Investigation of the Efficiency of TE-3 Soil Fumigation on Pine Seedlings at the Weyerhaeuser Quail Ridge Nursery
1. Investigation of the Efficiency of TE-3 Soil Fumigation on Pine Seedlings at
the Weyerhaeuser Quail Ridge Nursery
Photo provided by Bruce Francis
By
Jordan Livingston
2. Table of Content
Introduction .......................................................................................................................................1
Methods.............................................................................................................................................1
Materials............................................................................................................................................2
Results...............................................................................................................................................3
Discussion..........................................................................................................................................4
Table 1: Tri-Brom 80 Germination Tracking ........................................................................................5
Table 2: TE-3 at 250lbs/ac Germination Tracking.................................................................................6
Table 3: TE-3 at 300lbs/ac Germination Tracking.................................................................................7
Table 4: TE-3 at 350lbs/ac Germination Tracking.................................................................................8
Figure 1: Family 181210.WL Germinaiton Rate ...................................................................................9
Figure 2: Family 111076.WL Germination Rate .................................................................................10
Table 5: Family 181210.WL Crop Tracking – Tri-Brom 80 Treatment Method.....................................11
Table 6: Family 181210.WL Crop Tracking – TE-3 at 250lbs/ac Treatment Method.............................12
Table 7: Family 181210.WL Crop Tracking – TE-3 at 300lbs/ac Treatment Method.............................13
Table 8: Family 181210.WL Crop Tracking – TE-3 at 350lbs/ac Treatment Method.............................14
Table 9: Family 111076.WL Crop Tracking – Tri-Brom-80 Treatment Method ....................................15
Table 10: Family 111076.WL Crop Tracking – TE-3 at 250lbs/ac Treatment Method ...........................16
Table 11: Family 111076.WL Crop Tracking – TE-3 at 300 lbs/ac Treatment Method ..........................17
Table 12: Family 111076.WL Crop Tracking – TE-3 at 350 lbs/ac Treatment Method ..........................18
Figure 3: Family 181210.WL Height Growth .....................................................................................19
Figure 4: Family 111076.WL Height Growth .....................................................................................20
Figure 5: Family 181210.WL Diameter Growth..................................................................................21
Figure 6: Family 111076.WL Diameter Growth..................................................................................22
References .......................................................................................................................................23
Attachment 1: Map of Nursery/Fumigation Treatment Block...............................................................24
Attachment 2: Map of Soil Fumigation Treatments in Block 1-5..........................................................25
Attachment 3: Bed Diagram..............................................................................................................26
3. 1
Introduction
Soil fumigation is a very important nursery operation because it ensures that the crop has a
vigorous start and can grow with little to no competition. This practice is aimed at lowering the
cost and need of post planting pest management (Carpenter 2). The Weyerhaeuser Quail Ridge
Nursery located in Aiken, South Carolina, uses soil fumigation to help increase the survival of
their pine seedlings and reduce the competition from undesirable species. The current soil
fumigant used operationally at the nursery is Tri-Brom 80. This fumigant is 80% Methyl
Bromide and 20% Chloropicrin (TriEst Ag Group, October 2012). A new product that has
recently come out on the market is the TE-3 fumigant. This is composed of three different
chemicals. It consists of 33% Chloropicrin, 23% 1, 3-Dichlorpropene, and 44% Dimethyl
disulfide (TriEst Ag Group, May 2012). The goal of this new fumigant is to reduce the buffer
zone distance required when applying the soil fumigant and to keep the buffer zone on company
property. Accounting for the credits the nursery receives because of the tarp reduction, the buffer
zone for a 13.8 acre block for Tri-Brom 80 at 275lbs/ac is 213ft. The buffer zones for TE-3 at
250lbs/ac, 300lbs/ac, and 350lbs/ac are all 225ft. Buffer zones that extend past the nursery
boundaries require written consent from the landowner. If the buffer zone includes a residential
area such as a house, the owner has to provide written consent that they will vacate the buffer
zone during the entire buffer zone period. Also for methyl bromide formulations with less than
20% chloropicrin, air monitoring instruments have to show concentrations are below action
levels before residents can reenter the property (Reliable Process for Planning and Management
of Soil Fumigation 5). The future for Tri-Brom 80 is uncertain so a new alternative needs to be
found. The TE-3 fumigant needs to guarantee that it can be just as effective in controlling weeds
and other pest related problems that the seedlings could encounter while growing in the nursery.
