Herbicide Effects on Ryegrass Transition to Bermudagrass
Tim Murphy
The University of Georgia
Transition Issues
• Heat tolerance of ryegrass
• Renegade ryegrass
• Poa trivialis lives longer than expected
• Competition to bermudagrass
• Long-term effects on bermudagrass
• When do you accelerate transition?
Bermudagrass Growth
• Minimal root growth < 50 F. soil temp.
• Optimum root growth 75-85 F. soil temp.
• Shoot growth ceases < 55 F. air temp.
• Optimum shoot growth 80-95 F.
• Need night air temps. of mid-60s F.
• 100+ growing days
Chemical Aids for Transition
• Herbicides
• PGRs
• Delay application until bermudagrass is in active spring growth.
• No green-brown-green!!
• Need green-green
Atlanta Athletic Club Project
• ‘Tifway’ bermudagrass fairway
• Seeded 9/26/99 with 85/15 MarvelGreen/Laser mix
• Clipping height - 5/16 inch
• Irrigated as needed
Atlanta Athletic Club Project
• Herbicides and PGRs applied May 8, 2000
• 50/50 density of bermudagrass and ryegrass
• Overall turf quality, bermuda and ryegrass density recorded at 7, 14 and 30 DAT
Manor
0
1
2
3
4
5
6
7
8
9
10
Tur
f Q
ualit
y
0.33 oz. 0.5 oz. 1.0 oz. UTC
7 DAT14 DAT30 DAT
MANOR ON TRANSITION
0
20
40
60
80
100
7 14 30 7 14 30 7 14 30 7 14 30
Den
sity
CYNDA LOLPE
0.33 0.5 1.0 UTC
Sencor and Corsair
0
1
2
3
4
5
6
7
8
9
10
Tur
f Q
ualit
y
Sencor0.33 lb.
Sencor0.66 lb.
Corsair1.0 oz.
Corsair2.0 oz.
UTC
7 DAT 14 DAT 30 DAT
SENCOR ON TRANSITION
0
20
40
60
80
100
7 14 30 7 14 30 7 14 30
Den
sity
CYNDA LOLPE
0.33 0.66 UTC
CORSAIR ON TRANSITION
0
20
40
60
80
100
7 14 30 7 14 30 7 14 30
Den
sity
CYNDA LOLPE
1.0 oz. 2.0 oz. UTC
Kerb and Embark
0
2
4
6
8
10
Kerb 1.5lb.
Kerb 3.0lb.
Embark6.0 oz.
Embark8.0 oz.
UTC
7 DAT 14 DAT 30 DAT
Tur
f Q
uali
ty
KERB ON TRANSITION
0
20
40
60
80
100
7 14 30 7 14 30 7 14 30
Den
sity
CYNDA LOLPE
1.5 lb. 3.0 lb. UTC
EMBARK ON TRANSITION
0
20
40
60
80
100
7 14 30 7 14 30 7 14 30
Den
sity
CYNDA LOLPE
6.0 oz. 8.0 oz. UTC
CONCLUSIONS
• Manor - good to excellent bermuda tolerance, causes light green color, reduces ryegrass density, minimum rate is 0.5 oz.
• Corsair - excellent bermuda tolerance, not as effective as Manor, Kerb and Sencor in reducing ryegrass
CONCLUSIONS (cont.)
• Embark- excellent bermuda tolerance, no effect color, effectiveness on ryegrass is questionable, need research on repeat applications, earlier timings.
• Kerb - excellent bermuda tolerance, causes dark blue-green color, reduces ryegrass density, need research on lower rates, irrigation is critical
OTHER TRANSITION HERBICIDES
• TranXit (rimsulfuron)
• Revolver (foramsulfuron)
• Monument (trifloxysulfuron-sodium)
• Flazasulfuron (Katana)
• Sulfosulfuron (Battalion)
Monument Transition Project - 2001
• GA Station
• Perennial ryegrass – ‘Sunrise Primo’
• ‘Tifway’ bermudagrass
• 0.75 in. clip height
• 2 appl. – 5/16 and 6/14
• 25 gpa
• 0.25% v/v NIS with all herbicides except Kerb
Monument – One Appl. (5/16/01)
0123456789
10
Monument 0.1 oz.
