Nutsedge Cont

Richard Smith & OlFarm Advisor, MonFarm Advisor, MonCounties

trol in Onions

leg Daugovishterey & Venturaterey & Ventura

11ss

MetamMetam DacthalDacthalP fP f LoLoParaquatParaquat

RoundupRoundupSharkShark

PrefarPrefar

preemergencepreemergenceto weedsto weeds

LoLoProwProwNortronNortron

ScytheScythe to weedsto weeds

2007 and 2008 Registr2007 and 2008 Registr

GoalGoal

stst true leaftrue leafGoal TenderGoal Tender

2nd true leafGoalGoalBuctrilBuctrilProwlProwlOutlookOutlookoopoop

NortronNortron

OutlookOutlookSelect MaxSelect MaxPoast Poast FusiladeFusilade

oopoopwl H20wl H20

Dual MagnuDual Magnu(4(4thth True LeaTrue LeaOctober, 200October, 200

rationsrations

Backgrou

Tuber (nuTuber (nu

nd Nutsedge

RhizomesRhizomesGrow 8Grow 8--14” deep14” deep

utlet)utlet)

Nutlet forming at Nutlet forming at end of rhizomeend of rhizome

nutletnutlet

O th l t hO th l t h•• Once the plant has Once the plant has developed more than 5 developed more than 5 l it b i tl it b i tleaves it begins to leaves it begins to form nutletsform nutlets

N t d tN t d t•• Nutsedge cannot Nutsedge cannot tolerate shadetolerate shade

•• Unfortunately onions Unfortunately onions do not provide do not provide sufficient shade to sufficient shade to inhibit the growth of inhibit the growth of nutsedgenutsedge

BackgBackg•• Both Outlook and DuBoth Outlook and Du

chloroacetamideschloroacetamides (m(mchloroacetamideschloroacetamides (m(m•• It needs to be applieIt needs to be applie

f t df t demergence of nutsedemergence of nutsedpostemergence activpostemergence activ

•• It It can delay tuber spcan delay tuber spof yellow nutsedgeof yellow nutsedge

•• It can cause tuber mIt can cause tuber m

roundroundual Magnum are ual Magnum are mitosis inhibitors)mitosis inhibitors)mitosis inhibitors)mitosis inhibitors)d prior to the d prior to the d it hd it hdge as it has no dge as it has no vityvityrouting and kill shoots routing and kill shoots

ortalityortality

Timing of NutsTiming of Nuts•• In 2006, 2In 2006, 2ndnd true leaf true leaf

Outlook and Dual MaOutlook and Dual MaOutlook and Dual MaOutlook and Dual Main Monterey Countyin Monterey CountyH i b th 200H i b th 200•• However, in both 200However, in both 200emerged prior to theemerged prior to the

hi h did t ll Ohi h did t ll Owhich did not allow Owhich did not allow Oprior to nutsedge emprior to nutsedge em

•• Both of these materiBoth of these materiprior to the emergenprior to the emergeneffectiveeffective

sedge Controlsedge Controlapplications of applications of

agnum were effectiveagnum were effectiveagnum were effective agnum were effective

07 d 2008 t d07 d 2008 t d07 and 2008, nutsedge 07 and 2008, nutsedge e 2e 2ndnd true leaf stage true leaf stage O tl k t b li dO tl k t b li dOutlook to be applied Outlook to be applied

mergencemergenceals need to be applied als need to be applied

nce of nutsedge to be nce of nutsedge to be

2007 Nutse2007 Nutse•• In 2007 Outlook (DimIn 2007 Outlook (Dim

registeredregistered inin CalifornCalifornregistered registered in in CalifornCalifornonionsonions

edge Trialsedge Trialsmethenamidmethenamid--p) was p) was nia for use onnia for use on dry bulbdry bulbnia for use on nia for use on dry bulb dry bulb

