Downy Rose Myrtle
Herbicide Field Trial
by Elroy Timmer
Cooperators
SFWMD
Funding
By
BASF
DOW
Aquatic
Vegetation
Control,
Inc.
Vanquish and Krenite
The Best Two Treatments in 2007
100
90
80
70
60
Vanquish
2 qt.
50
40
Krenite
6 gal.
30
20
10
0
2 mo.
6 mo.
10 mo.
14 mo.
2007 Twenty Acre
Treatment
Vanquish at 2 quarts per
acre
Treatment by AVC for
SFWMD
adow Beauty
Gallberry
Bog Bachelor-Button
ohn’s Wort
Downyrose myrtle Treatments 2008
oz
plus
oz % Cntl
____________________________________________________________________
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Arsenal Powerline
Arsenal Powerline
Arsenal Powerline
Weedmaster
Weedmaster
Arsenal Powerline
Arsenal Powerline
Vanquish
Krenite
Vanquish
Arsenal Powerline
Weedmaster
Conquer oil 7.5% 32
32
24
Garlon 4 Ultra
32
24
32
Vanquish
Vanquish
Glyphosate
32
32
64
Krenite
Krenite
Krenite
64
64
32
32
112
64
768`
384
128
128
83
75
93
58
73
76
82
78
82
78
85
62
Downyrose myrtle Treatments
oz
plus
oz
%Cntl
______________________________________________________________________
13. Vanquish
32
Overdrive 4 oz
14. Vanquish
32
Overdrive 4oz
Vista
15. Garlon 4 Ultra 15% (37.5 gpa) (Cut Stump)
Labor 60 hours per acre
16. Garlon 3A
17. Garlon 4 Ultra
18. Vista
19. Garlon 4 Ultra 256 Vista
20. Milestone VM
21. Vanquish
32
Garlon 4 Ultra
22. Vanquish
32
Garlon 4 Ultra 128 Vista
42
70
92
89
384
248
42
42
14
128
42
80
82
57
81
28
90
88
Best Three Treatments on Downy
Rose Myrtle at 13 Months in 2009
93.5
93
92.5
92
91.5
91
90.5
90
89.5
89
88.5
88
Arsenal
Garlon 4
24
64
Vanquish
Overdrive
Vista
Vanquish
Garlon 4
32
4
42
32
128
Arsenal at recommended
use rate of 48 oz per acre
Arsenal
1% = 37.5 gpa
Arsenal 2 % = 18.75 gpa
Arsenal 3 % = 12.5 gpa
Arsenal max label rate 96 oz
Garlon 4 Ultra 15%
Cut Stump Treatment
•
•
•
•
37.5 gal per acre of oil and Garlon mix
Treated 1/100 Acre
5.625 Garlon 4 Ultra per acre
Per acre rate equals almost 3x label
rate
• 60 hours labor per acre plus
supervisors = approximately $1,400.00
• Approximately $900.00 herbicide
SFWMD TEST
• Plot Layout
• Types of plots
• Plant height influences
control
Example of Buggy path through tall 1/8 acre Downyrose myrtle
plot
15 feet
M
N
O
J
K
L
32 feet
10
ft. H
G
D
A
E
74
ft.
I
F
C
B
The 1/8 acre plots are (74 x74 ft). Rate was 100 gpa or 12.5 gal. per plot. The spray tip was calibrated at 1.32 gal per minute, it took 9.46
minutes to deliver 12.5 gallons. Plot was made up of 15 subplots A-O. Each subplot was treated with appropriate seconds to apply the proper
rate . A, C, D, F, G, I, J, L, M, and O required 51 seconds. B, E, H, K, and N required 12 seconds. Pump produced 1.32 gpm. A stock solution
of 33 gallons was used to treat two plots. The remaining 8 gallons was applied outside of the plot.
Example of 1/4 acre tall Downyrose myrtle plot, treated at 100
gpa
Buggy trail
A
C
Plots are 104 x 104 feet. Each subplot (example A and C) on each side of the 10 foot buggy trail is about 21 feet wide, by 15 feet (the length of the buggy).
After the buggy moved ahead, the buggy trail (B)(15 x 10 feet) was treated. Each pass though the plot required 12.5 gallons or 9.46 minutes. Both passes
required a total of 25 gallons and 18.92 minutes . Subplots such as A and C (21 x 15 feet) required 35 seconds while subplots such as B ( 15 x 10 feet)
required 11 seconds. A 33 gallon stock solution was used to treat each plot. The 8 gallon remaining solution was used to treat areas outside the plot. Each
pass through the plot required 7 stops at 15 feet each (7x15 = 105 feet)
Typical 1/8 acre short Downyrose myrtle plots. Treated by hand, red arrow lines depicts approximate path of
applicator
These 1/8 acre plots were divided in ½ to make treatment more manageable. They were treated at 50 gpa. or 6.25 gallons per
plot . Each half required 3.125 gallons and 2.36 minutes or 2 minutes and 22 seconds per ½ plot. The center of each plot was
marked for applicators perspective.
Example of hand tank plots (Vanquish) treated at 50 gpa
= 30
seconds
11
feet
12
feet
= 19
seconds
9 feet
squared
= 19
seconds
9 feet
squared
17 feet
squared
66 seconds
Each plot was measured and calculated for a percent of an acre. Example A, (11 x 112 feet = 132 square feet) or 0.003099174 of an
acre. It was calculated that 4.37 square feet could be treated per second. The square feet per plot was divided by 4.37 to equal
seconds per plot. (135 / 4.37 = 30 seconds). The tip used was a Spray Systems 2504 tip at about 20 psi. The spray tank is filled to
100 psi but spray tip delivers a constant pressure of 20 psi at the tip, via a regulator. A one gal stock solution was used. (1/50 of an
acre) Excess solution was used to treat surrounding Downyrose myrtle in the area.
Aquatic Vegetation Control
Is there any questions?
Thank you
Salvador Medina