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New weed management tools for grazed pastures
New Weed Management
Tools for Grazed Pastures
Summer
Annuals
Patrick McCullough, Ph.D.
University of Georgia
August 8, 2013
-%#."$'
-/0'1+/2%&'
Winter Annual Weeds
•! Begin emerging when soil temperatures drop
below approximately 70 F,
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•! Can be controlled with preemergence herbicides
in fall,
•! Proper application timing is critical.
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-*"&5'3"$$%&6&%,,'
Sept. 1 to 15
Late Summer Management
•! Control Summer Weeds
Sept. 15 to 30
•! Promote Recovery From Stress or Disease
–! Redirect traffic
–! Modify cultural practices
Sept. 15 to Oct. 15
Dr. Patrick McCullough
Extension Weed Scientist
•! Plan Fall Preemergence Herbicides
!"#$%&'()*+,%&),-+.*%/01((23%
New weed management tools for grazed pastures
Preemergence Herbicides
pendimethalin
•! Trade Name: Prowl H2O (3.8SL)
•! Chateau (flumioxazin)
–! Family: Dinitroaniline
–! Alfalfa
–! Mode of action: Mitosis inhibition
•! Kerb (pronamide)
–! Legumes
•! Applications: 1.1 to 4.2 qt/acre
•! Prowl H2O (pendimethalin)
•! Maximum Use: 4.2 qt/acre per year
–! Grass pastures
•! Grazing restrictions: 45 days after treatment
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•! .//0+'12+3&(4+$+&%(
PRE s
–! 5#63"#(7##,-(%#"$+&12#(3"(#-21*0+-8(
–! )+%8(#&39%8('3&'#&2"12+3&(23('3&2"30(%#"$+&12+3&(
•! :&+2+10(;#"$+&12+3&(4+$+&%((
–! <"1*%"1--=((>>(23(?@A(-3+0(2#$/#"129"#((
–! ;33-#%"1--=((?@(23(?>A(-3+0(2#$/#"129"#(
–! :6(21"%#2+&%(%33-#%"1--(3&0BC(1//0+'12+3&-($1B(*#(,#01B#,(28"##(23(
639"(7##D-E(
Preemergence herbicides do not prevent germination.
Dinitroaniline Injury
pendimethalin on
zoysiagrass
Surflan on St.
Augustinegrass
Dr. Patrick McCullough
Extension Weed Scientist
Dimension on
bermudagrass
!"#$%&'()*+,%&),-+.*%/01((23%
New weed management tools for grazed pastures
Italian Ryegrass Control
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Life Cycle:
Problems in Turf:
-%#."$'
Dr. Patrick McCullough
Extension Weed Scientist
Common Name
Trade Name
benefin (PRE)
Balan
Control
G
imazamox
Raptor
G
metsulfuron
Cimarron
nicosulfuron +
metsulfuron
paraquat
Pastora
G-E
various
G
pendimethalin (PRE)
Prowl H2O
pronamide (PRE)
Kerb
G
sethoxydim
Poast
G-E
F
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New weed management tools for grazed pastures
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Common Name
Trade Name
!1-23"1(
Control
2,4-D (and combination products) various
P
•! F#2-9069"3&(
aminopyralid
Milestone
F-G
aminopyralid + metsulfuron
Chaparral
G-E
dicamba
Banvel, Clarity
G
metsulfuron
Cimaron, others
G
metsulfuron + 2,4-D + dicamba
