MH 30 Super Sucker Stuff Fair Plus Etc.

Systemic Maleic Hydrazide Activity Systemic Control of whole plant Control Cell Division Application 1.5 to 2 gal/a regular concentrate 1 to 1.5 gal/a high concentrate Avoid heat of the day Nozzles Fine – Hollow Cone Course – Solid Cone

Advantages Lasts for 3 to 4 weeks Ease of application Systemic Basipetal movement Reaches ground suckers

Major Disadvantage Residues in cured tobacco Standard Industry 80 ppm Maximum European 60 ppm Maximum Over application due to lack of confidence in the product

Disadvantages (Cont’d) Breakdown of control Poor application methods Too little volume Coverage Poor weather conditions Leaf not receptive under dry conditions

Disadvantage s (Cont’d) Artificial maturity Bronzing Tip burn Stops cell division Retards leaf expansion on small leaves Not rain safe Reapply full rate if rain within 6 hrs Reapply ½ rate if rain occurs within 6 to 12 hrs

MH Injury Residual MH left in sprayers from previous years can injure young plants

Contacts Fatty alcohols Brands Royal-Tac Fair 85 Sucker Plucker Off-Shoot T Activity Contact Control Kills actively growing tissue

Application Coarse spray (Full cone 3 nozzles arrangement) Rate (4-6% solution) Avoid temperatures in excess of 90 o F

Advantages No residue No bronzing Does not stop cell division Rain safe after 2 hrs

Disadvantages Short residual control Reapplication required If chemical misses sucker, no control (not systemic) Leaf Drop under high temperatures

Local Systemic Dinitroanaline (DNA) Prime+, Butralin & FluPro Activity Stops cell division Application Coarse spray (Full cone 3 nozzles arrangement) Drop lines Rate (2% solution in 50 gal/a) Run Down Jug method

Equipment Hand Jug method Backpack High Clearance Sprayer Drop Lines

Advantages Low residue Extended Control 5-7 weeks Stops cell expansion only in small suckers Slightly darker top grade when cured

Disadvantages Residual activity of chemical on cover crops Difficult to apply correctly with high clearance sprayer Escapes Liberation of dormant ground suckers

Combination MH & Prime+ or Butralin Activity Dual approach Systemic and Local systemic Controls Cell division

Why Coarse Nozzles? Provide large droplet size Like rain Runs down stalk Contacts all leaf axils Where suckers are Suckers more receptive than Leaf During dry weather Leaf cuticle more waxy

Nozzles Fine Nozzles Coverage on upper third of plant Covers mostly leaf During drought Dries on contact Does not come in contact with sucker bud

Application Coarse nozzles TG-5 / CE-5 or equivalent at mph TG-3 / CE-3 or equivalent at mph

Effects of Application of MH by Coarse vs Fine Nozzles on Yield of Burley Tobacco

Rate 1.5 gal/a MH (regular concentrate)+.5 gal/a of Prime+ or Butralin 1 gal high concentrate +.5 gal/a of Prime+ or Butralin

Influence of Sucker Control Across Four Location on Burley Tobacco Yield Locations = Bath, Knox, Jackson & Pendleton LSD 0.05 = 177

Average MH Residues by State Limited sample numbers on all but KY and TN 2000 & 2004 values are from warehouse sales only

of MH Residue Across All States 2000 & 2004 Distribution of MH Residue Across All States 2000 & 2004

MH Frequency Data for Kentucky 2000 & 2004 MH Residue Frequency Data for Kentucky 2000 & 2004

Range of MH Residues in Kentucky for Low 200 ppm

of Combination Advantages of Combination Higher yields Better returns Improved sucker control Lower MH residue Extended Control 5-7 wks Rain safety after 2 hrs Produces darker cured leaf Not as weather dependent No cover crop concern No ground sucker concern Improved grower confidence

Disadvantage Higher Cost

Controlling Late Season Insects

Aphid Options InsecticideRate/Acre Harvest Interval Small Plants Large Plants (days) Acephate, Bracket, Orthene 2/3 lb1 lb3 Orthene 97 3/4 lb 3 Fulfill 50 WDG 2.75 oz 14 Golden Leaf Tobacco Spray 2/3 qt1 - 1/3 qt5* Phaser 3E 2/3 qt1 - 1/3 qt5* Pravado 1.6 F 2 to 4 fl oz 14 Thiodan (Endosulfan) 2/3 qt1 - 1/3 qt5* Lannate 90 SP 1/2 lb 14 *Application of products containing endosulfan within 28 days of harvest can lead to increased residue on the crop. Do not spray in the heat of the day

Hornworm Options InsecticideRate/Acre Harvest Interval (days) Acephate (Orthene 75, Bracket) 1 lb3 Orthene 97 1/2 lb3 BT products (Agree, Biobit, Dipel, Javelin, Lepinox, Xentari) 0 Denim 0.16 EC 8 to 12 fl. oz.14 Endosulfan (Golden Leaf Tobacco Spray, Thiodan, Phaser) 2/3 to 1-1/3 qt5* Lannate SP 1/2 lb14 Sevin 80S 2-1/2 lbs0 Warrior 1.92 – 3.84 fl oz40 Tracer 4SC 1.4 to 2.9 fl oz*3 *Application of products containing endosulfan within 28 days of harvest can lead to increased residue on the crop. Do not spray in the heat of the day