2007 Nutse2007 Nutse•• Yellow nutsedge wasYellow nutsedge was

true leaf stage in 200true leaf stage in 200true leaf stage in 200true leaf stage in 200•• We needed to find a We needed to find a

workworkworkwork•• Three strategies testThree strategies test

1) 11) 1stst true leaf applicatrue leaf applica–– 1) 11) 1stst true leaf applicatrue leaf applica–– 2) Burn back nutsedg2) Burn back nutsedg

apply Outlookapply Outlookapply Outlookapply Outlook–– 3) 3) Basagran evaluatioBasagran evaluatio

edge Trialsedge Trialss emerged by the 2s emerged by the 2ndnd

070707 07 way to make Outlook way to make Outlook

ted:ted:ationsationsationsationsge with acid fertilizer then ge with acid fertilizer then

onsons

Test plotTest plotTest plot Test plot

April 18, 2007April 18, 2007

Grower Acid FertilizerGrower Acid Fertilizer Grower Acid Fertilizer Grower Acid FertilizerApplicationApplication

•• At the 2At the 2ndnd true leaf true leaf stage stage nutsedge nutsedge gg ggwas well developedwas well developed

Heavily InfeHeavily Infe

TreatmentTreatment MateriaMateria

77--77--00--77Fb Outlook 6.0Fb Outlook 6.0Fb Outlook 6 0Fb Outlook 6 0

35 gall35 gall7.0 oz7.0 oz7 0 oz7 0 ozFb Outlook 6.0Fb Outlook 6.0 7.0 oz7.0 oz

77--77--00--77FbFb Outlook 6.0Outlook 6.0

35 gall35 gall14.0 oz14.0 ozFbFb Outlook 6.0Outlook 6.0 14.0 oz14.0 oz

77--77--00--77Fb Outlook 6.0Fb Outlook 6.0

35 gall35 gall7.0 oz7.0 oz

Fb Outlook 6.0Fb Outlook 6.0 7.0 oz7.0 oz77--77--00--77FbFb Outlook 6 0Outlook 6 0

35 gall35 gall14 0 oz14 0 ozFbFb Outlook 6.0Outlook 6.0 14.0 oz14.0 oz

UntreatedUntreated --------

ested Siteested Site

al/Aal/A ApplicationApplication

onsonsPost 1 t. leafPost 1 t. leaf14 days later14 days later14 days later14 days later

onsonszz Post 1 t. leafPost 1 t. leafzz Post 1 t. leafPost 1 t. leafonsons

Post 2 t. leafPost 2 t. leaf14 days later14 days later

onsonszz Post 2 t leafPost 2 t leafzz Post 2 t. leafPost 2 t. leaf

--------

Post Acid Fertilizzer Application

77--77--00--7 7 Outlook 7.0 + 7.0Outlook 7.0 + 7.011stst true leaftrue leaf May 8, 2007May 8, 2007

Untreated Untreated Outlook 14.0 oz Outlook 14.0 oz11stst true leaftrue leafafter 7after 7--77--00--77

Weed Weed RROutlook After Outlook After

April 23; May 4; JuApril 23; May 4; JuApril 23; May 4; JuApril 23; May 4; Ju

7.0+7.0 oz 14.0 oz 7.0+1st true 1st true 2nd

RatingRatingAcid FertilizerAcid Fertilizerne 1; and August 9ne 1; and August 9ne 1; and August 9ne 1; and August 9

+7.0 oz 14.0 ozd true 2nd true

Nutsedge nutlets in the sNutsedge nutlets in the ssoil of the Outlook plotssoil of the Outlook plots

Nutsedge Tubers PNutsedge Tubers P

7.0+7.0 oz 14.0 oz 7.01st true 1st true 2nd

33Per 1000 cmPer 1000 cm33 of Soilof Soil

0+7.0 oz 14.0 ozd true 2nd true

Yi ld EYi ld EYield EvaYield Eval til tialuationsaluations

Onion Trial Onion Trial HeaHeaWith 7With 7

Yield Yield ––

7.0+7.0 oz 14.0 oz 7.0+1st true 1st true 2nd

avyavy InfestationInfestation77--77--00--77Tons/ATons/A

****

+7.0 oz 14.0 ozd true 2nd true

Comparison ofComparison ofComparison of Comparison of Yield Yield –– Mean Mean

7.0+7.0 oz 14.0 oz 71st true 1st true 2

Light vs HeavyLight vs HeavyLight vs Heavy Light vs Heavy Head Wt (lbs)Head Wt (lbs)

