A. W. Ezell, J. L. Yeiser, and L. R. Nelson

HERBACEOUS WEEED CONTROL IN HERBACEOUS WEEED CONTROL IN FIRST – YEAR LOBLOLLY PINE FIRST – YEAR LOBLOLLY PINE

PLANTATIONS USING OUST XP, PLANTATIONS USING OUST XP, OUST EXTRA, OUSTAR, MATRIX, OUST EXTRA, OUSTAR, MATRIX,

AND STEADFASTAND STEADFAST

A. W. Ezell, J. L. Yeiser, and L. R. NelsonA. W. Ezell, J. L. Yeiser, and L. R. Nelson

AcknowledgementsAcknowledgements

• Dupont Chemical CompanyDupont Chemical Company

• Plum Creek Timber CompanyPlum Creek Timber Company

• Boise-CascadeBoise-Cascade

BackgroundBackground

• Herbaceous weed control is an Herbaceous weed control is an essential component of loblolly pine essential component of loblolly pine plantation establishmentplantation establishment

• Evaluation on new or currently labeled Evaluation on new or currently labeled products may produce new options for products may produce new options for land managersland managers

MATERIALS AND METHODSMATERIALS AND METHODS

• STUDY SITESSTUDY SITES– MISSISSIPPIMISSISSIPPI

• Plum Creek Timber Co. landPlum Creek Timber Co. land• Previous Cover = mixed pine-hardwood natural Previous Cover = mixed pine-hardwood natural

standstand• Harvested – 2002Harvested – 2002• Chemical site preparation – 2003Chemical site preparation – 2003• Subsoiled – 2003Subsoiled – 2003• Hand planted with 1-0 loblolly – January 2004Hand planted with 1-0 loblolly – January 2004• Soils = sandy clay loam, pH = 5.3Soils = sandy clay loam, pH = 5.3

• TexasTexas– Boise-Cascade landBoise-Cascade land– Harvested – Oct, 2002Harvested – Oct, 2002– Shear – July, 2003Shear – July, 2003– Burn – August, 2003Burn – August, 2003– Machine planted with 1-0 loblolly – Machine planted with 1-0 loblolly –

January, 2004January, 2004– Soil = Eastwood fine sandy loamSoil = Eastwood fine sandy loam

• South CarolinaSouth Carolina– Nonindustrial private landNonindustrial private land– Retired agricultural fieldRetired agricultural field– Disced – Summer 2003Disced – Summer 2003– Machine planted with 1-0 loblolly – January, 2004Machine planted with 1-0 loblolly – January, 2004– Soil = clay loamSoil = clay loam

List of treatments in 2004 DuPont herbaceous weed List of treatments in 2004 DuPont herbaceous weed control projectcontrol project

Treatment No.Treatment No.11 Herbicide and Rate/A (oz)Herbicide and Rate/A (oz)11 Matrix (2)Matrix (2)22 Matrix (4)Matrix (4)33 Steadfast (1)Steadfast (1)44 Steadfast (2)Steadfast (2)55 Oust Extra (2)Oust Extra (2)66 Oust Extra (3)Oust Extra (3)77 Matrix (2) + Oust Extra (2)Matrix (2) + Oust Extra (2)88 Steadfast (1) + Oust Extra (2)Steadfast (1) + Oust Extra (2)99 Oust Extra (3) + Arsenal AC (4)Oust Extra (3) + Arsenal AC (4)

1010 Oust Extra (2) + Arsenal AC (4)Oust Extra (2) + Arsenal AC (4)1111 Matrix (2) + Arsenal AC (4)Matrix (2) + Arsenal AC (4)1212 Steadfast (1) + Arsenal AC (4)Steadfast (1) + Arsenal AC (4)1313 Arsenal AC (4)Arsenal AC (4)1414 Oust XP (2) + Arsenal AC (4)Oust XP (2) + Arsenal AC (4)1515 Oustar (13)Oustar (13)1616 UntreatedUntreated

11Treatments 1,2,3,4,7, and 8 had Timbersurf 90 added (12.8 oz/A)Treatments 1,2,3,4,7, and 8 had Timbersurf 90 added (12.8 oz/A)

• ApplicationApplication– COCO22 –powered backpack sprayer –powered backpack sprayer

– 4-nozzle boom with 8001 tips4-nozzle boom with 8001 tips– 10 gpa10 gpa– 5-foot bands centered over planted row5-foot bands centered over planted row– Dates of applicationDates of application

• MS - April 13, 2004MS - April 13, 2004• TX - April 5, 2004TX - April 5, 2004• SC – April 14, 2004SC – April 14, 2004

Experimental DesignExperimental Design

– MS = RCB with 4 replicationsMS = RCB with 4 replications– SC = RCB with 4 replicationsSC = RCB with 4 replications– TX = RCB with 4 replicationsTX = RCB with 4 replications

EvaluationEvaluation

• Ocular evaluation of percent ground Ocular evaluation of percent ground coverage at 30, 60, 90, and 120 DATcoverage at 30, 60, 90, and 120 DAT

• Tree vigor at 30-day intervalsTree vigor at 30-day intervals

• Initial height and groundline diameter Initial height and groundline diameter (GLD)(GLD)

• Height and GLD - 1GSATHeight and GLD - 1GSAT

AnalysisAnalysis

• ANOVAANOVA

• DNMRTDNMRT

RESULTSRESULTS

Major Herbaceous SpeciesMajor Herbaceous Species

MSMSBull paspalum*, panic grasses, Andropogon, late boneset, Bull paspalum*, panic grasses, Andropogon, late boneset, goldenrod, fireweed, common ragweed, dogfennelgoldenrod, fireweed, common ragweed, dogfennel

TXTXpanic grasses, Chasmanthium, Paspalum, Andropogon, late panic grasses, Chasmanthium, Paspalum, Andropogon, late boneset, common ragweed, dogfennel, purple cudweedboneset, common ragweed, dogfennel, purple cudweed

SCSCperennial ryegrass, wild radish, Johnsongrass, common perennial ryegrass, wild radish, Johnsongrass, common ragweed, panic grassesragweed, panic grasses

30 DAT

30 DAT

60 DAT

30 DAT

60 DAT

60 DAT

90 DAT

120 DAT

120 DAT

SummarySummary

• No treatments resulted in negative impact on loblolly No treatments resulted in negative impact on loblolly seedlingsseedlings

• Only treatments to provide “best” control in all three Only treatments to provide “best” control in all three states were Oust Extra + Arsenal AC combinationsstates were Oust Extra + Arsenal AC combinations

• Oustar and Oust XP + Arsenal AC treatments Oustar and Oust XP + Arsenal AC treatments provided “best” control at two of three locationsprovided “best” control at two of three locations

• Matrix and Steadfast did not provide acceptable Matrix and Steadfast did not provide acceptable control on these sitescontrol on these sites

• Good to be able to test new products and/or Good to be able to test new products and/or applications, but sometimes, the answer is “no”applications, but sometimes, the answer is “no”

• Oust Extra + Arsenal AC combinations provided Oust Extra + Arsenal AC combinations provided excellent results on a wide variety of speciesexcellent results on a wide variety of species