Methods
The Weyerhaeuser Quail Ridge Nursery brought in a contractor, TriEst Ag Group, to apply the
soil fumigation chemicals to the block where the study was going to be conducted. Tri-Brom 80,
the current soil fumigant for the nursery, was going to serve as the control for the study. The TE-
3 fumigant was going to be studied to see how it affects the performance and growth of the pine
seedlings. The TE-3 fumigant was sprayed at three different application rates within the block:
250, 300, and 350lbs/ac. A map of the block was generated to show the boundaries of the
different fumigation treatments within the block. This block is known as block 1-5 in the nursery
and is characterized as a first year ground block. At this nursery, this means that pine seedlings
are grown every year for 3 years. Then after the three years, the block is planted with a cover
crop to replenish the nutrients back into the soil. These blocks are termed fallow. At the end of
the year, the fallow blocks are sprayed with the soil fumigant and then begins the three year
cycle again. For this study two families were being tracked. They were each sown in at different
densities. The family 181210.WL was sown at 89.3 seeds/linear bed foot and the family
111076.WL was sown at 92.1 seeds/linear bed foot.
4. 2
A GPS was used with predetermined points from the fumigation map to locate the outside
boundaries of each fumigation treatment on the ground. Flags were placed at these boundaries to
serve as reference points for putting in the sample plots. Three grids were placed on the ground
at random locations in each of the four fumigation treatments for each family making sure that
none of the sample plots were close to any of the boundaries lines. This made a total of 24
sample plots. Each grid is one foot wide by four feet long. A flag was placed at each sample plot
with a number so that it could be easily referenced back to if needed. Also the GPS location of
each point was taken during the installation of the sample plots so that they could be placed on
the fumigation map.
Germination and weed populations were measured on a weekly basis. Germination tracking for
the nursery began in week 17(week of 4/21/2014). The germination tracking for the study began
in week 21(week of 5/19/2014), which meant that the data from those previous weeks were
unavailable to show the changing amount of germination over a larger time frame. Germination
tracking consists of counting the number of seedlings within the grid. Also if there were any
seedlings that were lost from one week to another, that also needed to be counted and the cause
of loss if that could be determined. Weed tracking consisted of counting the number of weeds in
the grid as well as identifying the species. Once the weed was accounted for, it was pulled from
the grid to monitor the reoccurrence of additional weeds growing back. Each week the number of
seedlings in each sample plot was divided by the known density that the family was sown at to
give a germination rate for each plot and an average for the three plots was calculated for each
treatment for the family. Germination tracking lasted for six weeks where germination had
reached its peak and there was no need to continue this measurement.
After the six weeks of measuring germination, the plots were then measured according to the
nursery’s crop tracking methods and schedule. Crop tracking is the ringing of individual trees
and monitoring the growth over time. For this study, six trees were ringed in each grid. There are
12 rows of trees per bed. The common practice of ringing the trees at the nursery is ringing the
tree in the 1st, 3rd, 5th, 8th, 10th, and 12th row along a line that is relatively straight. The side of the
bed that is closest to the center pivot is where the measurements began with the first ringed tree.
This began in week 27(week of 6/30/2014) with measuring only height. Crop tracking was
conducted every two weeks adding diameter and bud set to the measurements in week 29(week
of 7/14/2014). Since the trees in the block were going to be top pruned to a height of 8 inches,
the last measurement needed to be recorded in week 32(week of 8/4/2014) before the top pruning
procedure occurred. Weed tracking was still being conducted the same way only now it was
measured every two weeks. A ruler was used to measure the height of the selected trees and a
caliper was used to measure the diameter at the root collar.
