Turfgrass. Keys for Identification of Some Southern Turfgrass Diseases (prepared by G.E. Holcomb)

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1 Keys for Identification of Some Southern Turfgrass Diseases (prepared by G.E. Holcomb) I. Grass affected in distinct patches; yellow to brown in color. A. Patches about inches in diameter; leaf lesions present.. Dollar Spot B. Patches greater than inches in diameter; no leaf lesions present. 1. Ring or arc of lush growth or dead grass; mushrooms present or not.. Fairy Ring 2. No ring or arc of lush growth present; no mushrooms present. II. Grass not affected in patches. a. Grass often affected in streaks, with leaves matted; primarily on ryegrass overseeded on golf courses and Bermuda grass greens.... Pythium Blight b. Patches more or less circular, may enlarge to several feet; leaves rotted at the base, can be pulled easily from the leaf sheath... Brown (Large) Patch c. Affected areas irregular in shape, 8 24 inches in diameter (or larger) with a mixture of yellow and dead grass; roots are sparse, short and black; stolons may be rotted... Take all Root Rot A. Chlorotic spots and orange powder (spores that can be rubbed off) on leaves.... Rust B. Leaf spots present, but no orange powder present. 1. Leaf spots varying in size; occurring primarily on Bermuda grass and ryegrass.... Melting Out or Leaf Spot 2. Leaf spots oval to irregular in shape with brown borders and tan to gray centers; primarily on St. Augustine grass..... Gray Leaf Spot. Leaf spots reddish brown to brown surrounded by a yellow halo; primarily on centipede grass Anthracnose C. No leaf spots present. 1. Grass covered with an easily removed slimy or crusty growth... Slime Mold (not a disease) 2. Mottle, chlorosis or mosaic on leaves; on St. Augustine grass or centipede grass..... St. Augustine Decline or Centipede Mosaic (virus diseases caused by Panicum Mosaic Virus)

2 Fungicide Uses on Commercial Turfgrasses Fungicide Common Name a Brown patch Large patch Dollar spot Gray leaf spot Leaf spots / melting out Takeall root rot b Fariy ring Pythium blight azoxystrobin boscalid captan cyazofamid ethazole (etridiazole) fenarimol fludioxonil fluoxastrobin flutolanil fosetyl Al iprodione mancozeb mefenoxam metconazole myclobutanil polyoxin D c phosphites (various salts) propamocarb propiconazole pyraclostrobin c quintozene (PCNB) tebuconazole thiophanate methyl thiram triadimefon c trifloxystrobin triticonazole vinclozolin Algae

3 a Active ingredient. b Also, Ggg root decline, Bermuda decline and spring dead spot. c For disease suppression only.

4 Relative Efficacy of Various Fungicides Against Diseases of Turfgrass a Fungicide Common Name b Brown patch Large patch Dollar spot Gray leaf spot Leaf spots / melting out Takeall root rot c,d Fariy ring azoxystrobin 4 4 () 2 boscalid 4 Pythium blight 2 2 copper hydroxide mancozeb cyazofamid fenarimol 2 (2) fludioxonil fluopicolide propamocarb fluoxastrobin 2 flutolanil 4 fosetyl al 2 iprodione 2 4 mancozeb mefenoxam 2 metconazole 4 2 myclobutanil polyoxin D phosphites (various salts) 2 propamocarb 2 propiconazole (2) pyraclostrobin () 2 quintozene (PCNB) tebuconazole 4 thiophanate methyl triadimefon (2) trifloxystrobin 4 2 triticonazole 4 2 vinclozolin Algae 4

5 a Efficacy ratings are on a scale from 1 (inconsistent but performs well in some instances) to 4 (consistently good to excellent results) and are based on trials using commercial formulations of the fungicides, not the formulations readily available to homeowners. Ratings were compiled by Dr. Paul Vincelli and Dr. David Williams at the University of Kentucky from published reports over a period. Source: PPA 1 Chemical Control of Turfgrass Diseases 2011; b Active ingredient. c Also, Ggg root decline, Bermuda decline and spring dead spot. d Ratings within parentheses are for take all patch caused by Gaeumannomyces graminis var. avenae.

6 Fungicides for Use on Commercial Turfgrass Common Name Trade Name (example) Formulation(s) Rate(s) (per1,000 square feet) Comments FRAC Code azoxystrobin Heritage Heritage G Heritage TL 50% WG 0.1% G 8.8% L pounds 1 2 fluid 14 to 28 day interval; no more than.7 or 18.5 fluid per 1,000 square feet per 11 boscalid Emerald 70% WG For golf course use only. 14 to 28 day interval; no more than 1.1 per 1,000 square feet per 7 captan Captan 50% WP 80% WDG pounds pounds For use on golf courses and sod farms only. 7 to 14 day interval M4 Chlorostar, Chlorothalonil, Countdown, Daconil, Echo, Ensign, Equus, Initiate, Mainsail, Manicure 8.5% F 54% F 82.5 WDG fluid fluid 1 5 M5 cyazofamid Segway 4.5% F fluid No more than three applications or 2.7 fluid per 1,000 square feet per 21 etridiazole (ethazole) Terrazole 5% WP 2 4 For use on golf course tees and greens only. 10 to 14 day interval; no more than 10 per 1,000 square feet per 14 fenarimol Rubigan 11.6% L fluid No more than 2 fluid per 1,000 square feet per fludioxonil Medallion 50% WP No more than 1.5 per 1,000 square feet per 12 fluopicolide Stellar 5.7 pounds SC 1.2 fluid Pre mixed with propamocarb for control of Pythium. No more than two applications or 2.4 fluid per 1,000 square feet per. 4

