Herbicide Update. Great Lakes Turfgrass Short Course Jan 7 Mar 25 Wed nights Online. UNL Turfgrass Field Day July 22, 2015 Mead.

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1 Herbicide Update Zac Reicher Great Lakes Turfgrass Short Course Jan 7 Mar 25 Wed nights Online UNL Turfgrass Field Day July 22, 215 Mead New herbicides NuFarm Last Call (fenoxaprop, fluroxpyr, dicamba ChangeUp (MCPA, fluroxypyr, dicamba) Dow Defendor New formulations on the horizon likely 1

2 New herbicides PRE s plus seeding RLT Luqi update % Crabgrass control in August Effect of formulation and rate of Dimension on crabgrass control over two years (UNL, 214) (apps made late Apr fb late June) EW WSP c cd e c bc ab de ab ab a a a a ab a ab ab ab ab ab lbs AI/Acre Effect of watering in PRE s applied very early May in 211 in Mead, NE (UNL 211). % Crabgarss control 15 July No water Watered in LSD=32 Check=15% cover Effect of watering in PRE s applied very early May 212 in Mead, NE (UNL 212). % Crabgarss control 15 July No water Watered in LSD=2 Check=65% cover 2

3 Tough to control Smooth brome in thinned lawns Yellow nutsedge Sandbur Knotweed Control of smooth brome with applied on two week intervals in June or July and rated in Sept 213. % Control June Apps July Apps 8 oz/a X 2 apps oz/a X 3 apps Check (% cover ) (24%) (19%) Control of smooth brome with applied on two week intervals in May, June, or July and rated in Sept 214. % Control May Apps June Apps July Apps 8 oz/a X 2 apps oz/a X 3 apps 69 8 Check (% cover ) (96) Control of yellow nutsedge with Sedgehammer or applied on 3 June or 15 July, 213. % Control Rate/1 App date 9/17/213 6/6/214 Sedgehammer.3 oz June 3 ab 97 a Sedgehammer.3 oz July ab 55 bc Sedgehammer.3 oz June 3+July15 97 a 94 a.12 fl oz June 3 21 cd 36 cd.12 fl oz July cd 9 de.12 fl oz June 3+July15 33 c c Sedgehammer.3 oz June 3 97 a 98 a.12 fl oz July fl oz June 3 67 b 72 ab Sedgehammer.3 oz July 15 Untreated Check (32%) d (37%) e Control of yellow nutsedge with Sedgehammer or applied on 3 June or 15 July, 213. % Control Rate/1 App date 9/17/213 6/6/214 Sedgehammer.3 oz June 3 ab 97 a Sedgehammer.3 oz July ab 55 bc Sedgehammer.3 oz June 3+July15 97 a 94 a.12 fl oz June 3 21 cd 36 cd.12 fl oz July cd 9 de.12 fl oz June 3+July15 33 c c Sedgehammer.3 oz June 3 97 a 98 a.12 fl oz July fl oz June 3 67 b 72 ab Sedgehammer.3 oz July 15 Untreated Check (32%) d (37%) e Control of yellow nutsedge with Sedgehammer or applied on 6 June or 17 July, 214 % control Rate/1 App date 9/17/214 Sedgehammer.3 oz June 3 1 a Sedgehammer.3 oz July c Sedgehammer.3 oz June 3+July15 99 a.12 fl oz June 3 63 b.12 fl oz July c.12 fl oz June 3+July15 85 ab Sedgehammer.3 oz June 3 99 a.12 fl oz July fl oz June 3 75 ab Sedgehammer.3 oz July 15 Untreated Check (%)c 3

4 Sandbur control in late August from two applications made on 1 and 12 July, 213 % Sandbur Control Herbicide Rate/A 8/2/213 Blindside 6.5 oz 22bc South 14.4 fl oz 84a 2.8 oz 17bc 8 fl oz 1bc 8 fl oz 7c Speedzone 3 pt 39b MSMA (Target 6.6) fl oz 1a Untreated Check c Plants in check plot =8 Sandbur control in September from two applications made on 1 and 28 Aug, 214 % sandbur control Herbicide Rate/A 9/25/14 Blindside 6.5 oz a South 14.4 fl oz a 2.8 oz 8bc 8 fl oz c 8 fl oz 11b Speedzone 3 pt c MSMA (Target 6.6) fl oz 1a Last Call 4 pt/a c ChangeUp 3 pt/a c (+MSO) 64 fl oz c Untreated Check c Plants in check plot = 4.3 Last Call (NuFarm) = fenoxaprop, fluroxpyr, dicamba ChangeUp (NuFarm) = MCPA, fluroxypyr, dicamba Puncturevine control in September from applications made 24 July 214 % defoliation Herbicide Rate/A 9/12/14 Last Call 4 pt/a 67 ac ChangeUp 3 pt/a 23 bc Untreated Check c Last Call (NuFarm) = fenoxaprop, fluroxpyr, dicamba ChangeUp (NuFarm) = MCPA, fluroxypyr, dicamba Percent control of prostrate knotweed from applications made 2 May 214 (UNL 214) Trimec Classic 3 pt/a 24D + MCPA + dicamba Trimec Classic 4 pt/a 24D + MCPA + dicamba Escalade2 2.5 pt/a 24D + fluroxpyr + dicamba Untreated (actual cover) 4 June 18 July 65 a 7 ab 64 a 61 b a 97 a b (75) c (97) BDLV herbicide effects on buffalograss cover/greenup Roundup is best control for cool season weeds when buffalograss is dormant Not very effective on BDLV weeds though When can we apply broadleaf herbicides during the buffalograss transition from dormancy to green? Lawn height, Bowie buffalograss 7 herbicides Quinclorac 64 fl oz/a 2.1 fl oz/a 2,4 D 4 pt/a Trimec 4 pt/a Confront 1.5 pt/a OneTime 64 fl oz/a Speedzone 64 fl oz/a 7 Applications dates April 1 and 15 May 1 and 15 June 1 and 15 July 1 4

