Result Demonstration/Applied Research Report
2007 Tom Green County
Cotton Harvest Aid Demonstration
Cooperators: John and Doug Wilde
Rick Minzenmayer - IPM for Runnels and Tom Green Counties
Steve Sturtz, Tom Green County Extension Agent - Agriculture
Dr. Billy Warrick, Extension Agronomist (San Angelo, Texas)
Summary
Eighteen treatments were applied over the top of cotton on October 1 to prepare for harvest. The plot was established on John and Doug Wilde’s farm located on the Southeast side of San Angelo, TX. The chemicals were applied to FiberMax 1880 B2F cotton that had 75 percent of its bolls open. Leaf shed was less than one percent when the plot was established. These plots were evaluated on October 8 (seven days after treatments were applied) and October 15, 2007 (14 days after the treatments were applied and seven days after follow-up treatments were applied). Most of the treatments resulted in an increase in open bolls, leaf defoliation, and leaf desiccation. In this test favorable environmental conditions resulted in faster performance of the harvest aids applied. These included warm day and night temperatures, minimal rainfall with no impact on soil temperature and bright sunny days for most of the test period.
Objective
In the Southern Rolling Plains, cotton is usually planted starting in mid-May. Because of this planting date, many producers do not use harvest aids to terminate the cotton. When growing conditions are favorable, most of the cotton in this area is ready for harvest thirty days before the first killing freeze. The delay in harvest reduces the income of farmers due to the loss of lint yield and fiber quality. Even though the cost of several of the harvest aid treatments is expensive, there is usually a product that is economically justified that can be used effectively for crop termination. The intent of this field test is to: 1) determine the effectiveness of harvest aids at defoliating, desiccating, and opening bolls on cotton; 2) provide producers the opportunity of observing how effectively the harvest aid materials work; and 3) determine the economic feasibility of using the harvest aid material.
Materials and Methods
Cooperating County Producers: John and Doug Wilde
Location: Southeast edge of San Angelo, TX
Crop Production Information:
Variety Planted: FiberMax 1880 B2F
Planting Date: May 14, 2007
Planting Rate: 45,000 seeds/acre
Planting Pattern: Solid on 40 inch rows
Irrigation: Furrow irrigation
Number of Irrigations: One application during the season of 4 to 6 inches of water
Harvest Aid Application Information for October 1, 2007:
Wind Speed: 3.0 to 6.0 miles per hour
Wind Direction: Southeast
Air Temperature: 85 to 880 Fahrenheit
Relative Humidity: 48 to 59%
Carrier: 16.0 gallons of water per acre
Pressure: 35 pounds per square inch
Nozzle Size: 11002 extended range flat fan over the top of each row and one 8002 Extended Range nozzle on each side of the row
Boom Height: 42 inches
Cotton Height: 28 to 34 inches
Ground Speed: 4.0 miles per hour
Application Device: Self propelled rig with 13.33 foot boom
Plot Size: 13.33 feet X 50 feet
Test Design: Randomized block design replicated four times
Harvest Aid Application Information for October 8, 2007:
Wind Speed: 2.0 to 3.0 miles per hour
Wind Direction: North
Air Temperature: 75 to 820 Fahrenheit
Relative Humidity: 50 to 62%
Carrier: 16.0 gallons of water per acre
Pressure: 35 pounds per square inch
Nozzle Size: 11002 extended range flat fan over the top of each row and one 8002 Extended Range nozzle on each side of the row
Boom Height: 42 inches
Cotton Height: 28 to 34 inches
Ground Speed: 4.0 miles per hour
Test Design: Randomized block design replicated four times
Plant Information
At the time of application, the upper most cotton bolls were cross-sectioned, the seed coats were dark, and the cotyledons well developed. Cotton height averaged 30 inches and the percent open bolls averaged 75 percent. Overall the plants were healthy and unstressed and leaf defoliation was less than one percent.
