sedge biology and control in warm-season turf tim r. murphy the university of georgia
TRANSCRIPT
Sedge Biology and Control in Sedge Biology and Control in Warm-Season TurfWarm-Season Turf
Tim R. MurphyTim R. Murphy
The University of GeorgiaThe University of Georgia
Taxonomy of Sedges
Order – Graminales Class – Angiospermae Subclass – Monocotyledoneae Family – Cyperaceae (grasses are in Poaceae) Problem Genera – Cyperus and Kyllinga
Purple Nutsedge – Cyperus rotundus Introduced, native to Eurasia S. East U.S., CA and AZ Ranked world’s worst weed Forms chains of
interconnected tubers Prefers medium to fine-
textured soils Highly adapted to compacted
soils
Yellow Nutsedge – Cyperus esculentus
Native to North America Found in all of U.S. Ranked 16th worst weed
in world Forms tubers Commonly found in
sandy soils Thrives in non-compacted
soils
Other Key Differences
How do nutsedges reproduce?
Seed - ?????– Research indicates seed production and viability is
very low
Tubers– The primary method of reproduction– Numerous buds per tuber
Yellow Nutsedge Tuber Biology
Begin to form at tips of rhizomes 4 to 6 weeks after plant emerges
80% located in top 6 inches of soil Counts as high as 4 to 12 million/acre Shade will decrease tuber production
Yellow Nutsedge Tuber Longevity
Longer as tuber burial depth increases 4 month half-life at 4 inches 6 month half-life at 8 inches 3 consecutive yrs of control reduced tuber density
85% In SC, 200,000 tubers/ac remained after 4
consecutive yrs of > 90% control in bermudagrass
Tuber Sprouting
Buds form new shoots
Yellow – 54 F.
Purple – 68 F.
Kyllinga species
Sedge family Annuals – seed Perennials - seed and rhizomes No tuber formation Thrive in wet soils Increasing in severity Lack of MSMA use??
Green (perennial) kyllinga
Sedge & Kyllinga Herbicides Basagran T/O - yellow, annual sedges, kyllinga Manage - yellow, purple, annual sedges, kyllinga Monument - yellow, purple, annual sedges,
kyllinga Katana & Battalion – in development MSMA/DSMA - yellow, purple, annual sedges,
kyllinga Image - yellow, purple, annual sedges, kyllinga Pennant - yellow, annual sedges & annual kyllinga
Research Data
Purple nutsedge (Cyperus rotundus)
Yellow nutsedge (Cyperus esculentus)
False green kyllinga (Kyllinga gracillima)
(Appreciation is extended to Dr. Fred Yelverton, NCSU for use of data slides)
Purple Nutsedge (Cyperus rotundus) Control
0
20
40
60
80
100
6 WAIT
% C
ontr
ol
Monument .35 oz
Monument .59 oz
Monument .35 oz +Bueno 6 1.33pt
Manage 1.27 oz
Image 2.67 pt
Rates are per acre. Trial initiated 6-21. Sequential applied 8-2.
91b
99a
85c
74d 74d
Purple Nutsedge (Cyperus rotundus) Control
0
20
40
60
80
100
14 WAIT
% C
ontr
ol
Monument .35 oz
Monument .59 oz
Monument .35 oz +Bueno 6 1.33pt
Manage 1.27 oz
Image 2.67 pt
Rates are per acre. Trial initiated 6-21. Sequential applied 8-2.
78bc
94a
63d69cd
63d
Purple Nutsedge (Cyperus rotundus) Control
0
20
40
60
80
100
14 WAIT
# Sh
oots
/FT
²
Untreated
Monument .35 oz
Monument .59 oz
Monument .35 oz +Bueno 6 1.33ptManage 1.27 oz
Image 2.67 pt
Rates are per acre. Trial initiated 6-21. Sequential applied 8-2.