Materials
- 24 grids for sample plots
- 24 flags to mark plots
- GPS to locate points
- 144 chicken rings to mark selected trees(6 in each grid)
- Ruler
- Calipers
5. 3
Results
Over the six week period that germination tracking was measured, there was a distinct difference
between the fumigation treatments. For family 181210.WL, the lowest germination rate was
present in the Tri-Brom 80 treatment with 89.96% and increased as the concentration of TE-3
increased as shown in tables 1-4. As seen in figure 1, the treatments were separated by a few
percentages from one to another showing the positive correlation that as concentration of TE-3
increased, germination for this family increased. The sample plots in TE-3 at 350lbs/ac had a
germination rate of 101.53% in week 26.
Family 111076.WL showed different characteristics for germination tracking. The treatment that
had the lowest germination rate was TE-3 at 250/lbs/ac with 94.82%. The treatment that had the
highest germination rate with 102.79% was TE-3 at 300lbs/ac as shown in Figure 2. The sample
plots in this treatment began with a germination rate over 100% when germination tracking
started.
There were very few weeds that came up during the germination tracking period. Shown in
tables 1-4 there were a total of five weeds from all the sample plots combined over the six week
period. No sample plot had more than one weed during germination tracking. Three of the five
weeds were black willow seedlings, which are very common at this nursery. The other two
weeds present were nutsedge. It is also important to note that sample plot #10 in the TE-3 at
350lbs/ac had numerous amounts of crabgrass near the grid. This was removed in week 24 by
handweeders. Since there were a low number of weeds through the germination tracking phase,
no visual was necessary to show the difference between the fumigation treatments.
Crop tracking showed closer results between the different treatment methods. Shown in figure 3,
family 181210.WL had the highest height at the end of week 32 with 6.5 inches for the Tri-Brom
80 treatment method.TE-3 at 250lbs/ac had an average height of 6.3 inches. TE-3 at 350lbs/ac
reached an average height of 5.8 inches and TE-3 at 300lbs/ac was the lowest with 5.7 inches.
Shown in figure 5, diameter measurements for this family showed the Tri-Brom 80 treatment
method had the highest average diameter of 3.1mm at the end of week 32. TE-3 at 250lbs/ac
reached an average diameter of 2.8mm and the other two TE-3 treatment methods reached an
average diameter of 2.7mm. The height and diameter growth for each tree in family 181210.WL
is shown in tables 5-8.
Height for family 111076.WL showed slightly different results. Shown in figure 4, the highest
average height at the end of week 32 was 6.5 inches for the Tri-Brom 80 treatment method. TE-3
at 350lbs/ac had an average height of 6.1 inches. TE-3 at 250lbs/ac reached an average height of
4.8 inches and TE-3 at 300lbs/ac was the lowest with 4.6 inches. Shown in figure 6, the highest
average diameter at the end of week 32 was 2.9 mm for TE-3 at 350lbs/ac treatment method. Tri-
Brom 80 had an average diameter of 2.8 mm and the other two TE-3 treatments methods had an
average diameter of 2.5mm. The height and diameter growth for each tree in family 111076.WL
is shown in tables 9-12.
6. 4
Discussion
Germination tracking showed that the TE-3 fumigant provided a higher germination rate than the
current soil fumigant at the nursery, Tri-Brom 80. The two highest application rates of TE-3 saw
the highest germination rate among the two families study. This may be due to the increased
elimination of disease and competition of weeds that TE-3 has over Tri-Brom 80 when the seed
is just breaking dormancy but there is not enough evidence to make a legitimate conclusion with
this little data.
Crop tracking showed that the trees in the Tri-Brom 80 treatment method were noticeably bigger.
One reason for this could be that many of the sample plots in this treatment method were located
in a low spot in the block. This is where the water and nutrient runoff would accumulate
providing more resources for the trees to grow bigger than other areas in the block. Diameter is
the more important measurement when compared to height. The seedling height can always be
changed by top pruning if they begin to grow too tall but diameter cannot be changed by any
mechanical methods. More investigation is needed to see if Tri-Brom 80 promotes larger tree
growth than TE-3 or if it was just because of where the sample plots were located in relation to
the low point in the block.
There are several improvements that could be made to this study. More data is always necessary.
More families could be measured instead of only two. Also having more sample plots throughout
the fumigation treatments helps in showing a better representation of what is out there.
Increasing the study to treating more than one block with the different soil fumigants across the
nursery could show how the fumigant performs at different locations. Also a big improvement to
this study would be including blocks from first year, second year, and third year ground to track
the performance of the seedlings with the effectiveness of the soil fumigant over time.
