Weed ManagementLawnCareIA2022
2/20/2022Managing the Nasty Weeds of Lawn CareRoch Gaussoin, Extension Turfgrass Specialist, University of Nebraska12Yellow nutsedgeTubers A perennial weed found in both cool‐ andwarm‐season turfgrasses Control is difficult as a result ofintensive system of rhizomes &tubers and tolerance to manycommon herbicides Tuber production in yellownutsedge is highly prolific Tolerates close mowing and competes forwater and nutrients Fast growing34 Viable tubers may remaindormant in the soil formultiple years and maysprout repeatedly Results of herbicidecontrol of yellownutsedge are ofteninconsistentInterference Between Kentucky Bluegrass(Poa pratensis) and Yellow Nutsedge(Cyperus esculentus) in a Home Lawn5Luqi Li and Roch GaussoinUniversity of Nebraska‐Lincoln61
2/20/2022TreatmentsUNL East Campus Turf Research FarmThree irrigation levels: No Irrigation 80% total ET replacement per week Irrigate 2 inch /plot/week regardless of precipitationThree fertility levels: No additional fertility 2 lbs N/M/year 4 lbs N/M/yearTwo plot types:Mowed at 3 inch weekly Polyculture ‐ Yellow nutsedge within Kentucky bluegrass Monoculture – Yellow nutsedge in bare soil78Polyculture Plot9101112Monoculture Plot2
2/20/2022Polyculture Plot13Aug 2017Monoculture Plot14Monoculture vs. Polyculture1516 6,700VS. 44,500tubers per 1000 sq ftSummary: The presence of an actively growing turf impedes tuber andshoot production of yellow nutsedge from 65 to 98 % The non‐irrigated plots had less yellow nutsedge than ET oroverwatered plots in mono‐ and polycultureFrom 8” diasoil core The non‐fertilized plots had less yellow nutsedge than theheavily fertilized plotsPolyculture Sample17Monoculture Sample183
2/20/2022Chemical StrategiesSulfentrazone Dismiss is the primary postemergence herbicide with sulfentrazone,although SUREPYC and Solitare (sulfentrazone quinclorac) have a similaramount Dismiss may also provide preemergence with postemergence control;only Echelon (prodiamine sulfentrazone) is labeled for preemergencecontrol Q4 Plus, Surge, SureZone and TZONE all contain sulfentrazone; labeled foryellow nutsedge suppression, not control Injury will appear within a few days of application. Rate will affect thelevel of control but not the speed of activity Surfactant is not required, nor recommended1920ImazosulfuronHalosulfuron Celero Add NIS at 0.25% (v/v) Repeat application 21 days after the initialapplication if needed Do not apply to moist or wet turf Do not apply to golf course putting greens SedgeHammer, ProSedge, SedgeMaster and others Many formulations require a surfactant SedgeHammer formulation already includessurfactant Injury will appear in about two weeks followingapplication2122UNL DATAMesotrione Tenacity Causes a bleaching effect on susceptible weeds Surfactant recommended Not labeled for creeping bentgrass Repeat applications recommended Safe at seeding23244
2/20/2022BentazonPyrimisulfan Basagran T/O Four‐ to six‐leaf stage of nutsedge growth Apply when the temperature is at least 75 F Add crop oil or a nonionic surfactant for best results Complete spray coverage is essential Repeat applications recommended Vexis Cool and warm season, including bentgrass, ½” Slow response (21‐28 days) Granular (shake and bake)25 Spot treating26Effect of application timing on yellow nutsedge control when Sedgehammer(1 oz/A) and/or Dismiss (4 oz/A) was applied on June 3 and/or July 15.Vexis Testing at UNL‐2020Control1 app 3 tiller 40 dait2X app 3 tiller 40dait 10dat (2nd)2728Rotating MOA’s for Resistance ManagementWhen to control yellow nutsedge: Yellow nutsedge herbicide control programs must be implemented early in theseason and in consecutive years As early as it is visible Resistance in yellow nutsedge has been reported (Tehranchian et al.,2015) Tubers are immature Rotate halosulfuron, imazosulfuron or pyrimisulfan (Group 2) withmesotrione (Group 27) or sulfentrazone (Group 14) or bentazon(Group 8) for postemergence yellow nutsedge control Controls/suppresses tuber formation Herbicides are more readily translocated to roots, rhizomes and tubers Sequential application Make a second application 3 or 6 weeks after the initial application Sequential application works better than single app for most herbicides Rotate modes of action29305
