Weed Control in Sod Production Fields Tim R. Murphy The University of Georgia

Weed Problems in Sod Intensive irrigation and fertility effects Effect of herbicides on sod Row crop weeds Common bermudagrass control Row crop vs. turf herbicides –Same ai and formulation

Cultural Control Avoid over-irrigation Install drainage if needed Properly mow on schedule –Will control most tall-growing broadleaf weeds Maintain pH and fertility Control insects and diseases Know weed spectrum

Hit or Miss Vs. Planned Program

PrePlant Weed Control Essential for common bermudagrass control –Will require one fallow season Roundup Pro –Still the best herbicide unless fumigation is used –Repeat applications will be needed

Roundup Rate and Bermudagrass Control DAT = Days after Treatment

Bermuda Control with Roundup – 1 yr.

Bermudagrass Control with Roundup (averaged across Tifway, Tifgreen, Tifdwarf, Ormond) Applied in late May, late June and Mid-August. Mowed at 1.0 inch. Rated June of year after application

“Newer” Sod Herbicides Envoy - centipedegrass Lontrel Confront Drive Manor, Blade Corsair

“Newer” Sod Herbicides Prompt 5L Label changes for Kerb

Envoy (Valent) SLN Georgia Label Centipede sod farms only Suppresses bermudagrass Controls annual grasses Not for use on seed fields Apply 3 wks after green-up Delay mowing 7 days before and after

Envoy - Bermuda Suppression Two applications at 34.0 fl. oz./acre Four applications at 17.0 fl. oz./acre 1st - 3 to 6 inch bermuda growth 2nd, 3rd, 4th - 3 to 3 inch bermuda growth Also controls most other annual grasses

Envoy Clethodim 0.94 lbs./gal. - EC 17.0 to 34.0 fl. oz./acre Add nonionic surfactant at 0.25% v/v

Bermuda Suppression with Envoy Established centipedegrass Natural common bermudagrass infestation Mowing height inch 1st applic. - June 23; 2nd applic. - July 15 Irrigated site Nonionic surfactant (NIS) added to Envoy

Bermudagrass Suppression -1998

Centipede Injury - Envoy

Sethoxydim (Vantage) - Centipedegrass Controls annual grasses Suppresses bahiagrass and bermudagrass No annual bluegrass control No nutsedge (nutgrass) control

Vantage - Centipedegrass No COC needed Established Seedling - 3 in. stolon growth Delay mowing 7 d before and after application

Vantage – Bahiagrass Suppression 2.25 pts./acre Delay mowing – 7 d before and after application Repeat application - 10 to 14 days Bahia must be actively-growing

Lontrel - DowAgrosciences 3.0 lb./gal. clopyralid Highly active on legumes and aster weeds Also controls curly dock, smartweed Rate 1/4 to 1.0 pt./acre High rate needed for smartweed Will not control dichondra (ponyfoot)

Turfgrass Tolerance to Lontrel

Confront - DowAgrosciences Triclopyr + clopyralid ( lbs./gal.) Amine formulation Active on wide range of broadleaf weeds Clopyralid highly active on asters and legumes Triclopyr controls chickweeds, henbit, mat lippia, lambsquarters, Va. Pepperweed, shepherdspurse

Turfgrass Tolerance to Confront

Confront Use 1.0 to 2.0 pts./acre Use on healthy, well established turf Delay reseeding for 3 weeks Mow seedling turf 2 to 3 times before application Needs 6 hour rain-free period

Drive - TopPro Quinclorac 75 DF Add crop oil concentrate (2.0 pts./acre) Labeled on tall fescue, Ky. Bluegrass, zoysiagrass, bermudagrass DO NOT use on centipedegrass or St. Augustinegrass

Drive - TopPro May be used before or after sprigging zoysiagrass Controls crabgrass (except smooth), white clover, hop clovers, speedwell, dollarweed Torpedograss - requires 2 to 3 applications Will not control goosegrass Use with extreme caution near tomatoes, bell peppers, etc.

