Topping
Why do plants have leaves?

As a store for seed production
Question 1

Late topping/ full
bloom

Past Demand
Lighter bodied
style of tobacco
 Milder taste
 Non-filtered


Sucker control
Hand removal
 No chemical
control

Historical
Perspective
Physiological Aspect of
Topping



Leaf Spread
Removal of non-beneficial nutrient sink
Root stimulation

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
Timing
Yield Trends

Bud Topping



10-25%



Best for most varieties
Good quality
50-75%


Yield loss in most varieties
Good for late maturing varieties
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

Yield lb/a
Effects of Topping Time on Yield
3000
2795
2958
2876
2840
2500
625
631
594
604
1666
1755
1729
1657
504
553
570
579
Bud
10-25%
50-75%
100%
2000
1500
1000
500
0
Bloom Stage
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
3000
Yield lb/a
2500
2668
2755
2664
2722
2763
2697
686
701
710
703
686
676
1374
1442
1368
1421
1451
1390
608
612
586
598
625
630
20
26
2000
1500
1000
500
0
Leaf Number
-
Bud
10-25% 50-75% 100%
Bloom Stage
17 trials over 9 years
Effects of Topping Time on Leaf Yield
10
Yield g/leaf
8
6
4
8.28
7.32
6.58
7.45
7.57
7.38
2
0
20
26
Leaf Number
-
Bud
10-25% 50-75%
Bloom Stage
17 trials over 9 years
100%
Yield lb/a
Topping Study Labor Comparisons
Lawrence Co. – Malcom Smith Farm
2500
2447
2465
2000
784
778
1500
495
577
703
678
465
432
20
26
1000
500
0
Leaf Number
Topping Study Labor Comparisons
Lawrence Co. – Malcom Smith Farm
250
203.00
200
154.67
218.39
169.07
150
20
26
100
50
19.33 21.13
33.83 36.40
0
Cut hr/a
Strip hr/a
Cut Cost/a
Strip Cost/a
Topping Study Returns Comparisons
Lawrence Co. – Malcom Smith Farm
4000
$3,771.00
$3,744.00
20
26
3500
$/a
3000
Gross returns/a
Based on $1.53 average price
On a Larger Scale


6 leaves per plant
42,000 per acre


420,000


Based on 7000 population
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


European


80 ppm Maximum
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

Artificial maturity



Stops cell division


Bronzing
Tip burn
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
Disadvantage
s (Cont’d)
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 oF
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
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 44.5 mph
 TG-3 / CE-3 or
equivalent at 2.53 mph

Effects of Application of MH by Coarse
vs Fine Nozzles on Yield of Burley
Tobacco
4000
3500
Yield lb/a
3000
2500
2000
1500
1000
500
0
Bath
Fleming
Jackon
Knox
Laurel
Lawrenc
e
Nelson
Pendleto
Average*
n
Fine
2398
3105
1713
2352
2074
2697
2194
2911
2355
Coarse
2617
3474
1998
2498
2291
2949
2397
3014
2524
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
3000
2000
1500
1000
2557
2507
2380
2578
2411
2546
500
B
(.5
)
H
(1
)+
H
(1
.5
M
M
)+
B
(.5
)
.5
)
P(
H
(1
)+
H
(1
.5
M
M
)+
P(
.5
)
H
(2
)
M
H
(2
)F
0
M
Yield lb/a
2500
Locations = Bath, Knox, Jackson & Pendleton LSD 0.05 = 177
Average MH Residues by State
1997-2004
ppm MH
120
100
80
60
40
20
0
KY
IN
MO
NC
OH
TN
VA
Other
Limited sample numbers on all but KY and TN
2000 & 2004 values are from warehouse sales only
ALL
Distribution of MH Residue
Across All States 2000 & 2004
Frequency
120
90
60
30
0
0
1-40 41-80
81120
121160
161200
2000 (169)
28
62
50
20
7
2
2001 (275)
87
105
62
10
5
5
2002 (252)
92
79
50
21
5
1
2003(241)
76
95
53
12
3
2
2004(184)
61
75
27
9
7
1
ppm MH
2001 (275)
2002 (252)
2000 (169)
201240
241280
281320
1
1
2
2
2
2003(241)
1
2004(184)
MH Residue Frequency Data for
Kentucky 2000 & 2004
Frequency
80
70
60
50
40
30
20
10
0
0
Jan41-80
40
81120
121160
161200
2000 (116)
16
41
38
15
5
1
2001 (169)
37
70
45
8
5
3
2002(149)
49
47
33
13
3
1
2003(145)
32
62
38
10
2
1
2004(109)
28
49
17
7
2000 (116)
2001 (169)
5
0
ppm MH
2002(149)
201240
241280
>280
1
0
2
2
1
2003(145)
1
2004(109)
Range of MH Residues in
Kentucky for 1997 - 2004
100
90
80
70
60
% 50
40
30
20
10
0
Extremely High
Very High
High
Medium
Low
1997
1998
1999
2000
2001
2002
2003
2004
2.11
14.21
20.53
29.47
33.68
8.73
9.82
13.82
29.82
37.82
5.45
14.55
21.09
25.45
33.45
0
5.17
12.93
32.76
49.14
0.59
4.73
4.73
26.63
63.31
2.01
2.68
8.72
22.15
64.43
0
2.07
6.9
26.21
63.45
2.75
4.59
6.42
15.6
70.64
Low < 41, Medium = 41-80, High = 81-120, Very High = 120 - 200, Extremely High >200 ppm
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
Insecticide
Rate/Acre
Small Plants
Harvest Interval
Large Plants
(days)
Acephate, Bracket, Orthene
2/3 lb
1 lb
3
Orthene 97
3/4 lb
3/4 lb
3
2.75 oz
2.75 oz
14
Golden Leaf Tobacco Spray
2/3 qt
1 - 1/3 qt
5*
Phaser 3E
2/3 qt
1 - 1/3 qt
5*
2 to 4 fl oz
2 to 4 fl oz
14
Thiodan (Endosulfan)
2/3 qt
1 - 1/3 qt
5*
Lannate 90 SP
1/2 lb
1/2 lb
14
Fulfill 50 WDG
Pravado 1.6 F
*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
Insecticide
Rate/Acre
Harvest
Interval
(days)
Acephate (Orthene 75, Bracket)
1 lb
3
Orthene 97
1/2 lb
3
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 qt
5*
Lannate SP
1/2 lb
14
Sevin 80S
2-1/2 lbs
0
Warrior
1.92 – 3.84 fl oz
40
1.4 to 2.9 fl oz*
3
Tracer 4SC
*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