Cimarron Max
nicosulfuron + metsulfuron
Pastora
E
picloram + fluroxypyr
Surmount
G
–! ;"1--B(7##,('3&2"30(
triclopyr
Remedy
F
–! !"#I+39-0B(9-#,(+&(M#0,('"3/-(1-(.''#&2(
triclopyr + fluroxypyr
PastureGard
G-E
–! GH'#00#&2(1'2+I+2B(3&(*"31,0#16(7##,-C(-3$#(%"1--B(
7##,(1'2+I+2B(J*18+1%"1--C("B#%"1--K(
•! L+'3-9069"3&((
G-E
Field pansy – 5 in, bloom
Viola rafinesquii
Winter annual
Sticky chickweed, 6 in., bloom
Cerastium glomeratum
Winter annual
Carolina geranium – 6 in., bloom
Geranium carolinianum
Winter annual
Corn speedwell, 5 in., bloom
Veronica arvensis
Winter annual
:210+1&(NB#%"1--(<3&2"30(
!1-23"1(O(L:P(
!1-23"1(O(QCRST(
80
100
Control (%)
Control (%)
100
P3928#"&(<"1*%"1--(<3&2"30(
60
40
20
!1-23"1(O(L:P(
80
60
40
3 MAT
1 MAT
20
0
!1-23"1(O(QCRST(
0
14
45
Days After Treatment
Dr. Patrick McCullough
Extension Weed Scientist
Seedling
Multi-Tiller
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New weed management tools for grazed pastures
!1-23"1(4"+10-(12(U;.(
!1-23"1(4"+10-(12(U;.(
Weed Species
Applications
Control*
2
1
1
2
1
2
2
1
Excellent
Excellent
Good
Excellent
Good
Good
Excellent
Excellent
Barley, Little
Carolina Geranium
Chickweed, Sticky
Corn Speedwell
Fescue, Rattail
Field Pansy
**Excellent = 90 to 100%, Good = 80 to 89%
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Number of
Applications
Crabgrass (young
1
Control
Weed Species
seedling)
Crabgrass
(multi-tiller)
Fescue, Rattail
Ryegrass, Italian
Excellent
2
Poor
1
2
Fair
Excellent
1
Excellent
**Excellent = 90 to 100%, Good 80 to 89%, Fair = 70 to 79%, Poor = 69% or less
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•! !#"-/#'2+I#(
–! F3,#(36(1'2+3&=((PB&28#2+'(19H+&((
–! 1$+&3'B'03/B"1'803"(O('803"-9069"3&(
–! U-#=((!3-2#$#"%#&'#(*"31,0#16(7##,('3&2"30(+&(%"1--#-(
•! P2"#1$0+&#(
–! 1$+&3'B'03/B"1'803"(O($#2-9069"3&(
•! .'2+I#(+&%"#,+#&2(+&(&#7(/"3,9'2-(
•! W+#7/3+&2(
–! N#V9I"1(JO(2"+'03/B"K(
–! 1$+&3'B'03/B"1'803"(O(+$1X1/B"(O($#2-9069"3&(
–! :&I3"1(JO($#2-9069"3&K(
–! L#7(Y3"$9012+3&(7+00(*#(1I1+01*0#(63"('92(-29$/(2"#12$#&2-(28+-(B#1"(
<12-#1"(T1&,#0+3&(<3&2"30(
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Active Ingredients
Rate
Perspective
aminocyclopyrachlor
+ chlorsulfuron
1.88 + 0.75
oz a.i./acre
Streamline
aminocyclopyrachlor
+ metsulfuron
1.88 + 0.6
oz a.i./acre
Milestone 2SL
+ Plateau 2AS
aminopyralid +
imazapic
1.88 + 1
oz a.i./acre
Treatments applied on April 29, 2010
Dr. Patrick McCullough
Extension Weed Scientist
100
Control (%)
Herbicide
Perspective
Streamline
Milestone + Plateau
80
60
40
20
0
34
209
Days After Treatments
!"#$%&'()*+,%&),-+.*%/01((23%
New weed management tools for grazed pastures
59'D83"&(!01&21+&(<3&2"30(
Control (%)
100
Perspective
Streamline
