Download pdf - Weather - Turf Pathology, Plant Sciences, … collaboration between Dr. Brad Fresenburg (weeds), Dr. Bruce Barrett (insects), and myself (diseases) has produced a definitive, yet brief

OneSwingShouldWaittil’Spring

Weather

Bothbymeteorologicalandastronomicalstandards,fallisinforcetodaywiththearrivalofthefallequinox.Itsuredoesn’tfeellikeitthough,astemperatureshaveaveraged6-8degreesabovenormalininmuchoftheregionoverthelast7days,duetoastagnantjetstreamoverCanada.Asobviouslynoticed,photoperiodswillcontinuetogetshorteruntilthewintersolsticeonDecember22nd,whentheapproximately9.5hourdaylengthwillstarttoexpandonceagain.Withthecurrentheatwave,theshorterdaylength(currentlyjustunder11hours)hasaprofoundeffectonreducingstressoncoolseasonturfgrassesandputtingwarmseasonspeciessuchasbermudagrassandzoysiagrassdownfortheirwinter’snap.Someconcernshavebeenraisedoverpotentialcoolseasonseedlingdamagefromthehighheatandpotentialdiseaseactivity.Atthispoint,wehaven’tnoticedanyproblems,andlastweek’scooltemperaturesandrainsshouldstillbeaidingquickestablishment.Ifseedandfertilizerwereappliedprevioustoit,lastweek’srainswereampleenoughtogetseedofftoagoodstart…thatisiftheseeddidn’tfloatawayasmayhavebeenthecaseinColumbia.Precipitationtotalsareabovenormal,butvariableacrossthestate(0.6,1.18,2.62,and4.75inchesabovenormalinSpringfield,KC,STL,andColumbiarespectively).AttheMUturfresearchfarm,wehavebeenitchingtoseedafewnewareas,includingaperennialryegrassNTEPtrialandKentuckybluegrassplot,buttheweatherjusthasn’tallowedustogetinthefield.A3-dayraineventonSept.8-10dropped4.46inchesofrain,whichwasquicklyfollowedbyanadditional2inchesfromeventsonSept.14andSept.16.AsoggySeptemberisfollowingtheprecedentsetbyJulyandAugust.



QuickHits:

• Rust:AsamplefromaKentuckybluegrasslawnintheSpringfieldareawassubmittedlatelastweekwithaconsiderableamountofstemrust.Thisdiseaseisnormallymostsevereonyoungerturfgrassstands,andthosethatareimpactedbydrought.InlateMay,asignificantrustoutbreakwasalsoobservedinaKentuckybluegrasssportsfieldinColumbia.Rustisalsoconsidereda“lownitrogen”disease,soatthispointfertilizingwith1lbN/1000sqftwillhelpeitherKentuckybluegrassortallfescuerecover,potentiallywithouttheuseoffungicides.Iffungicidesaredeemednecessary,theQoIs(i.e.Heritage,Insignia)ortheDMIs(i.e.Bayleton,Banner)aresuggested.


• PestManagementforHomeLawnsBooklet:WantabitofMUexpertisein

yourpocketwhenmanagingeitheryourlawnoryourclient’s?Wanttotrainyourstaffonidentificationandbiologyofcommonlawnspeciesandtheirpests?Needaquickreferenceguideforfungicide,herbicide,orinsecticideactivity?AcollaborationbetweenDr.BradFresenburg(weeds),Dr.BruceBarrett(insects),andmyself(diseases)hasproducedadefinitive,yetbriefguideforlawnpestmanagement.Thisusefulresourceisapocket,orglove-box,sizedmanualwithadurablelaminatedcoverthatcanbewithyouonthegoandtaketheknocksofthecommonworkday.Wehopeyoucanmakegooduseofthisnewresource.Clickhereformoreinformation.


• Aerification/Seeding/Fertilization:Asmentionedinthepreviousupdate,thewindowisopenforfallrenovation,butwearegettingintothetailendofit.Althoughsteamy,therestofthisweekandweekend,priortonextweek’scooldownandpotentialrainevent,wouldbeaverygoodtimetoputdownsomesweatoncoolseasonturfgrassareas.Payattention,however,thatyouaren’tdoingmoredamagethangoodbycreatingcompactioninmuddyareaswithequipmentandtraffic.Asfarasfertilizationgoes,nowisthetimetofeedcoolseasonturfgrasses.Dr.BradFresenburghasdevelopedafantasticwebbasedapplicationthatwillhelpdeterminetheamountoffertilizerrequiredforacertainarea,includingalinktoaGPSreferencedareaestimator.Designedforhomeowners,butcanbeaveryhandytooltocheckyourownapplications.Checkitoutathttp://agebb.missouri.edu/fertcalc/.


Asthependulumswingstofall,largepatchsymptomsonzoysiagrasshaveflaredupagain.Lastweek’scooltemperaturesalongwiththeheavyrainfallinColumbia(asnotedabove)hasresultedinnumerouslargepatchoutbreaksattheMUresearchfarmandtwolawnsamplessentintotheClinic.Symptomscanappeardiffuseassmallinfectioncentersatthistimeofyear,orasthemoreregularpatchsymptom.Althoughnotasprominentasinthespring,thecharacteristicsymptomthisfallisanorangeflaggingofinfectedleavesonsymptomaticplants.Whenthepathogenisreallychugging,thisflaggingwillresultinaburntorange,orfiringsymptomonthemarginsofinfectedareas.Inamonthorso,dependingontheweather,zoysiagrasswillgodormantandsymptomswillbeindistinguishable.Now,however,istimetocomeupwithagameplanofhowto


dealwithbothfallandspringsymptoms.Scoutzoysiaareasanddeterminewhereoutbreaksareoccurring.Determineyourfungicidestrategy.Ifthreefungicideapplicationsareinyourplans,thecurrentsuggestionisanapplicationnow(orevenearlier)followedbyanotherlaterthisfall21-28dlaterinOctober,andanotherinearlyspring.Suggested2”soiltemperaturethresholdtargetsareafalltonear70FinSeptember(lowesthasbeen74FinColumbiahitlastweek)andaspringto50-55Finearlytomid-April.Basedonourresearch,atwoapplicationstrategyshouldincludeafallandspringapplicationaroundthesetwothresholds.Iflimitedtoasingleapplicationbasedonbudgetand/orclientwillingness,perhapsthebestmethodistosimplyscoutouttheaffectedareasnowandidentifytheproblem.Thenfollowupnextspringinearly–midApril(evenwhilethezoysiaisdormant)withanearlypreventiveapplication.Springlargepatchoutbreaks,particularlyduringwetMays,tendtocausethemostdevastatingdamageinthisregionoftheuppertransitionzone.Preventingthediseasefromgainingafootholdearlyinthespringcangetthezoysiathroughtheprimeinfectionperioduntiltheheatofsummerkicksinandthezoysiacanfendoffthepathogenonitsown.We’vedemonstratedfallapplications(clickheretoreadapreviousreport)aremoreerraticforspringcontrol,andmayrequirearescuetreatment.Ifonlyallowedasingleuseofthehammer,itwouldbewisetowaituntilspringtoswing.LeeMillerFollowonTwitter!@muturfpathLikeonFacebook!MizzouTurfgrassExtensionTurfgrassPathologist-UniversityofMissouri