Monument 0.3 oz
TranXit 4.0 Kerb - 1.5 UTC
Qua
lity 8 d
36 d
45 d
Monument – Two Appl. (5/16 + 6/14/01)
0123456789
10
Monument 0.1 oz
Monument 0.3 oz
TranXit 2 UTC
Qua
lity 7 d-B
15 d-B
30 d-B
MONUMENT – One Appl. (5/16/01)
0
20
40
60
80
100
15 36 44 15 36 44 15 36 44 15 36 44
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3 Kerb 1.5 UTC
Monument – Two Appl. (5/16 + 6/14/01)
0
20
40
60
80
100
7 15 30 7 15 30 7 15 30 7 15 30
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3 TranXit 2 UTC
Monument Transition Project - 2003
• GA Station• Perennial ryegrass – ‘Sunrise Primo’• ‘Tifway’ bermudagrass• 0.625 in. clip height• 4 appl. timings – 30, 60, 80 & 100% spring
green-up• 25 gpa, 0.25% v/v NIS with Monument
30% CYNDA Green-up (3/25/03)
0
20
40
60
80
100
2 mo 3 4 2 3 4 2 3 4 2 3 4
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3 Kerb 1.5 UTC
60% CYNDA Green-up (4/23/03)
0
20
40
60
80
100
1 mo 2 3 1 2 3 1 2 3 1 2 3
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3 Kerb 1.5 UTC
80% CYNDA Green-up (5/09/03)
0
20
40
60
80
100
4 wks 9 4 9 4 9 4 9
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3 Revol. 9.0
UTC
100% CYNDA Green-up (5/20/03)
0
20
40
60
80
100
4 wks 8 4 8 4 8 4 8
Den
sity
CYNDA LOLPE
MON 0.1 MON 0.3Revol.
9.0 UTC
Revolver Transition Project - 2002
• GA Station
• Perennial ryegrass – ‘Sunrise Primo’
• Common bermudagrass
• 0.625 in. clip height
• Single appl. – 5/10/02, 70% green-up
• 25 gpa
• NIS with TranXit, Manor and Monument
Revolver – Turf Quality
0123456789
10
REV 9.0 oz/a Manor 0.5oz/a
TranX 1.0oz/a
Monum 0.3oz/a
UTC
Qu
ali
ty
13 d 35 d 62 d
Applied 5/10/02
Revolver on Transition
0
20
40
60
80
100
35 62 35 62 35 62 35 62 35 62
Den
sity
CYNDA LOLPE
Rev 9 Man 0.5 TranX 1.0 UTC
Applied 5/10/02
Monum 0.3
BattalionTransition Project - 2002
• GA Station
• Perennial ryegrass – ‘Sunrise Primo’
• Common bermudagrass
• 0.625 in. clip height
• Single appl. – 4/23/02, 50% green-up
• 25 gpa
• NIS with Battalion, TranXit, and Manor
Battalion – Turf Quality
0
2
4
6
8
10
Batt 1.3 oz/a Kerb 2.0 lb/a TranXit 4.0oz/a
Manor 0.5oz/a
UTC
Qua
lity
14 d 30 d 52 d
Applied 4/23/02
Battalion on Transition
0
20
40
60
80
100
52 79 52 79 52 79 52 79 52 79
Den
sity
CYNDA LOLPE
Batt 1.3 Kerb 2.0 TranX 4.0 UTC
Applied 4/23/02
Manor 0.5
KatanaTransition Project - 2002
• GA Station
• Perennial ryegrass – ‘Sunrise Primo’
• Common bermudagrass
• 5/8 in. clip height
• Single appl. – 4/23/02, 50% green-up
• 25 gpa
• NIS at 0.25% v/v included
Katana – Turf Quality
0
2
4
6
8
10
Kat. 1.5 oz/a Kat. 3.0 oz/a Manor 0.5 oz/a UTC
Qua