Weather Information
Rainfall Information (Date and Amount)
October 3 0.20 inch
-----------
Total October Rainfall 0.20 inch
Maximum and Minimum Air Temperatures for October 1 - October 14, 2007
Date |
Max Air |
Min Air |
Date |
Max Air |
Min Air |
1 |
89 |
65 |
8 |
89 |
59 |
2 |
89 |
70 |
9 |
83 |
62 |
3 |
93 |
66 |
10 |
85 |
56 |
4 |
91 |
67 |
11 |
86 |
59 |
5 |
91 |
59 |
12 |
88 |
59 |
6 |
90 |
61 |
13 |
89 |
65 |
7 |
88 |
61 |
14 |
86 |
63 |
Results and Discussion
The cotton at the time of application was 75 percent open and most of the remaining bolls were mature. The application of the harvest aids did impact boll opening, percent leaf defoliation and percent leaf desiccation. Several factors contributed to the success of the harvest aids applied. These include: 1) the cotton was mature; 2) chemical coverage was excellent due to gallonage, pressure used, and wind. Leaf shed was less than one percent when the plot was established. These plots were evaluated on October 8 (seven days after treatments were applied) and October 15, 2007 (14 days after the treatments were applied and seven days after follow-up treatments were applied). In this test several factors resulted in fast performance of the harvest aids applied. These include favorable daytime and nighttime temperatures, sunny and cloud free days. The data collected on October 8 is reported in Table 1 and the data collected October 15 is reported in Table 2.
The first seven days (October 1 to October 8, 2007)
Maximum air temperatures ranged from 88 to 93 degrees Fahrenheit for the seven days after harvest aids were applied. The nighttime air temperatures ranged from 59 to 67 degrees Fahrenheit. With these temperatures the harvest aids worked better than expected. The increase in boll opening ranged from two to seven percent more than the check and this was statistically significant in six of the treatments. Leaf desiccation ranged from two to 37 percent higher than the check plot which was statistically different in six of the treatments. Leaf defoliation was higher than the check in all treatments on October 8, 2007 (seven days after the treatments were applied). The data collected on October 8 is reported in Table 1.
The formation of the abscission layer between the petiole and the main stem formed quickly and the follow-up applications were applied seven days later. The harvest aids applied on October 8 are listed at the bottom of Table 2.
Seven days after the second application of harvest aids (October 8 to October 15, 2007)
Maximum air temperatures ranged from 83 to 89 degrees Fahrenheit for the seven days following the second application of harvest aids. The nighttime air temperatures ranged from 56 to 65 degrees Fahrenheit. With these temperatures all of the harvest aids worked well. The increase in boll opening increased from zero to five percent from the rating made October 8. There was a significant difference in all treatments when compared to the check. Leaf desiccation ranged from three to 50 percent higher than the check plot which was statistically different in all treatments. Leaf defoliation was higher than the check in all treatments on October 15, 2007 (14 days after the test was started and seven days after the second application of harvest aids were applied). The data collected on October 15 is reported in Table 2.
The combination of numbers shown in the defoliation and desiccation columns in the Table allows you the opportunity of determining the green leaves remaining by subtracting that total from 100. No remaining green leaves are preferred on cotton to be harvested. The green leaves when harvested and placed into a module or trailer, are a source of unwanted moisture which can result in a high temperature inside the module or trailer. None of the treatments had a combined number of 100; the closest was Finish 6 Pro at 21 ounces plus Ginstar at 6 ounces followed by Gramoxone Inteon at 24 ounces plus Induce at 10.25 ounces. With a lint yield in the 500 to 600 pound range you would prefer to keep leaf desiccation at 20 percent or less, which should result in a leaf grade of 1 to 3.
In this test, regrowth was evident but not developed enough to interfere with harvest 14 days after the plot was established. Some of the materials applied are known to be better at desiccating or removing juvenile growth. These include Aim, Blizzard, ET, and Ginstar. Please note that a crop oil concentrate was used in tank mixes that contained Aim, Blizzard, and ET. For maximum performance with these products, crop oil concentrate (C.O.C.) is an important part of the tank mix.
Economic Analysis
This test can be used to document the results obtained from the use of harvest aids. If the same treatments are consistently at the top of the list for several years, then producers may want to incorporate those treatments into their cotton production program. It is important to remember that a higher lint yield is not the only way of increasing profit from the use of a harvest aid. Other factors include: timely harvest, improved fiber quality, improved harvesting efficiency, and higher percent lint turnout at the gin.
