Vol. 54â2000 - NorthEastern Weed Science Society

More documents

Recommendations

Info

EFFECT OF CORN WEED MANAGEMENT PROGRAMS ON HORSENETTLE CONTROL C. Whaley, M. J. VanGessel, and Q. Johnson' ABSTRACT Horsenettle(SolanumcarvlioenseL.) infestationshavebeenincreasingin themid-Atlantic regiondueto increasedno-tillageproductionandlackof effectivecontrolmeasuresin many crops. Horsenettleis a perennialspeciesthatemergeslatein the springandis verysensitiveto frost. Thus, fall glyphosate applications are often applied too late to be effective. Field studies wereconductedfrom1997to 1999atthreelocationsin Delaware. Thebenefitsof a fall glyphosateapplicationfollowedbyin-cropherbicideprogramson horsenettleshootpopulations were evaluatedin a no-tillagesoybean(GlycineID.iiIrX. L.) -com ~~ L.) rotationalsystem. The studies were a two-factor factorial, arranged as a randomizedcomplete block design with fourreplications.Thefirst factorwasa fallherbicideapplication.Falltreatmentswere glyphosate at 2.2 kg aiIha,applied at least two weeks prior to frost, or no fall treatment. The secondfactorwas anin-cropherbicideapplicationat3 weeks afterplanting. In-croptreatments included glyphosate, prosulfuron + primisu1furon + dicamba + nonionic surfactant, halosulfinon + dicamba+ nonionicsurfactant,dicamba+ atrazine,nicosulfuron+ rimsulfuron+ atrazine+ dicamba+ cropoil concentrate,nicosulfuron+ dicamba+ cropoil concentrate.Percentcontrol and shoot populations were recorded at planting, and at II weeks after the in-crop treatment (WAf). In the 1997-98 study, fall glyphosate applications did not improve horsenettle control compared to no fall treatment when percent control was recorded II WAT. The in-erop treatmentsof prosulfuron+ primisulfuron+ dicamba+ nonionicsurfactantandnicosulfuron+ dicamba+ cropoil concentrateprovidedover800/0control. However,atthetwo locationsin the 1998-99 studies, the fall glyphosate application increased the efficacy of most in-erop herbicide applications by reducing the number, vigor, and biomass of horsenettle shoots. At II WAT, incropapplicationsof glyphosateorprosulfuron+ primisulfuron+ dicamba+ nonionicsurfactant with no fall glyphosate applications, resulted in similar horsenettle control (>75%) to fall glyphosate applications followed by the remaining herbicide treatments. 'Grad. Res. Asst., Assist. Prof. and Ext. Assoc.,University of Delaware, Research and Education Center, Georgetown, DE 19947. 38
ROUNDUPVS. LIBERTY:WHATHAVE WE LEARNED? D.O. Lingenfelter, W.S. Curran, and E.L. Werner' ABSTRACT Experiments were conducted at Penn State University starting in 1995 with glyphosate and glufosinate resistant crops. Soybean and com studies examined these herbicides alone. in combinationwith other herbicides, postemergencefollowing soil-applied herbicides, and in sequentialpostemergenceapplications. Soybeantrialswere conductedin seven to 15 inch rows and in 3Q-inch row spacings. All com trials were conducted with 30 inch spaced rows. Glyphosate was applied at 0.75 to 1.0 lb aiJA. Glufosinate was applied at 0.27 to 0.36 lb aiJA. Post applications were applied between 3 and 6 weeks after planting. All studies were planted in redueed tillage systems that generally