7. 5
Table 1: Shows the germination count and weedcount for each sampleplot over time for the Tri-Brom 80 treatment method. The average germinationrate for eachfamilyis calculated from the
three color-coded values. The blue is family181210.WL with a sow densityof 89.3 seeds/linear bed foot. The orange is family 111076.WL with a sowdensityof 92.1 seeds/linear bedfoot.
Tri-Brom 80
Sample Plots Average Germination Rate(%)/
Average Weeds
Average Germination Rate(%)/
Average Weeds1 2 3 22 23 24
Week 21
5/19/2014
Germ Tracking 82 68 76 93 83 89 84.35983576 95.91024249
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 22
5/26/2014
Germ Tracking 83 71 80 93 84 90 87.34602464 96.63409338
Weed Count 1 0 0 0 0 0 0.333333333 0
Weed Type Black Willow
Week 23
6/2/2014
Germ Tracking 84 70 81 93 85 90 87.71929825 96.99601882
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 24
6/9/2014
Germ Tracking 84 73 84 93 84 90 89.9589399 96.63409338
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 25
6/16/2014
Germ Tracking 84 75 84 93 84 91 90.70548712 96.99601882
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 26
6/23/2014
Germ Tracking 84 74 83 93 84 91 89.9589399 96.99601882
Weed Count 0 0 0 0 0 0 0 0
Weed Type
8. 6
Table 2: Shows the germinationcount and weedcount for each sampleplot over time for the TE-3 at 250lbs/ac treatment method. The average germinationrate for eachfamilyis calculated from
the three color-coded values. The blue is family181210.WL with a sowdensityof 89.3 seeds/linear bedfoot. The orange is family111076.WL with a sow densityof 92.1 seeds/linear bedfoot.
TE-3 at 250lbs/ac
Sample Plots Average Germination Rate(%)/
Average Weeds
Average Germination Rate(%)/
Average Weeds4 5 6 19 20 21
Week 21
5/19/2014
Germ Tracking 71 84 86 90 78 84 89.9589399 91.20521173
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 22
5/26/2014
Germ Tracking 73 88 86 91 84 84 92.19858156 93.73868983
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 23
6/2/2014
Germ Tracking 73 88 86 92 85 86 92.19858156 95.1863916
Weed Count 0 1 0 0 0 0 0.333333333 0
Weed Type Black Willow
Week 24
6/9/2014
Germ Tracking 76 87 87 92 86 85 93.31840239 95.1863916
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 25
6/16/2014
Germ Tracking 76 87 89 91 86 86 94.06494961 95.1863916
Weed Count 0 0 0 0 0 1 0 0.333333333
Weed Type Nutsedge
Week 26
6/23/2014
Germ Tracking 76 87 88 91 86 85 93.691676 94.82446616
Weed Count 0 0 0 0 0 0 0 0
Weed Type
9. 7
Table 3: Shows the germinationcount and weedcount for each sampleplot over time for the TE-3 at 300lbs/ac treatment method. The average germination rate for eachfamilyis calculated from
the three color-coded values. The blue is family181210.WL with a sowdensityof 89.3 seeds/linear bedfoot. The orange is family111076.WL with a sow densityof 92.1 seeds/linear bedfoot.
TE-3 at 300lbs/ac
Sample Plots Average Germination Rate(%)/
Average Weeds
Average Germination Rate(%)/
Average Weeds7 8 9 16 17 18
Week 21
5/19/2014
Germ Tracking 87 85 78 97 92 89 93.31840239 100.6152733
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 22
5/26/2014
Germ Tracking 87 88 79 97 93 92 94.81149683 102.062975
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 23
6/2/2014
Germ Tracking 89 87 80 98 93 93 95.55804405 102.7868259
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 24
6/9/2014
Germ Tracking 90 87 81 98 93 93 96.30459127 102.7868259
Weed Count 0 0 0 1 0 0 0 0.333333333
Weed Type Nutsedge
Week 25
6/16/2014
Germ Tracking 90 87 82 98 93 93 96.67786487 102.7868259
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 26
6/23/2014
Germ Tracking 90 87 81 98 93 93 96.30459127 102.7868259
Weed Count 0 0 0 0 0 0 0 0
Weed Type
10. 8
Table 4: Shows the germinationcount and weedcount for each sampleplot over time for the TE-3 at 350lbs/ac treatment method. The average germinationrate for eachfamilyis calculated from
the three color-coded values. The blue is family181210.WL with a sowdensityof 89.3 seeds/linear bedfoot. The orange is family111076.WL with a sow densityof 92.1 seeds/linear bedfoot.