Manor, Blade Metsulfuron 60 DF Excellent option for ‘Pensacola’ bahiagrass and broadleaf control in warm-season turfgrasses Do not use on bahiagrass Low rate - < 1.0 oz. product/acre Use only 0.25 to 0.5 oz/acre on centipede Use with nonionic surfactant

Corsair - Riverdale Chlorsulfuron 75% Used primarily for spot control of clumpy tall fescue in bermuda, zoysia, centipede, St. Augustine, Ky. Bluegrass – works slowly Avoid transition applications on centipede, zoysia, St. Augustine Repeat application in 60 d Add NIS at ¼ to 1/3 fl. oz./gallon of spray mix

Prompt - TopPro Pre-mix of bentazon+atrazine (2.5 lbs./gal. each) Labeled for bermuda, centipede, St. Augustine, zoysia (some injury to bermuda) Good option for yellow nutsedge, kyllinga, globe sedge, and numerous broadleaf weeds May be used 10 d after sprigging 2.4 pts./acre, repeat 7 to 10 d later for sedges

Kerb – Rohm & Haas Label expanded to include centipede, St. Augustine and zoysia Perennial ryegrass removal – apply at 50% green-up growth stage Poa annua control during winter months Needs rainfall or irrigation event (0.25 in.) within 24 to 48 hrs

TURFGRASS TOLERANCE TO HERBICIDES HERBICIDECENTIPEDEBERMUDA ATRAZINETD BENTAZONTT BENTAZON + ATRAZINETS-I MSMA/DSMAST SETHOXYDIMTS

TURFGRASS TOLERANCE TO HERBICIDES HERBICIDECENTIPEDEBERMUDA 2,4-DI-TT MCPPTT DICAMBAI-TT 2,4-D+MCPP +DICAMBAS-II-T MCPP+2,4-D +DICAMBAI-TT

TURFGRASS TOLERANCE TO HERBICIDES HERBICIDECENTIPEDEBERMUDA IMAZAQUINTT HALOSULFURONTT TRICLOPYR + CLOPYRALIDTI METRIBUZINNRT SETHOXYDIMTS

At-Sprigging Options Ronstar 2G - bermuda, zoysia, paspalum Ronstar 50WSP - bermuda Atrazine - centipede, St. Augustine, zoysia Simazine - centipede, St. Augustine, zoysia

Ronstar 2G and 50WSP - At Sprigging 2G to 150 lbs./acre 50WSP to 6.0 lbs./acre Apply immediately before or after sprigging Pre-sprigging (1 day before sprigging slightly safer than post-sprigging) Irrigate ASAP for best results

Atrazine and Simazine - At Sprigging Centipede, St. Augustine, zoysia Atrazine - labeled up to April 15 Simazine - labeled up to June 1 Do not apply within 30 days before lifting Apply 2 days after lifting sod on old beds - FL Apply 7 to 10 days after sprigging - FL

TOLERANCE OF NEWLY-SPRIGGED CENTIPEDEGRASS TO ATRAZINE AND SIMAZINE

The majority of herbicides used in turfgrasses for preemergence annual grass control are dinitroanilines and dithiopyr DNA’s Barricade Pendulum Surflan Balan Treflan Dimension Best used on established turf. Mitotic inhibitors. Relatively immobile in the soil Minimal use in sod fields

DNA and Dimension root inhibition pendimethalin on zoysiagrass Dimension on bermudagrass Surflan on St. Augustinegrass Swollen, club shaped roots

Sedge Herbicides - Turfgrasses Basagran T/O - yellow, annual sedges Manage - yellow, purple, annual sedges MSMA/DSMA - yellow, purple, annual sedges Image - yellow, purple, annual sedges Pennant - yellow, annual sedges 2,4-D - yellow, very poor activity

Tufted lovegrass

Tufted lovegrass in zoysia - Arkansas

Tufted Lovegrass – Eragrostis pectinacea Summer annual – reproduces by seed Difficult to control Ineffective herbicides –MSMAIlloxanPrincep –Fusilade T/ODriveKerb –AsuloxPennant

Tufted Lovegrass Herbicide Options –Atrazine, 1.5 lbs. ai/acre Pre (April) fb 6 wks later - > 95% –Oxadiazon, 2.0 lbs. ai/acre Pre (April) fb 10 wks later - > 65% –Acclaim Extra, 32 fl. oz./acre Late June – 90% control

Tufted Lovegrass Herbicide Options –Vantage, 1.0 pt./acre Late May - > 90% control –Envoy, 1.0 pt./acre Late May - > 90% control –Roundup Pro, 10.0 fl. oz./acre Early July – 100% control

UGA Turf Weed Science Web Page weed species 30 popular articles UGA turf weed science recommendations links to herbicide labels, MSDS

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