Management of Turfgrass Weeds With New Herbicides Fred Yelverton, PhD Professor, N. C. State University AGCSA, Brisbane, Australia
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12 MAP
Poa annua Management on Desert Mountain Poa annua Bentgrass Greens Management on Putting Greens
Poa annua ssp. annua Incidence in Bentgrass TGR 0.5 TGR 0.375 TGR 0.25 Nontreated 10 21 21 75 0 20 40 60 80 100 % Poa annua (May 15) All rates are lbs ai/a applied every 4 wks Applications: 10-18, 11-15, 12-15, 2-8, 3-8, 4-20
www.turffiles.ncsu.edu Summary of Poa annua Control in Bentgrass Greens Paclobutrazol applied at 4 wk intervals is the most effective Poa annua control in bentgrass greens. Begin treatments in late summer/early fall when bentgrass growth resumes. Postpone treatments when bentgrass growth stops in winter and reapply when bentgrass growth resumes in late winter/early spring.
Sulfonylurea Herbicides (SUs) Metsulfuron (Manor/Blade) Chlorsulfuron (Corsair) Halosulfuron (Manage) foramsulfuron (Revolver) rimsulfuron (Tranxit) sulfosulfuron (Certainty) Trifloxysulfuron (Monument) Flazasulfuron www.turffiles.ncsu.edu
www.turffiles.ncsu.edu Other New Herbicides Bispyribac Velocity Carfentrazone (Quicksilver) Sulfentrazone (Dismiss) Fluoxypyr (in various 3-ways) Quinclorac (Drive) Mesotrione (Outplay)
Velocity 30 grams ai/a, 3 apps. April 4, 2005
www.turffiles.ncsu.edu Quinclorac (Drive 75DF) Couch, Perennial Ryegrass, Fescue, Bentgrass highly tolerant Must apply to actively growing weeds Will control summergrass and kikuyugrass
www.turffiles.ncsu.edu Quinclorac (Drive 75DF) A methylated seed oil is much better than other adjuvants. A crop soil concentrate is next best. Will not control crowsfoot or Poa annua.
Kikuyugrass (Pennisetum clandestinum)
Kikuyugrass (Pennisetum clandestinum) Perennial with rhizomes and stolons Drive 75DF (quinclorac) 1.1 kg/ha + 1.75 l/ha methylated seed oil or 2.3 l/ha crop oil concentrate Repeat application when kikuyugrass begins to regrow www.turffiles.ncsu.edu
Dandelion (Taraxacum officinale)
Postemergent Herbicides 3-ways including 2,4-D, MCPA, dicamba, bromoxynil, clopyralid, diflufenican. Clover and other legumes should use something with clopyralid in mix. Monument is excellent on bindii.
Silvery thread moss (Bryum argenteum)
% Control Silvery Thread Moss Control with Carfentrazone T&O and Daconil WeatherStik Applied Twice 100 21 20 34 LSD ( P =.05) 80 Quicksilver T&O 0.11 kg ai/ha 60 40 20 0 14-Aug 23-Aug 5-Sep Quicksilver T&O 0.22 kg ai/ha Quicksilver T&O 0.11 kg ai/ha + NIS* Daconil W.Stik 12.7 L/ha Check * NIS applied at 0.25% v/v Jul 24 and Aug 6, 2003 application dates
Mesotrione 0.28 kg ai/ha applied June 6 (5-7 lf crabgrass), photo taken June 14
% Control Postemergent Smooth Crabgrass Control 100 80 73bc 90a 83ab Mesotrione 0.37 60 60d Mesotrione 0.56 40 20 0 Late August Late September Rates are kg ai per hectare. Trts were applied 7-30 and included NIS.
% Control Postemergent Crowsfoot Control 100 80 96a 91a 78a-d 80abc Mesotrione 0.37 60 Mesotrione 0.56 40 20 0 Late August Late September Rates are kg ai per hectare. Trts were applied 7-23 and included NIS.
Sulfonylurea Herbicides (SUs) Interfere with acetolactate synthase (ALS Inhibitor) Readily absorbed by foliage and roots and translocated to meristematic region. Growth is inhibited in sensitive plants, followed by chlorosis and death of growing points. 10 to 21 days. www.turffiles.ncsu.edu
Characteristics of SU Herbicides Favorable environmental profile Low use rates Short-lived in soils (1/2 lifes 6-20 days Warm-season grasses tolerant, coolseason grasses sensitive High water solubilities Weed sensitivity varies greatly www.turffiles.ncsu.edu
www.turffiles.ncsu.edu SU Herbicides in Australia Critical weed management tools Removal of perennial ryegrass (spring transition) Control of sedges (particularly purple nutsedge and kyllinga spp. Other miscellaneous broadleaf weeds
Problematic Golf Course Weeds in Australia Poa annua Mullumbimby couch (Kyllinga) Purple nutsedge (Cyperus rotundus) Summer grass (Digitaria) Crows foot (Eleusine indica) Clover, Lawn burweed, Dandelion Paspalum, Eragrostis, Sporbolus www.turffiles.ncsu.edu
Poa annua control Sulfosulruon(left side) Monument (right side) Applied Nov 30, 2004 Photo Feb 24, 2005
www.turffiles.ncsu.edu Revolver 1.25L May 4, 2004 (25 WAT) Poa annua Control Revolver 1.25L Mar 4, 2004 (16 WAT) Poa annua Control
Monument + NIS 40g + 0.25% v/v Mar 4, 2004 (16 WAT) Poa annua Control Monument + NIS 40 g + 0.25% v/v May 4, 2004 (25 WAT) Poa annua Control
Post Control of Heavily Infested Poa annua With Sulfonylurea Herbicides 100 36 36 29 LSD ( P =.05) 80 60 40 Monument 0.33 oz* Monument 0.56 oz* Flazasulfuron 1.5 oz* Flazasulfuron 3 oz* 20 0 13-Jan 8-Mar 4-May 2 mo 4 mo 6 mo (after Nov 12, 2003 app.)