Table 1. Tom Green County Cotton Harvest Aid Test (Wilde Farm, 2007)
October 8, 2007 (7 days after treatments were applied)
(NOTE: Linked to each harvest aid treatment is a picture of the plot)
Harvest Aid Chemicals Applied (4 rows of each) |
Rate Applied Per Acre |
Cost of Harvest Aid Per Acre |
% Open Bolls |
% Defoliation |
% Desiccation |
0.5 oz. + 24 oz. + 20.5 oz. |
$3.61 + $4.68 + $1.43 |
80.0 a |
60.00 abc |
3.75 bc |
|
0.5 oz. + 48 oz. + 20.5 oz. |
$3.61 + $9.36 + $1.43 |
81.25 a |
56.25 abcd |
8.00 bc |
|
1.50 oz. + 24 oz. + 20.5 oz. |
$3.40 + $4.68 + $1.43 |
80.0 a |
55.00 abcd |
2.50 bc |
|
1.50 oz. + 48 oz. + 20.5 oz. |
$3.75 + $9.36 + $1.43 |
78.75 ab |
57.50 abcd |
7.50 bc |
|
1.0 oz. + 24 oz. + 20.5 oz. |
$4.22 + $4.68 + $1.43 |
78.75 ab |
51.25 bcde |
7.50 bc |
|
1.0 oz. + 48 oz. + 20.5 oz. |
$4.22 + $9.36 + $1.43 |
80.0 a |
52.50 abcd |
8.75 bc |
|
- |
- |
75.0 b |
2.75 f |
0.00 c |
|
0.5 oz. + 24 oz. + 20.5 oz. |
$3.61 + $4.68 + $1.43 |
78.75 ab |
51.25 bcde |
3.25 bc |
|
0.5 oz. + 48 oz. + 20.5 oz. |
$3.61 + $9.36 + $1.43 |
81.25 a |
63.75 ab |
4.75 bc |
|
1.50 oz. + 32 oz. + 20.5 oz. |
$3.40 + $6.24 + $1.43 |
81.25 a |
58.75 abc |
4.50 bc |
|
1.50 oz. + 12 oz. + 10.25 oz. |
$3.75 + $2.53 + $1.68 |
78.75 ab |
58.50 abc |
14.25 b |
|
6.0 oz. |
$9.60 |
80.0 a |
65.00 ab |
7.50 bc |
|
24.0 oz. + |
$5.06 + |
77.5 ab |
36.25 e |
37.50 a |
|
32.0 oz. + |
$6.75 + |
81.25 a |
41.25 de |
37.50 a |
|
16.0 oz. + |
$3.38 + |
78.75 ab |
43.75 cde |
27.50 a |
|
16.0 oz. + 16.0 oz. |
$5.38 + $3.12 |
77.5 ab |
57.50 abcd |
6.75 bc |
|
32.0 oz. + 10.25 oz. |
$15.49 + $1.68 |
81.75 a |
65.00 ab |
8.25 bc |
|
21.0 oz. + 6.0 oz. |
$10.16 + $9.60 |
82.5 a |
68.75 a |
15.00 b |
|
24.0 oz. + 0.75 oz. |
$5.06 + $3.17 |
82.5 a |
53.75 abcd |
30.00 a |
Table 2. Tom Green County Cotton Harvest Aid Test (Wilde Farm, 2007)
October 15, 2007 (14 days after treatments were applied; 7 days after follow-up treatments were applied)
(NOTE: Linked to each harvest aid treatment is a picture of the plot)
Harvest Aid Chemicals Applied (4 rows of each) |
Rate Applied Per Acre |
Cost of Harvest Aid Per Acre |
% Open Bolls |
% Defoliation |
% Desiccation |
0.5 oz. + 24 oz. + 20.5 oz. |
$3.61 + $4.68 + $1.43 |
81.25 cd |
79.25 a |
4.75 de |
|
0.5 oz. + 48 oz. + 20.5 oz. |
$3.61 + $9.36 + $1.43 |
82.50 bcd |
79.50 a |
5.75 de |
|
1.50 oz. + 24 oz. + 20.5 oz. |
$3.40 + $4.68 + $1.43 |
82.50 bcd |
82.75 a |
3.00 de |
|
$3.75 + $9.36 + $1.43 |
83.75 abcd |
81.25 a |
4.50 de |
||
1.0 oz. + 24 oz. + 20.5 oz. |
$4.22 + $4.68 + $1.43 |
81.25 cd |
73.50 a |
6.50 de |
|
1.0 oz. + 48 oz. + 20.5 oz. |
$4.22 + $9.36 + $1.43 |
85.00 abc |
79.50 a |
5.00 de |
|
- |
- |
75.00 e |
10.00 e |
0.00 e |
|
0.5 oz. + 24 oz. + 20.5 oz. |
$3.61 + $4.68 + $1.43 |
83.00 bcd |
81.00 a |
3.50 de |
|
0.5 oz. + 48 oz. + 20.5 oz. |
$3.61 + $9.36 + $1.43 |
84.50 abcd |
81.50 a |
3.25 de |
|
1.50 oz. + 32 oz. + 20.5 oz. |