included spring chisel plowing and disking once or twice. Most experiments were consisted of 10 by 25 foot plots replicated threetimes. Commonweeds throughoutthese studiesincludedcommon lambsquarters(Chenopodium album L.), giant foxtail (Setaria faberi Herrm), smooth pigweed (Amaranthus Irybridus L.), velvetleaf (Abutilon theophrasti Medic), common ragweed (Ambrosia artemisiifolia L.), and yellow nutsedge (Cyperus esculentus L.). In addition, eastern black nightsbade (Solanum ptycanthum Dun.) and burcucwnber(Sicyos angula/us L.) were present in a few experiments. For Roundup Ready soybeans, row spacing did not greatly influence glyphosate performance. Glyphosatealone consistentlycontrolledmost weeds in soybean. Tank-mixturesor sequential treatmentswere generallynot neededunless weed infestationswere severe or underconditions thatpreventedsoybean canopy closure. In RoundupReady com, single glyphosatetreatments did not consistently control all weeds. Sequentialtreatmentsprovided the most consistent control whether it was a soil applied product followed by glyphosate post or two applications of glypbosate. Tank mixtures with glyphosate were slightly better than glyphosate alone, but not as consistentas sequentialtreatments. LibertyLink com results were similarto RoundupReady com results. Glufosinate alone was rarely effective for complete weed control. Sequential treatmentsthat followed a soil applied treatmentprovided the most consistent control with glufosinate. Tankmixturesandsplitpost applicationswere betterthanglufosinatealone, butnot as effective as a sequential soil applied treatment followed by glufosinate post. These resultsdemonstratethatglyphosateperformancein RoundupReadycom is different from Roundup Ready soybean, where single applications of glyphosate have been very consistent and effective. Com more often requirestwo separateapplications. Glufosinate performance in Liberty Link com is sintilar to glyphosate performance in Roundup Ready corn, butprobablyeven less likely to succeedin a single applicationapproach. Sequentialtreatments that include a soil residualherbicideapplicationfollowed by a post applicationof glufosinate havebeenmost successfulin LibertyLinkcom. 1 Asst. Ext. Agron.,Assoc. Prof.,andRes. Technol., Dept.of Agron.,PennStateUniv., University Park, PA 16802. 39
Page 1 and 2: WEED REMOVAL TIMING WITH ROUNDUP RE
Page 3 and 4: EFFECT OF HERBICIDE RATES AND IRRIG
Page 5 and 6: 40 Effect of Pronone Applied with A
Page 7 and 8: Comparisonof Sulfosateand Glyphosat
Page 9 and 10: N 1175 feet Roundup Ready Studies R
Page 11 and 12: VIRGINIA TECH'S ONLINE WEED IDENTIF
Page 13 and 14: WEED CONTROL AND YIELD OF CUT FLOWE
Page 15 and 16: Table I. Effect of napropamide and
Page 17 and 18: The Effect of Total Postemergence H
Page 19 and 20: with commercial fertilizer. In gene
Page 21 and 22: HERBICIDE APPLICATIONS VERSUS HANDW
Page 23 and 24: exceeded 4. The success of training
Page 25 and 26: _u ____ Table2: Estimatesof herbace
Page 27 and 28: DOUBLE CROP CORN WEED CONTROL IN VI
Page 29 and 30: ANNUAL WEED AND GRASS CONTROL IN CO
Page 31 and 32: MANAGING QUACKGRASSINFESTATIONSAS C
Page 33 and 34: USING HERBICIDE RESISTANT HYBRIDS T