5 BDLV herbicide effects on buffalograss cover/greenup Preliminary data Surprisingly few instances of damage No serious damage Damage may show up weeks after application Avoid 2,4 D or Speedzone to be extra cautious on buffalograss Zac Reicher zreicher2@unl.edu 5

6 Seeding into PRE s Always risk herbicide damage when done intentionally What about emergency reseeding when PRE s accidently applied Can we control weeds PRE and seed? Effect of PRE s applied 4, 2, or weeks before interseeding with Turfco Triwave at Lochland CC in Hastings (UNL 212). Seeding into PRE s % Cover PRYE 11/5/ applied 4 WBS applied 2 WBS applied WBS LSD=NS Herbicides Dimension 2 and.5 lbs ai/a Barricade 65 and.75 lbs ai/a Untreated control Application dates (Spring 213) 4, 2, weeks before seeding (WBS) 2 weeks after seeding (WAS) Methods Triwave ¾ inch solid tines and dropseed Ryan power rake and dropseed Dropseed 6

7 Effect of herbicide on turf cover (averaged over seeding method and application timing, UNL 213) Effect of seeding method on turf cover (averaged over herbicide and application timing, UNL 213) % Turf cover Untreated Check Dimension 2EW.25 lb ai/a Dimension 2EW.5 lb ai/a Barricade 65 WDG.38 lb ai/a Barricade 65 WDG.75 lb ai/a TTF 6/24/13 TTF 7/22/13 KBG 6/24/13 KBG 7/22/13 LSD(.5) % Turf cover Triwave Aerifier 3/4 solid dropseed Ryan power rake dropseed Dropseed TTF 6/24/13 TTF 7/22/13 KBG 6/24/13 KBG 7/22/13 LSD(.5) Effect of seeding method and application timing on turf cover (averaged over herbicide, UNL 213) Effect of seeding method and application timing on turf cover (averaged over herbicide, UNL 213) % Tall fescue cover 22 July Triwave Aerifier 3/4 solid dropseed Ryan power rake dropseed 4WBS 2WBS WBS 2WAS Dropseed % Kentucky bluegrass cover 22 July Triwave Aerifier 3/4 solid dropseed Ryan power rake dropseed 4WBS 2WBS WBS 2WAS Dropseed LSD(.5) = 14 LSD(.5) = 13 7

8 Preemergence costs/a (dithiopyr) On On 2 4 2EW $21.24 $ $59. $59. WSP Labor $1/hour $16.67 $16.67 $16.67 $16.67 $33.33 $2/hour $33.33 $33.33 $33.33 $33.33 $66.66 Assumptions to keep the math easy Average 8- ft2 per lawn, so 5 lawns/a 2 mins/lawn so 3 lawns/hour.6 A/hour $1/hour = $16.67/A $2/hour = $33.33/A Buffalograss Low maintenance (AFTER ESTABLISHMENT!) Requires irrigation, fertilization, and aggressive weed control in first year of establishment like any other turfgrass Most overlook this part and stand failures quickly occur Herbicides during establishment? Better to apply earlier than later Depends on weed spectrum Drive Annual grasses and some broadleaves Yellow nutsedge and some grasses and BDLVS PRE/POST Crab and BDLVS Post for crab and BDLVS Effect of single applications of herbicides over seedling buffalograss (UNL 212) (primary weed was redroot pigweed) Effect of single applications of herbicides over seedling buffalograss (UNL 213) (primary weed was yellow foxtail) % Cover at 6WAE (Bowie buffalograss/weeds) 7 Weed LSD = 14 Weed LSD = 5 Weed LSD = 6 2 Turf LSD = 25 Turf LSD = 22 Turf LSD = 24 1 Applied at seeding Applied 2WAE Applied 4WAE Princep Caliber Princep Caliber Princep Caliber Untreated check % Cover (Bowie buffalograss/weeds) 7 Weed LSD = 5 Weed LSD = 3 Weed LSD = 26 2 Turf LSD = 22 Turf LSD = 2 Turf LSD = 13 1 Applied at seeding Applied 2WAE Applied 4WAE Princep Caliber Princep Caliber Princep Caliber Untreated check 8