2/20/2022Prostrate knotweed Summer annual .sort of ultimate indicator weed for compacted, low O2 soils alleviate problem, minimize weed opportunity early germination and grass‐like seedling stage confuse ID and control post germination growth rate increases exponentially, creating adense mat of residue dead wire‐like stems persist through winter Once established, control is very difficult3132Preemergence ControlPostemergence Control Late fall (November or December)applications of isoxaben (Gallery,Isoxaben 75WG) Other preemergence herbicideswill work, but less effective thanisoxaben Late winter apps work, butspraying conditions may beunfavorable dead wire‐like stems persistthrough winter to ID hot spots It is difficult to predict exactlywhen prostrate knotweed mightgerminate, usually Feb/March inthe central US. 2,4‐D by itself will provide only fair control of prostrate knotweed 2,4‐D triclopyr (Turflon Ester, Ultra or Triclopyr 4) or dicamba(Banvel, Vanquish) provide excellent control. Other products thatcontain 2,4‐D and triclopyr include 4‐Speed XT, Chaser, Chaser 2Amine, Momentum FX2, Sure Power, Turflon II amine, and TZONE Combination products that contain 2,4‐D and dicamba (Trimec 992and SpeedZone) provide good control Hit it hard and hit it early3334Visual percent control of prostrate knotweed following treatment with Change‐Up. InitiatedApril 20, 2019.13 DAAMay 3Change‐Up (MCPA, fluroxypyrand Dicamba) Efficacy onProstrate Knotweed26 DAAMay 1641 DAAMay 3155 DAAJune 1468 DAAJune 27Spring and Summer, 2019Change‐Up21233542.5 A81.3 A81.3 A77.5 A72.5 ARelzar applied at 0.72 oz/AChange‐Up applied at 3 pt/AMeans with a different letter are significantly different at P 0.05366
2/20/2022ControlApril 20Day ofApplicationChange‐UpApril 20Day ofApplicationMay 1626 DAAMay 1626 DAAJune2768 DAAJune2768 DAA3738Table 2. Percent control of prostrate knotweed following treatment with Change‐Up applied at3 pt/A . Initiated July 12, 2019.14 DAAJuly 2522 DAAAugust 236 DAAAugust 1642 DAAAugust 2249 DAAAugust 29Summary64 DAASeptember13 Spring: Change‐Up reduced prostrate knotweed populations up to 41DAA Change‐up provided 70% control Make multiple applications if applying early in the spring to compensate forgermination post applicationChange‐Up292.5 A100 A100 A100 A100 A Summer: Knotweed control was increased when applied in thesummer100 A Change‐Up provided 100% control123Relzar applied at 0.72 oz/AChange‐Up applied at 3 pt/ATreatments with a different letter are significantly different at P 0.053940Is crabgrass a nasty weed? WSSA – most “common” weed ‐Crabgrass spp. (large, smooth andsouthern crabgrass) Resistance issues with long used chemistries (smooth; DNA’s)41427
2/20/20224344Why was 2018 an issue .PrecipitationChemical Controlreturn to norm PreemergenceSoils cooler than norm Apply before weeds germinate Very effective on annual weedscrabgrass growth flush PostemergencePreemerge conc. Apply to actively growing weeds Contact SystemicSoil temps were lower than normal in the spring4546When to apply preemergence herbicides Soil temperatures exceed 50‐55 F Max emergence occurs at 70 Occurs first: In landscape beds Thinned turfgrass Near sidewalks Usually, around April 15 (NE) Most turf stands Around May 1‐15 (NE) Better to apply early than late47488
