Evaluation of Herbicide Programs for the Termination of ...mccc.msu.edu/wp-content/uploads/2017/08/MO_2015... · 14”; Pre-boot Late (May 16) 36”; Boot ---product/A--- --% Ann

Evaluation of Herbicide Programs for the Termination of Cover Crop

Species in the Spring

MaterialsandMethodsGeneral:IdenticalfieldexperimentconductedinColumbia,MOin2013,2014and2015PlantingDates:September11,2012;September11,2013andSeptember13,2014TerminationDates:EarlyAprilandearlyMayeachyearSeedingRates(lbs/A): Wheat 120

CerealRye 110Italianryegrass 25Oats 70CrimsonClover 30AustrianWinterPea 50HairyVetch 30CerealRye+HairyVetch 70+30

TillageRadish12/3/2013Columbia,Missouri ©KevinBradley,Univ.Missouri

Somespecieswillwinterkill….

InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaWheatCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100

4ptsGramoxone+1qtAatrex

4ptsGramoxone+1pt2,4-D

4ptsGramoxone

28ozsRoundup+4ozsCanopy

28ozsRoundup+1qtAatrex

28ozsRoundup+1ozSharpen

28ozsRoundup+16ozsClarity

28ozsRoundup+1pt2,4-D

28ozsRoundup

%VisualControl28DaysafterTreatment

EarlyTiming(earlyApril) LateTiming(earlyMay)

InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaCerealRyeCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100



4ptsGramoxone






28ozsRoundup



InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaAnnualRyegrassCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100



4ptsGramoxone






28ozsRoundup



InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaCrimsonCloverCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100



4ptsGramoxone






28ozsRoundup



InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaHairyVetchCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100



4ptsGramoxone






28ozsRoundup



InfluenceofHerbicideTreatmentsandApplicationTimingsontheControlofaAustrianPeaCoverCrop(resultsaveragedacross3years)

0 20 40 60 80 100



4ptsGramoxone






28ozsRoundup



g

g

g

f

bc

f

a

c-e

ab

ef

cd

de

a

a

0 20 40 60 80 100

Cerealrye

Cerealrye+hairyvetch

Wheat

Annualryegrass

HairyVetch

CrimsonClover

Austrianwinterpea

Early(earlyApril) Late(earlyMay)

%BiomassReduction28DaysAfterTreatment

*Barsfollowedbythesameletterarenotdifferent,LSD0.05

TheEffectofHerbicideApplicationTimingonBiomassReductionofVariousCoverCropSpecies

(resultssummarizedacross3yearsinMissouri)

early late early late

InfluenceofGlyphosate+2,4-DonBurndownofVariousCoverCrops

early latelate early

WinterWheatCerealRyeAnnualRyegrassCrimsonCloverHairyVetchAustrianWinterPea

latelateearly early late

c

c

bc

bc

ab

ab

a

a

a

0 20 40 60 80 100

Glyphosate

GramoxoneInteon

Glyphosate+Atrazine

Glyphosate+CanopyEX

GramoxoneInteon+Atrazine

Glyphosate+Sharpen

GramoxoneInteon+2,4-D

Glyphosate+2,4-D

Glyphosate+Clarity

%BiomassReduction28DaysAfterTreatment

InfluenceofSelectedHerbicideTreatmentsonCoverCropBiomassReduction

(resultsaveragedacross7covercropspeciesand3yearsinMissouri)

*Barsfollowedbythesameletterarenotdifferent,LSD0.05

Conclusions:Biomassreductioninresponse

toapplicationtiming

Theearlyapplicationtimingresultedinsignificantlygreaterbiomassreductionforallcovercropsexcept:

• AustrianWinterPea• HairyVetch

Early

Late

Conclusions:Mosteffectiveherbicideprogram

acrossallcovercropspeciesIngeneral,herbicideprogramsthatcontainedagrowthregulatorresultedinthemostconsistentcontrolacrossallcovercropspecies:BiomassReduction:

• Glyphosate+2,4-D:83%• Glyphosate+Clarity:85%

VisualControl:• Glyphosate+2,4-D:90%• Glyphosate+Clarity:90%

Glyphosate

Glyphosate+2,4-D

Allcovercropsshouldnotbeviewedequally…

©KevinBradley,Univ.Missouri

AnnualRyegrassLoliummultiflorum

a.k.a.“ItalianRyegrass”orjust“Ryegrass”

NOTAnnualRyeNOTCerealRye


Top15ResistantWeedsAccordingto#ofHerbicideModesofAction

444

55555

666

799

11

0 2 4 6 8 10 12

CommonLambsquartersDownyBrome

RedrootPigweedHorseweed

WildOatCommonRagweedPalmerAmaranthAnnualRyegrass

JunglericeWaterhempBlackgrassGoosegrass

AnnualBluegrassBarnyardgrassRigidRyegrass

©weedscience.org,Dr.IanHeap,11/2013

www.weedscience.org

Herbicide Resistance in Annual Ryegrass, 2015

Group 1 / ACCase Group 2 / ALS Group 9 / Glyphosate Group 10 / Liberty Group 15 / Chloroacetamides © Dr. Kevin Bradley

Glyphosate-resistantryegrassisnowoneofthemostsignificantweedproblemsinmanysouthernstates

PhotocourtesyofDr.LarrySteckel

InfluenceofHerbicideTreatmentsandTimingsontheControlofanAnnualRyegrassCoverCrop(Columbia,Missouri2013)

ApplicationTiming

HerbicideTreatment RateEarly(April2)5.75”;Tillering

Mid(April22)14”;Pre-boot

Late(May16)36”;Boot

---product/A--- --%Ann.RyegrassBiomassReduction28DAT--

RoundupPowerMax 36flozs 93 80 63RoundupPowerMax+2,4-D 36flozs+1pt 92 75 57RoundupPowerMax+Clarity 36flozs+1pt 87 65 64RoundupPowerMax+Sharpen 36flozs+1floz 90 76 54RoundupPowerMax+Aatrex 36flozs+1qt 91 81 55RoundupPowerMax+Canopy 36flozs+4ozs 88 79 47RoundupPowerMax+BasisBlend 36flozs+1.25ozs 83 78 56RoundupPowerMax 72flozs 90 78 65

GramoxoneInteon 4pts 78 77 44GramoxoneInteon+2,4-D 4pts+1pt 90 77 52GramoxoneInteon+Aatrex 4pts+1qt 87 82 54GromoxoneInteon+Lorox 4pts+24ozs 89 83 50GramoxoneInteon+Sencor+2,4-D 4pts+4ozs+1pt 90 87 60

Liberty 29flozs 35 50 34Liberty+Atrazine 29flozs+1qt 71 50 45

LSD0.05(treatmentsxtimings): ---------------------------------15-------------------------------

36flozsRoundupPowerMax+1qtAatrex

photostakenonJune1st

April2ndapplicationApril22ndapplicationMay16thapplication


EffectiveKillofCoverCropSpecies

•  Properherbicidetiming(lateMarch/earlyApril)isimportantformostspecies

•  Propertemperature/environmentbeforeandafterapplicationmaybejustasimportant

•  SpeciesthatarelikelytowinterkillincentralMissouri=tillageradish,sometimesoats

•  Speciesthathaveprovendifficulttocontrol=wheat,crimsonclover,Italianryegrass

•  Speciesthatarefairlyeasytocontrol=cerealrye,Austrianwinterpea,

Documents

Evaluation of Herbicide Programs for the Termination of ...mccc.msu.edu/wp-content/uploads/2017/08/MO_2015... · 14”; Pre-boot Late (May 16) 36”; Boot ---product/A--- --% Ann