7 Common Name Trade Name (example) Formulation(s) Rate(s) (per1,000 square feet) Comments FRAC Code fluoxastrobin Disarm 480 SC 0.25% G fluid pounds (see labels) 14 to 28 day interval; no more than 0.4 fluid per 1,000 square feet per 11 flutolanil Prostar 70% WP No more than 4.5 per 1,000 square feet per 7 fosetyl Al Chipco Signature Prodigy Signature 80% WDG 4 8 lawns! 14 to 21 day interval iprodione 26GT Chipco Iprodione Pro 2.% F 50% WP 8 fluid Not for use on residential lawns! no more than 5 fluid or 17.6 per 1,000 square feet per 2 mancozeb Dithane, Fore, Manzate, Penncozeb, Pentathlon, Protect 7% F 75% DF 80% WP fluid See label M mefenoxam Fenox Mefenoxam Subdue Ultra Flourish 1% G 21.% L 22.5% F 25.1% 45% WP fluid fluid fluid No more than three applications of mefenoxam per season 4 metconazole Tourney 50% WDG Do not use on Bermuda grass! No more than 4 pounds per acre per myclobutanil Eagle Hoist 20EW 40% WP fluid No more than 1.8 fluid or 7.2 per 1,000 square feet per phosphite (salts of phosphorous acid) Alude, Exel, Fosphite, Fungi phite, Helena Prophyt, Primera Magellan, Vital Phosphorous acid equivalent (lb/gal) fluid 2 fluid 4 6 fluid fluid Helena Prophyt for sod farms only; see label

8 Common Name Trade Name (example) Formulation(s) Rate(s) (per1,000 square feet) Comments FRAC Code polyoxin D zinc salt Endorse 2.5% WP see label 19 propamocarb hydrochloride Banol 66.5% L 1. 4 fluid No more than 12.5 fluid per 1,000 square feet per 28 propiconazole Banner, Dorado, Fathom, Headway, Honor Guard, Propensity, Propiconazole, Savvi, Spectator 14.% L 41.8% L fluid fluid No more than 16 or 5.8 fluid per 1,000 square feet per pyraclostrobin Insignia 20% WG No more than 5.5 per 1,000 square feet per 11 quintozene (PCNB) Glacier, Parflo, PCNB, Revere, Terraclor, Turfcide 10% G 8.% F 75% WP pounds fluid 7 16 See label 14 tebuconazole Torque 8.7% L 0.6 fluid For use on golf courses only! Bermuda grass may be sensitive. No more than six applications or.6 fluid per 1,000 square feet per. thiophanatemethyl 6, Allban, Cavalier, Quali Pro TM, T Methyl, Transom, T Storm 2% G 41.25% L 46.2% F 50% WP pounds 2 6 fluid 1 5 fluid 2 6 See label 1 thiram Defiant, Spotrete, Thiram 42.1% L 75% WDG fluid See label M triadimefon Bayleton 50% WP See label trifloxystrobin Compass 50% WDG No more than two to three sequential applications 11 triticonazole Trinity, Triton 19.2% L fluid No more than 6 fluid per 1,000 square feet per vinclozolin Curalan 50 EG 1 Not for use on residential 2

9 Common Name Trade Name (example) Formulation(s) Rate(s) (per1,000 square feet) Comments FRAC Code Touché lawns! 10 to 21 day interval; maximum of per 1,000 square feet per. Combination Products azoxystrobin propiconazole Headway Headway G 5.7% 9.5% L 0.1% 0.75% G fluid 2 4 pounds (see labels) See labels. 11 azoxystrobin Renown % 45% L fluid. 11 M5 propiconazole fludioxonil Instrata 29.9% 4.7% 1.2% L fluid M5 12 thiophanatemethyl Consyst Spectro 90 Peregrine Quali Pro TM/C 50% 16.7% WDG 72% 18% WDG M5 1 fluopicolide propamocarb hydrochloride Stellar 5.54% 55.4% SC 1.2 fluid For use on golf courses and sod farms only 4 28 fluoxastrobin Disarm C 2.44% 8.4% L fluid 11 M5 fluoxastrobin Disarm M 15.8% 25.6% L fluid See label. 11

10 Common Name Trade Name (example) Formulation(s) Rate(s) (per1,000 square feet) Comments FRAC Code myclobutanil iprodione thiophanatemethyl 26/6 TM IP 19.65% 19.65% L 1 4 fluid Not for use on residential lawns or commercial sod! No more than 14.5 fluid per 1,000 square feet per ; no more than six applications per 2 1 mancozeb copper hydroxide Junction 15% 46.1% DF 2 4 Do not apply in spray solution with ph less than 6.5 M M1 propiconazole Concert 2.9% 8.5% L fluid (see label) with apartments, dayc are M5 pyraclostrobin boscalid Honor 16.8% 11.2% WG For use on golf courses only! 11 7 thiophanatemethyl flutolanil SysStar 28.6% 51.4% WDG 2 See label. 1 7 trifloxystrobin triadimefon Armada Tartan 25% L 50% WP 1 2 fluid No more than two to three sequential applications 11 triticonazole Reserve 5% 40% L fluid M5