92a
16bc
5c
40b 38b 35b
Untreated
Monument .35 fb .35 oz
Monument .59 fb .59 oz
Manage 1.27 fb 1.27 oz
Image 2.67 fb 2.67 pt
False Green Kyllinga (Kyllinga gracillima) Control
0
20
40
60
80
100
6 WAIT
% C
ontr
ol
Monument .47 oz
Monument .47 fb .47 oz
Manage 1.33 oz
Manage 1.33 fb 1.33 oz
Image + MSMA .5 + 2 lb ai
85 a
97 a
82 a 84 a87 a
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-7. Sequential applied 5-27.
False Green Kyllinga (Kyllinga gracillima) Control
0
20
40
60
80
100
16 WAIT
% C
ontr
ol
Monument .47 oz
Monument .47 fb .47 oz
Manage 1.33 oz
Manage 1.33 fb 1.33 oz
Image + MSMA .5 + 2 lb ai
99 a 99 a
64 b
99 a 99 a
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-7. Sequentials were applied 5-27.
Yellow Nutsedge (Cyperus esculentus) Control
0
20
40
60
80
100
6 WAIT
% C
ontr
ol
Monument .47 oz
Monument .47 fb .47 oz
Manage 1.33 oz
Manage 1.33 fb 1.33 oz
Image + MSMA .5 + 2 lb ai
100 a 98 a93 a
63 bc
35 d
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-13. Sequential applied 6-23.
Yellow Nutsedge (Cyperus esculentus) Control
0
20
40
60
80
100
6 WAIT
% C
ontr
ol
Flaz 1.5 fb 1.5 oz
Flaz 3 oz
Flaz 3 fb 3 oz
Sulfo 1.33 fb 1.33 oz
MSMA 2 fb 2 lb ai
80 ab
100 a98 a93 a
45 cd
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-13. MSMA seq applied 5-26, flaz seq applied 6-3, sulfo seq applied 7-28.
Yellow Nutsedge (Cyperus esculentus) Control
0
20
40
60
80
100
16 WAIT
% C
ontr
ol
Monument .47 oz
Monument .47 fb .47 oz
Manage 1.33 oz
Manage 1.33 fb 1.33 oz
Image + MSMA .5 + 2 lb ai
61 abc
30 bcd
69 ab
56 abc
19 cd
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-13. Sequential applied 6-23.
Yellow Nutsedge (Cyperus esculentus) Control
0
20
40
60
80
100
16 WAIT
% C
ontr
ol
Flaz 1.5 fb 1.5 oz
Flaz 3 oz
Flaz 3 fb 3 oz
Sulfo 1.33 fb 1.33 oz
MSMA 2 fb 2 lb ai
25 bcd20 cd
58 abc
81 a
39 a-d
Rates are per acre. All trts included 0.25% v/v NIS. Trial initiated 5-13. MSMA seq applied 5-26, flaz seq applied 6-3, sulfo seq applied 7-28.
Key Factors for Sedge Control
Make initial application when sedges are actively-growing (need good soil moisture)
Repeat the application MSMA – 7 to 10 days Basagran T/0 – 7 to 10 days Monument, Manage, Katana, Battalion, Image
– 4 to 8 weeks (when regrowth is noted)
Key Factors for Sedge Control
Be aware of rainfast periods Image - NA (water 1 to 7 d after) Monument – 3 hrs Manage – 3 to 8 hrs Basagran T/O – 4 hrs MSMA/DSMA – 24 hrs
Add adjuvant as per label.
Key Factors for Sedge Control
Map infestations Include MSMA in rotation plan, especially
for kyllinga Include Basagran T/O in rotation plan,
especially for yellow nutsedge
Key Factors for Sedge Control
Follow all approved cultural practices Eliminate drainage problems Don’t over-irrigate and create habitat
favored by sedges and kyllinga
Plan on a multi-year program Persistence will be required
Sedge control ratings for selected turfgrass herbicides. (From McCarty, Murphy and Yelverton)
HerbicideAnnual Sedge
Purple Nutsedge
YellowNutsedge
Annual Kyllinga
Green Kyllinga
Pennant G P G F-G P
Ronstar G P P F P
Basagran T/O G P G F-G F-G
Image G G P-F G G
Manage G G G G F-G
MSMA/DSMA G P-F F G G
Image + MSMA
G G-E G G G
Monument ?? G-E G G G-E
???QUESTIONS????
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