White Clover Control 5 Days After Treatment
June 2010 UGA Griffin
Milestone + Plateau
80
60
40
20
0
34
209
aminocyclopyrachlor
Days After Treatments
Catsear Dandelion 5 Days After Treatment
June 2010 UGA Griffin
Untreated
Streamline at 4.75 oz/acre + NIS
(aminocyclopyrachlor + metsulfuron)
90 Days After Treatment
Pastora 1.5 oz/acre + Roundup at 8 fl oz/
acre + NIS 0.25% v/v
56 DAT
Dr. Patrick McCullough
Extension Weed Scientist
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New weed management tools for grazed pastures
1/==/#'3%&=)8*4&*,,'"#'>&"?#@'>('
1/==/#'3%&=)8*4&*,,'"#'>&"?#@'>('
:*5'HI@'BCCD'
:*5'HI@'BCCD'
Green under dormant zoysiagrass
Dr. Patrick McCullough
Extension Weed Scientist
Dormant zoysiagrass spot sprayed with glyphosate
!"#$%&'()*+,%&),-+.*%/01((23%
New weed management tools for grazed pastures
Water Quality Evaluation
•! Sampled 1 Liter of water from 20
locations,
•! Tested
–! Water hardness
–! pH
–! Turbidity
Upson
County
Spalding
County
Marion
County
Water Hardness
Water hardness is calculated from dissolved
Chatham
County
Sterling
County
Appling
County
Example: Soft Water
Mg+2
Ca+2
Ca+2
minerals, primarily Mg and Ca.
•! 60 to 120 = Moderately hard
glyphosate
•! 121 to 180 = Hard
•! 181 or higher = Very Hard
Dr. Patrick McCullough
Extension Weed Scientist
Ca+2
Mg+2
Mg+2
glyphosate
!"#$%&'()*+,%&),-+.*%/01((23%
New weed management tools for grazed pastures
Example: Hard Water
Ca+2
Ca+2
Mg+2
Ca+2
Mg+2
Ca+2
Ca+2
Mg+2
Ca+2Mg+2
Ca
Mg+2
Ca+2
Mg+2
+2
Not
glyphosate
Mg+2
glyphosate
Mg+2
Mg+2
Ca+2
Mg+2
+2
Ca+2 Mg
Mg+2
Mg+2
Mg+2
Mg+2
Ca+2
Mg+2
Turbidity and Suspended Solids
Location
Sterling
Tifton
Abbeville
Baxley
Chatsworth
Lafayette
Fitzgerald
Rome
Pooler
Carnesville
Jefferson Co.
Washington Co.
Atlanta
Baldwin Co.
Spalding Co.
Gainesville
Jefferson
Upson Co.
Marion Co.
Hardness (PPM)
205
154
143
139
129
121
84
73
64
59
55
51
39
38
34
25
17
15
4
Chatham County
Source: Waste Treatment Plant
•! Turbidity
–! Clarity of water samples
–! EPA Max level is 5.0 NTU
•! Total Suspended Solids
Location
Pooler
Marion Co.
Upson Co.
Fitzgerald
Spalding Co.
Sterling
Washington Co.
Carnesville
Atlanta
Baldwin Co.
Rome
Tifton
Jefferson
Baxley
Gainesville
Jefferson Co.
Lafayette
Chatsworth
Abbeville
TSS (PPM)
11.00
<3.99
<3.84
<3.4
17.00
<3.44
<3.70
<4.54
<5.04
<3.59
<5.17
<3.48
<4.54
<3.46
<4.31
<3.75
<3.57
<4.16
<3.4
Turbidity (NTU)
38
36
8
3
2
2
1
1
1
1
1
0
0
0
0
0
0
0
0
Dr. Patrick McCullough
Extension Weed Scientist
Location
Sterling
Fitzgerald
Rome
Tifton
Atlanta
Baxley
Jefferson
Abbeville
Lafayette
Chatsworth
Pooler
Baldwin Co.
Gainesville
Upson Co.
Spalding Co.
Jefferson Co.
Washington Co.
Carnesville
Marion Co.
pH
7.9
7.9
7.9
7.8
7.7
7.7
7.5
7.5
7.5
7.4
7.2
7.2
7.1
7.0
7.0
7.0
6.9
6.6
5.3