$3.40 + $6.24 + $1.43 |
83.25 abcd |
80.50 a |
4.50 de |
|
1.50 oz. + 12 oz. + 10.25 oz. |
$3.75 + $2.53 + $1.68 |
81.25 cd |
74.50 a |
12.50 cd |
|
Ginstar 4/ |
6.0 oz. |
$9.60 |
83.75 abcd |
82.50 a |
6.25 de |
24.0 oz. + |
$5.06 + |
81.25 cd |
45.00 cd |
42.50 a |
|
32.0 oz. + |
$6.75 + |
81.25 cd |
38.75 d |
50.00 a |
|
16.0 oz. + |
$3.38 + |
80.00 d |
53.75 bc |
25.00 b |
|
16.0 oz. + 16.0 oz. |
$5.38 + $3.12 |
80.00 d |
80.00 a |
6.25 de |
|
32.0 oz. + |
$15.49 + |
86.75 ab |
80.00 a |
8.75 cde |
|
21.0 oz. + 6.0 oz. |
$10.16 + $9.60 |
87.50 a |
77.50 a |
16.25 c |
|
24.0 oz. + 0.75 oz. + 20.5 oz. |
$5.06 + $3.17 + $1.43 |
82.50 bcd |
57.50 b |
26.25 b |
Follow up treatments applied on October 8
1/ Blizzard @ 0.5 oz. ($3.61) + Herbimax (C.O.C.) @ 1.0% v/v ($1.43) = $5.04
2/ ET @ 1.50 oz. ($3.40) + Herbimax (C.O.C.) @ 1.0% v/v ($1.43) = $4.83
3/ Aim @ 0.75 oz. ($3.16) + Herbimax (C.O.C.) @ 1.0% v/v ($1.43) = $4.59
4/ Gramoxone Inteon @ 24 oz. ($5.06) + Induce (N.I.S.) @ 0.5% v/v ($1.68) = $6.74
5/ Gramoxone Inteon @ 20 oz. ($4.22) + Induce (N.I.S.) @ 0.5% v/v ($1.68) = $5.90
6/ Firestorm @ 16 oz. ($4.38) + Induce (N.I.S.) @ 0.5% v/v ($1.68) = $6.06
7/ No follow up harvest aid was applied
NOTE: In Table 2 the individual or combination of letter a, b, c, d, or e shown beside the number are to indicate statistical significance. There is no statistical difference between numbers that have the same letter (even when there appears to be a large difference in results between the materials applied). Also, to account for 100 percent of the leaves you would add the percent defoliation plus the percent dessication and subtract from 100. The difference represents the number of original green leaves still remaining on the plant.
Acknowledgments
I want to take this opportunity to thank:
- John and Doug Wilde for their help in plot establishment and management.
- Bayer CropScience, Chemtura, DuPont, Nichino America, and Syngenta Crop Protection for supportingI would also like to thank the companies that provided the chemicals for this harvest aid test. These include:
- Bayer CropScience who provided the Def, Finish 6 Pro, Ginstar, and Prep
- Chemtura who provided the Blizzard and Firestorm
- DuPont who provided the FirstPick
- FMC Corporation who provided the Aim
- Helena Chemical Company who provided the Induce
- Nichino America who provided the ET
- Syngenta Crop Protection, Inc. who provided the Gramoxone Inteon
- Tri-State Chemical DBA United Agra Products (UAP) who provided the C.O.C. (Herbimax)
Trade names of commercial products used in this report are included only for better understanding and clarity. Reference to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by the Texas A&M University System is implied. Readers should realize that results from one experiment do not represent conclusive evidence that the same response would occur where conditions vary.