2/20/2022Crabgrass Postemergence Weed ControlPreemergence Herbicide “efficacy” Herbicide uptake and translocation vary Less than adequate control Application rates are correct,so.? Death of the weed may be slow Mature weeds may not be controlled completely Hit them hard and early Reasons for “failure” Poor turf conditionsTough weedsHigh rainfall/irrigationNon‐Uniform applicationClimate variability4950Weed Control Options During EstablishmentDecreasing control Major focus on seedling safety Newer herbicides available to use at seeding Tenacity (mesotrione), Drive XLR8 (quinclorac), SquareOne (quinclorac carfentrazone),Quicksilver (carfentrazone) Sooner the better Lack of emphasis on weed control Interspecific weed and grass competition Herbicide efficacy may be more important than safety Even though damage to young seedlings occurs, overall turf cover may be increasedcompared to no treatment5152Organic/natural weed control optionsWeed Control Options in Seedings Preemergence Corn gluten meal Distiller grains Start Early Be Aggressive Tenacity (Mesotrione) PRE on bare soil Post over turfed areas Crab Broadleaves Nutsedge Drive XLR8 (Quinclorac) Anytime on TF 7 days prior and Post 28 days after emergence on KBG Crab broadleaves Postemergence multiple SquareOne (Quinclorac Carfentrazone) Post 7 DAE Crab Broadleaves Non‐selective multiple Quicksilver (Carfentrazone) Post Broadleaves53549
2/20/2022Materials and MethodsSpring Applications: May 4 and May 31, 2018 (4 weeks after initial treatment)Fall Applications: September 13 and October 5, 2018Selective postemergence trialProduct55RateN/AN/AIron X26.52% Iron HEDTA25.2 oz/MA.D.I.O.S.Sodium chloride NIS1 lb product/gallonICT HaloEugenol, Clove Oil10 oz/MFiesta Weed Killer26.52% Iron HEDTA12.6 fl oz/M or25.2 fl oz/MFiesta Weed Killer Xiameter OFX‐030926.52% Iron HEDTA and Silicon Adjuvant12.6 oz/MNatria Lawn Weed and Disease Control26.52% Iron HEDTA25.2 fl oz/MTrimec Classic2,4‐D4 pt/ABoraxBoric AcidSpray to runoffEcoSmart Weed & Grass KillerRosemary OilSpray to runoffAgraLawn Weed and Crab KillerCinnamonShake on foliage56Materials and MethodsConclusionsSpring Applications: May 4 and May 31, 2018 (4 weeks after initial treatment)Fall Applications: September 13 and October 5, 2018ProductActive Ingredient Trimec Classic was always numerically the top performer forboth trials Products containing iron HEDTA and ICT Halo often werestatistically as effective as Trimec ClassicRateUntreated CheckN/AN/AIron X26.52% Iron HEDTA25.2 oz/MA.D.I.O.S.Sodium chloride NIS1 lb productICT HaloEugenol, Clove Oil10 oz/MFiesta Weed Killer26.52% Iron HEDTA25.2 fl oz/MFiesta Weed Killer Xiameter OFX‐030926.52% Iron HEDTA and Silicon Adjuvant12.6 oz/MNatria Lawn Weed and Disease Control26.52% Iron HEDTA25.2 fl oz/MTrimec Classic2,4‐D4 pt/ABoraxBoric AcidSpray to runoffEcoSmart Weed & Grass KillerRosemary OilSpray to runoffAgraLawn Weed and Crab KillerCinnamonShake on foliageFiesta Weed Killer26.52% Iron HEDTA12.6 fl oz/M57 Iron X Fiesta Weed Killer (full rate or w/ Xiameter) Natria Lawn Weed and Disease Control When using most organics, multiple applications will berequired Unpublished UNL study showed significantly diminishedeffectiveness if no reapplication is made58Cost AnalysisProductRateOrganic glyphosate alternatives (non‐selective)Cost per 1000 sq. ft.Untreated CheckN/A‐‐Iron X25.2 oz/M 102.00A.D.I.O.S.ICT Halo (name changed to Branch CreekWeed Shield)Fiesta Weed Killer1 lb product/gallon 202.7410 oz/M 6.5825.2/12.6 fl oz/M 16.73/ 8.37Fiesta Weed Killer Xiameter OFX‐030912.6 oz/M 38.78Natria Lawn Weed and Disease Control25.2 fl oz/M 17.8559Active IngredientUntreated CheckTrimec Classic4 pt/A 0.61BoraxSpray to runoff 5.00/ 64 ozEcoSmart Weed & Grass KillerSpray to runoff 25/ 64 ozAgraLawn Weed and Crab KillerShake on foliage 23/ 2 lbFiesta Weed Killer12.6 fl oz/M 8.376010