Rimsulfuron + NIS 70 g/ha + 0.25% v/v Applied Nov 30, 2004 Photos Apr 12, 2005 Check Poa annua and lawn burweed
Yellow Nutsedge (Cyperus esculentus)
Purple Nutsedge (Cyperus rotundus) www.turffiles.ncsu.edu
% Control Purple Nutsedge (Cyperus rotundus) Control 100 80 60 80b 86ab 86ab 96a 84ab 65c Monument 25g Monument 33g Monument 40g 40 20 Monument 25g + MSMA 2.2 kg ai/ha Manage 95g 0 2 WAIT Image 3.2 L/ha Rates are per hectare. Trial initiated 6-21. All treatments received sequential applied 8-2.
% Control Purple Nutsedge (Cyperus rotundus) Control 100 80 60 40 91b 97a 99a 85c 74d 74d Monument 25 g Monument 33g Monument 40g 20 Monument 25g + MSMA 2.2 kg ai/ha 0 6 WAIT Manage 95g Image 3.2 L/ha Rates are per hectare. Trial initiated 6-21. All treatments received sequential applied 8-2.
% Control Purple Nutsedge (Cyperus rotundus) Control 100 80 78bc 85ab 94a 63d 69cd 63d Monument 25 g Monument 33g 60 Monument 40g 40 20 0 12 WAIT Monument 25g + MSMA 2.2 kg ai/ha Manage 95g Image 3.2 L/ha Rates are per hectare. Trial initiated 6-21. All treatments received sequential applied 8-2.
Purple Nutsedge (Cyperus rotundus) www.turffiles.ncsu.edu
% Control Purple Nutsedge (Cyperus rotundus) Control with Single Application 100 91 a 80 60 40 20 0 12 WAT 44 b Monument 40g Manage 95g
Green Kyllinga (Kyllinga brevifolia) & False Green Kyllinga (K. gracillima)
% Control False Green Kyllinga (Kyllinga gracillima) Control 100 80 97 a 87 ab Monument 33g 60 40 20 0 56 b 18 WAT Manage 95g Image + MSMA 0.56 + 2.2 kg ai/ha
Antagonism with SU Herbicides?
% Control Purple Nutsedge (Cyperus rotundus) Control 100 Quicksilver 96 ml/ha 80 69 bc 78 ab Manage 45g 60 40 20 0 0e 22 WAIT 0 e 34 d Monument 25g Quicksilver + Manage 96mls + 95g Quicksilver + Monument 96ms + 25g Rates are mls or grams per hectare. Trial initiated 4-28.
Cool-Season Grass Tolerance to SU Herbicides
www.turffiles.ncsu.edu To Reduce Tracking Risk Spray after traffic has left for the day Water lightly (5 minutes) to remove dew. Should be done next morning prior to traffic.
Movement of SU Herbicides and Kerb WSP Following Irrigation on a 28 o Slope 5 4 3 2 1 Monument 0.33 oz/a* Monument 0.56 oz/a* Kerb WSP 3 lb/a* TranXit GTA 2 oz/a* Manor 0.5 oz/a* Revolver 17 oz/a Check 0 18-Mar Applied Dec 16, 2003 beside perennial ryegrass Irrigation: 2.5 on Dec 17 and 0.5 on Dec 18
Nontreated
trifloxysulfuron 17.4 g ai/ha
trifloxysulfuron 29.5 g ai/ha
rimsulfuron 35 g ai/ha
foramsulfuron 29 g ai/ha
metsulfuron 21 g ai/ha
pronamide 1.7 kg ai/ha
Monument application
trifloxysulfuron 29.5 g ai/ha
trifloxysulfuron 29.5 g ai/ha
trifloxysulfuron 29.5 g ai/ha
Dallisgrass (Paspalum dilatatum)
% Dallisgrass Control % Dallisgrass Control 1 YAIT 100 90 80 70 60 50 40 30 20 10 0 Herbicide Treatments Rev 60ml/100m2 fb Rev 1WAIT MSMA 30/100m fb Rev 60ml/100m 1WAIT MSMA 30ml/100m fb Rev 60ml/100m 2WAIT MSMA 30ml/100m fb Rev 60ml/100m 2WAIT fb MSMA 3WAIT MSMA 30ml/100m (2 apps) MSMA 30ml/100m (3 apps)
MSMA fb Rev 60ml/100m 2 2WAIT fb MSMA 3WAIT Photo: 12 WAIT
MSMA fb Rev 60ml/100m 2 2WAIT fb MSMA 3WAIT Photo: 1 YAIT
Certainty 87g/ha + MSMA 2.2 kg ai/ha + NIS 0.25% applied May 2 and June 13, 2005 Photo June 27
Smutgrass (Sporobulus indicus)
www.turffiles.ncsu.edu Smutgrass (Sporobulus indicus) Perennial with bunch type growth habit. Summer applications of atrazine at 1.1 kg ai/ha mixed with MSMA with a repeat in about 7-10 days provides good control. Expect some couchgrass discoloration.
Questions?