Page 35 and 36: NICOSULFURONIRIMSULFURON COMBINATIO
Page 37: GLYPHOSATE ALONE AND PRECEDED BY PR
Page 41 and 42: In summary, application timing for
Page 43 and 44: INFLUENCE OF TIMING ON WEED MANAGEM
Page 45 and 46: IMPACT OF GLYPHOSATE TIMING AND COR
Page 47 and 48: PREEMERGENCE HERBICIDES INFLUENCE W
Page 49 and 50: COMPARISON OF WEED CONTROL SYSTEMS
Page 51 and 52: Table I Mean Percent Weed Control V
Page 53 and 54: SMALL GRAIN WEED CONTROL - NEW WEED
Page 55 and 56: MODE OF ACTION, ABSORPTION, TRANSLO
Page 57 and 58: INFLUENCE OF CROWNVETCH WITH AND WI
Page 59 and 60: lRUMPETCREEPER, HONEYVINEMILKWEED,A
Page 61 and 62: FLUFENACET PLUS METRIBUZIN PLUS ATR
Page 63 and 64: CONTROLLING ASTERACEAE WEEDS WITH R
Page 65 and 66: 0... Figure1. GerminationRateof Roo
Page 67 and 68: BIOLOGICALLY BASED WEED CONTROL STR
Page 69 and 70: NON·NATIVE VASCULAR FLORA OF BISCA
Page 71 and 72: principally in ruderal sites. lawns
Page 73 and 74: EVALUATION OF AZAFENlDIN FOR PREEME
Page 75 and 76: AUTOMATING MONITORING OF ROADSIDE W
Page 77 and 78: Table I: Swnmary of brush managemen
Page 79 and 80: Table I: Sequence codes and general
Page 81 and 82: IR-4 ORNAMENTAL RESEARCH PROGRESS F
Page 83 and 84: personnel with many of the illegal
Page 85 and 86: TOLERANCE OF ORNAMENTAL GROUNDCOVER
Page 87 and 88: MUGWORT CONTROL WITH CLOPYRALID AND
Page 89 and 90:
POTENTIAL WEEDINESS OF SEVERAL NEW
Page 91 and 92:
Table I: Identification, morphologi
Page 93 and 94:
Trifolium tricolor 232 26 62 0 18 S
Page 95 and 96:
NUTRIENT REMOVAL BY WEEDS IN CONTAI
Page 97 and 98:
CONTROL OF POAANNUA FROM MULTIPLE S
Page 99 and 100:
ANNUAL BLUEGRASS (PDaannual CONTROL
Page 101 and 102:
LATERAL DEVELOPMENT OF PLANT oaowra
Page 103 and 104:
RE-ROOTING OF FOUR VARIETIES OF CRE
Page 105 and 106:
Table 2. Top growth weights (fresh)
Page 107 and 108:
CONTROL OF DALLISGRASS IN COOL SEAS
Page 109 and 110:
Kentucky bluegrass was rated to hav
Page 111 and 112:
Table 2. Fresh weight (grams) barve
Page 113 and 114:
MANAGING FENOXAPROP RESIST ANT CRAB
Page 115 and 116:
ADVANCED FORMULATION TECHNOLOGY FOR
Page 117 and 118:
Table I. Preemergence smooth crabgr
Page 119 and 120:
0.57EW at O.l21bs ai/A plus Confron
Page 121 and 122:
EFFICACY OF DITHIOPYR FORMULATIONS
Page 123 and 124:
EFFECTS OF DROUGHT ON THE INTERFERE
Page 125 and 126:
WEED MANAGEMENT WITH HALOSULFURON I
Page 127 and 128:
WEED CONTROL IN SWEET CORN WITH CAR
Page 129 and 130:
COMPARISON OF USING LEAF AREA AND W
Page 131 and 132:
RESULTS OF NEW YORK VINEYARD TRIALS
Page 133 and 134:
HERBICIDE TOLERANCE IN CRANBERRIES
Page 135 and 136:
Classification based on action on a
Page 137 and 138:
EFFECTS OF SEVERAL POTENTIALLY USEF
Page 139 and 140:
Supplement of the 53 rd Annual Meet
Page 141 and 142:
with society activities to anyone.
Page 143 and 144:
WINTER SQUASH CULTIVARS DIFFER IN R
Page 145 and 146:
INCORPORATING QUINCLORAC IN AUTUMN
Page 147 and 148:
Control efforts aim to eradicate bo
Page 149 and 150:
Table I Weed canopy, insect and dis
Page 151 and 152:
Table 1: Percent mortality of respr
show all

Vol. 54â2000 - NorthEastern Weed Science Society

Create successful ePaper yourself

Delete template?

Save as template?

Vol. 54â2000 - NorthEastern Weed Science Society