lity
21 d 52 d 79 d
Applied 4/23/02
Katana on Ryegrass Injury
0
20
40
60
80
100
Kat. 1.5 oz/a Kat 3.0 oz./a Manor 0.5 oz./a
%
Inju
ry
6 d 14 d 21 dApplied 4/23/02
POST ANNUAL BLUEGRASS CONTROL IN OVERSEEDED BERMUDAGRASS
• Prograss – limited range of efficacy
• Battalion– rates, timing, efficacy research
• Velocity– Valent
– SLN in GA, FL, SC, NC
Velocity
• bispyribac-sodium, labeled in rice
• Use rates – 1.3 to 2.6 oz.product/ac
• inhibits ALS, no synthesis of branched chain amino acids
• not a sulfonylurea, but slow acting
• root and shoot absorbed, ½ life < 10 d
Velocity Projects - 2002
• GA Station
• Perennial ryegrass – ‘Sunrise Primo’
• ‘Tifway’ bermudagrass
• 0.625 in. clip height
• Irrigated site
Velocity– Perennial Ryegrass Injury
0
10
20
30
40
Velocity 0.7 oz. Velocity 1.4 oz. Velocity 2.8 oz
Rye
gras
s In
jury
26 d 40 d 48 d
Applied 4 wks after seeding, 3-lf ryegrass
Velocity– Annual Bluegrass Control
0
20
40
60
80
100
Velocity 0.7 oz. Velocity 1.4 oz. Velocity 2.8 oz
An
nu
al B
lueg
rass
Co
ntr
ol
27-Mar 7-May
Applied 4 wks after seeding, Oct. 23, 2001
Velocity– Perennial Ryegrass Injury
0
5
10
15
20
Velocity 0.7 oz. Velocity 1.4 oz. Velocity 2.8 oz
5 wks 7 wks
Applied 18 wks after seeding, Feb. 8, 2002
Velocity– Annual Bluegrass Control
0
20
40
60
80
100
7 WAT 8 WAT 11 WAT 12 WAT
An
nu
al B
lueg
rass
Co
ntr
ol
Velocity 0.7 oz. Velocity 1.4 oz. Velocity 2.8 oz
Applied 18 wks after seeding, Feb. 8, 2002
Velocity– Perennial Ryegrass Injury
0
5
10
15
20
Velocity 1.4 oz. Velocity 1.4 fb 1.4 oz.
Rye
gras
s In
jury
10 DAT 20 DAT 30 DAT 50 DAT
Applied 17 and 20 wks after seeding, Mar. 7 & Apr. 1, 2002
Velocity– Annual Bluegrass Control
0
20
40
60
80
100
20 DA-A 30 DA-A 50 DA-A 60 DA-A
An
nu
al B
lueg
rass
Co
ntr
ol
Velocity 1.4 oz. Velocity 1.4 fb 1.4 oz.
Applied 17 and 20 wks after seeding, Mar. 7 & Apr. 1, 2002
Accelerating Transition
Delay application until bermudagrass is in active spring growth.
Know 30 day forecastNo green-brown-green!! (on most sites)Need green-green
Bermudagrass Growth
When do you accelerate transition?Minimal root growth < 50 F. soil temp.Optimum root growth 75-85 F. soil temp.Shoot growth ceases < 55 F. air temp.Optimum shoot growth 80-95 F.Need night air temps. of mid-60s F.
Transition Options
• Slow – 4 to 6 wks– Kerb
– Embark (repeats)
– Cultural techniques
• Fast – 10 to 30 days– Katana
– TranXit
– Manor
– Revolver
– Monument
– Battalion
Health and vigor of bermudagrass is exceedingly important to a smooth transition.
www.georgiaturf.com
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