2/20/2022Organic alternatives toglyphosate applied tohybrid bermudagrass incentral California(citrus oil) Results indicated that glyphosate,when compared with AA, is themore effective weed suppressionmethod. Although all three AA treatments(5%, 20%, and 30%) initiallydamaged weeds faster thanglyphosate, AA did not controlweeds for an extended period likeglyphosate. The 20% and 30% AA applicationsrequired 3 to 4 treatments forequivalent control to glyphosate.Credit: Maggie Reiter@maggie reiterUniversity of CaliforniaCooperative Extension(citric acid, clove oil)(fatty acid)(capric/caprylic acid)(20% acetic acid)(glyphosate)6162Turfgrass Weed Control for ProfessionalsOrganic weed control synopsis Pro’s Viable optionsavailable, withresearch ongoing Market or regulatoryniche productshttps://mdc.itap.purdue.edu/item.asp?Item Number TURF‐100 Con’s Product cost Labor cost Contact vs systemic More applications Selectivity Efficacy6364From ‐ Turfgrass Weed Control for Professionals2018 Turf Weed Control for Professionals, Now Available656611
2/20/2022Other resources:Contact Information http://www.mobileweedmanual.com/ Jim Brosnan, Ph.D. Roch Gaussoin rgaussoin1@unl.edu@rockinsince57Thank you!676812
Fiesta Weed Killer 26.52% Iron HEDTA 25.2 fl oz/M Fiesta Weed Killer Xiameter OFX‐0309 26.52% Iron HEDTA and Silicon Adjuvant 12.6 oz/M Natria Lawn Weed and Disease Control 26.52% Iron HEDTA 25.2 fl oz/M Trimec Classic 2,4‐D4 pt/A Borax Boric Acid Spray to runoff
W-253 2018 NORTH DAKOTA WEED CONTROL GUIDE Compiled by: Rich Zollinger Extension Weed Science Contributors: Mike Christoffers Research Weed Science, Weed Genetics Caleb Dalley Research Weed Science, Hettinger R&E Center Greg Endres Extension Area Agronomist, Carrington R&E Center Greta Gramig Research Weed Science, Weed Ecology Kirk Howatt Research Weed Science, Small Grains/Minor Crops
3.2 Chemical Weed Control 10 3.3 Thermal Weed Control 14 3.4 Biological Weed Control 15 4.0 Natural Areas Weed Management 16 4.1 Purpose 16 4.2 Limitations 16 4.3 Study Area 16 4.4 Weed Management Site Prioritisation 18 4.5 Weed Monitoring 20 4.6 Weed Prevention 22 4.7 Weed Control 24 4.8 Partnerships 28 5.0 Parks and Urban Landscaping
Introduction to Weed Science and Weed Identification . Definition of a Weed A plant growing where it is not wanted (Oxford Dictionary) Any plant or vegetation, excluding fungi, interfering with the objectives or requirements of people (European Weed Science Society)
A guide to spring weed control Spring weed control in established pasture There are three key steps to effective spring weed control in established pasture - timing, weed identification and product selection. 1. Timing One of the most common mistakes made with spring weed control is spraying too late.
control, weed control, weed control '. Of course there are other important tasks, but weed control is surely one of the most vital! It is important to achieve good weed control in the 1m2 around each seedling. However the amount of ground disturbance should be kept to a minimum as open ground is an invitation to fresh weed establishment.
Introduction Weed management has been identified in many surveys of organic growers and farmers as being their number one problem, often by over 80% of respondents. Good weed management is essential for a successful organic enterprise. However, the amount of detailed information on organic weed . Organic Weed Management: A Practical Guide .
weed dry weight and recordedhigher weed control efficiency in groundnut.The use of herbicide as a means of weed management is fast gaining momentum especially in groundnut cultivation. Herbicides are efficient in suppressing or modifying weed growth in such a way as to prevent interference with crop establishment (Kunjo, 1981).
Academic Phrasebank. Setting objectives –student tip “It is important that your chosen research question is clearly focused and well written; answering it must be achievable in the time available to you!” Your research question and the objectives to achieve it. Your research title Your dissertation title is important as it tells your reader what your dissertation is about ! Titles often .