TE-3 at 350lbs/ac
Sample Plots Average Germination Rate(%)/
Average Weeds
Average Germination Rate(%)/
Average Weeds10 11 12 13 14 15
Week 21
5/19/2014
Germ Tracking 94 89 77 89 86 97 97.05113848 98.44372059
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 22
5/26/2014
Germ Tracking 95 89 80 90 86 97 98.54423292 98.80564604
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 23
6/2/2014
Germ Tracking 94 89 80 90 85 98 98.17095931 98.80564604
Weed Count 1 0 0 0 0 0 0.333333333 0
Weed Type Black Willow
Week 24
6/9/2014
Germ Tracking 95 90 82 90 85 99 99.66405375 99.16757148
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 25
6/16/2014
Germ Tracking 95 91 85 90 85 99 101.1571482 99.16757148
Weed Count 0 0 0 0 0 0 0 0
Weed Type
Week 26
6/23/2014
Germ Tracking 95 92 85 90 85 99 101.5304218 99.16757148
Weed Count 0 0 0 0 0 0 0 0
Weed Type
11. 9
Figure 1:Shows the change ingermination rate for eachof the fumigation treatment over time for the family181210.WL. Week21 beganon5/19/2014.
80
84
88
92
96
100
104
Week 21 Week 22 Week 23 Week 24 Week 25 Week 26
GerminationRate(%)
Time
Family 181210.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
12. 10
Figure 2: Shows the change in germinationrate for eachof the fumigationtreatment over time for the family111076.WL. Week 21 beganon5/19/2014.
80
84
88
92
96
100
104
Week 21 Week 22 Week 23 Week 24 Week 25 Week 26
GerminationRate(%)
Time
Family 111076.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
21. 19
Figure 3: Show the change inheight over time for eachof the fumigation treatment methods for family181210.WL. Week 27 beganon6/30/2014.
0.0
0.6
1.1
1.7
2.2
2.8
3.3
3.9
4.4
5.0
5.5
6.1
6.6
7.2
7.7
8.3
8.8
9.4
27 29 31 32
Hieght(in)
Week
Family 181210.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
22. 20
Figure 4: Show the change inheight over time for eachof the fumigation treatment methods for family111076.WL. Week 27 beganon6/30/2014.
0.0
0.6
1.1
1.7
2.2
2.8
3.3
3.9
4.4
5.0
5.5
6.1
6.6
7.2
7.7
8.3
27 29 31 32
Hieght(in)
Week
Family 111076.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
23. 21
Figure 5: Show the change in diameter over time for eachof the fumigation treatment methods for family181210.WL. Week 27 beganon 6/30/2014.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
29 31 32
Diameter(mm)
Week
Family 181210.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
24. 22
Figure 6:Show the change inheight over time for eachof the fumigation treatment methods for family 111076.WL. Week27 beganon6/30/2014.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
29 31 32
Diameter(mm)
Week
Family 111076.WL
Tri-Brom 80
TE-3 at 250lbs/ac
TE-3 at 300lbs/ac
TE-3 at 350lbs/ac
25. 23
References
Carpenter, J. The Importance of Soil Fumigation: Nursery Crops. , 1-10. June 2013 Retrieved, from
http://croplifefoundation.files.wordpress.com/2012/12/nurserycrops-2013.pdf
Reliable Process for Planning and Management of Soil Fumigation. Weyerhaeuser Company Southern
Regeneration. , 1-58. May 13, 2014.
TriEst Ag Group, Inc. (2012, May 6). TE-3 Fumigant. [Material Safety Data Sheet].
TriEst Ag Group, Inc. (2012, October 26). Tri-Brom 80. [Material Safety Data Sheet].