7.0+7.0 oz 14.0 oznd true 2nd true

2008 NutsedgeDehydratoDehydrato

e Control Trialor Onionsor Onions

Untreated 7-7-0-7+OutlookGoal Tender1st true leaf

77--77--00--7 + Outlook 7+77 + Outlook 7+777 77 00 7 Outlook 7 7 7 Outlook 7 7 11stst true leaf true leaf

77--77--00--7 + Outlook 7+77 + Outlook 7+7 7 7 77 00 7 Outlook 7 77 Outlook 7 7 2 2ndnd true leaftrue leaf

UntreatedUntreated 7-7-0-7 + Outlook 7+7 7-7-0-7 + Outlook 7+71st true leaf

Nutsedge WeedNutsedge Weedd Control Ratingd Control Rating

Yield ofYield ofYield of Yield of T/T/

OnionsOnionsOnionsOnions/A/A

Venturra Trials

Nutsedge emergNutsedge emerg

AA

AA

ged 5/21 to 6/26ged 5/21 to 6/26

AA

AAB

Nutsedge emergeM d O tMagnum and Out

AA

A A

ed after final Dual tl k li titlook application

A 7/11 (1 week)

B

8/7 (4 weeks)

Dual Magnum:nutsedge controlnutsedge control Untreated check

SummSumm

•• The Ventura trials shThe Ventura trials shof Dual Magnum for of Dual Magnum for ggnutsedge in onionsnutsedge in onions

•• It is unclear why therIt is unclear why therIt is unclear why therIt is unclear why theractivity of Dual Magnactivity of Dual MagnVentura CountyVentura CountyVentura CountyVentura County

•• No difference betweeNo difference betweewas observed in Monwas observed in Monwas observed in Monwas observed in Mon

marymary

howed good efficacy howed good efficacy controlling yellow controlling yellow g yg y

re is a difference inre is a difference inre is a difference in re is a difference in num and Outlook in num and Outlook in

en the two herbicides en the two herbicides nterey Countynterey Countynterey Countynterey County

SummSumm

•• Burning Burning back nutsedback nutsedprovides an opportuprovides an opportup ppp ppwork if nutsedge is ework if nutsedge is etrue leaf stagetrue leaf stagegg

•• There may be a yieldThere may be a yieldcaustic action of thecaustic action of thecaustic action of the caustic action of the much less than lettinmuch less than lettinuncontrolleduncontrolleduncontrolleduncontrolled

marymary

dge with acid fertilizer dge with acid fertilizer nity to make Outlook nity to make Outlook yy

emerged by the 2emerged by the 2ndnd

d d reduction from the reduction from the fertilizer but it isfertilizer but it isfertilizer but it is fertilizer but it is

ng ng the nutsedge go the nutsedge go

SummSumm

•• Both Outlook and DuBoth Outlook and Duable to help to safegable to help to safegp gp gonions at sites with sonions at sites with snutsedge pressurenutsedge pressureg pg p

marymary

ual Magnum will be ual Magnum will be uard the yield of uard the yield of yysignificant yellow significant yellow

AcknowleAcknowle

•• Bob Martin, Rio FarmBob Martin, Rio Farm•• James Guidici ChrisJames Guidici ChrisJames Guidici, ChrisJames Guidici, Chris•• Don Burgeson, ConADon Burgeson, ConA

Mi i Sil R i RMi i Sil R i R•• Miriam Silva Ruiz, ReMiriam Silva Ruiz, Re

dgementsdgements

msmsstensen & Gianninistensen & Gianninistensen & Gianninistensen & GianniniAgra FoodsAgra Foods

h A i t th A i t tesearch Assistantesearch Assistant