INTERNATIONAL HERBICIDE-RESISTANT WEED DATABASE
Most Recent Cases of Herbicide Resistant Weeds Entered into the Database
(click on a column header to sort or click on a country for details)
#Date Last UpdatedSpeciesCountryFirst YearSite of Action
1 November 9, 2023Amaranthus palmeriUnited States (Idaho) United StatesIdaho202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth27265
2 November 9, 2023Amaranthus tuberculatus (=A. rudis)United States (Idaho) United StatesIdaho202345 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		219Tall Waterhemp27264
3 October 30, 2023Amaranthus tuberculatus (=A. rudis)United States (Iowa) United StatesIowa202145 Auxin Mimics HRAC Group 4 (Legacy O)
 		219Tall Waterhemp27263
4 October 18, 2023Poa annuaIrelandIreland 202181 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		130Annual Bluegrass27262
5 September 14, 2023Ambrosia artemisiifoliaUkraineUkraine 2023230 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		18Common Ragweed26266
6 September 5, 2023Echinochloa crus-galli var. crus-galliBrazilBrazil 20185 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Cellulose Synthesis HRAC Group 29 (Legacy L)
Auxin Mimics HRAC Group 4 (Legacy O)
 		79Barnyardgrass26265
7 September 5, 2023Bidens subalternansBrazilBrazil 20235 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		194Greater Beggarticks26263
8 September 5, 2023Sagittaria montevidensisBrazilBrazil 20235 Auxin Mimics HRAC Group 4 (Legacy O)
 		146California Arrowhead26264
9 August 28, 2023Bromus diandrusAustralia (Western Australia) AustraliaWestern Australia20201 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		197Ripgut Brome26262
10 July 13, 2023Echinochloa crus-galli var. crus-galliIndiaIndia 201721 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		79Barnyardgrass25264
11 July 11, 2023Amaranthus palmeriUnited States (Colorado) United StatesColorado202145 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth25265
12 July 11, 2023Amaranthus powelliiCanada (Ontario) CanadaOntario20197 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Auxin Mimics HRAC Group 4 (Legacy O)
 		15Powell Amaranth24243
13 July 6, 2023Digitaria sanguinalisNew ZealandNew Zealand 202230 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		77Large Crabgrass25262
14 June 29, 2023Hordeum jubatumCanada (Alberta) CanadaAlberta20227 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		358Foxtail Barley25263
15 May 9, 2023Echinochloa oryzoidesArgentinaArgentina 201648 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		261Early Watergrass25261
16 May 9, 2023Poa annuaUnited States (Georgia) United StatesGeorgia202245 Inhibition of Cellulose Synthesis HRAC Group 29 (Legacy L)
 		130Annual Bluegrass25260
17 April 25, 2023Kochia scopariaCanada (Saskatchewan) CanadaSaskatchewan20217 Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		101Kochia25259
18 April 24, 2023Bromus commutatusUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		357Meadow Brome25258
19 April 23, 2023Bromus sterilisUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		289Poverty Brome25257
20 April 23, 2023Bromus diandrusUnited KingdomUnited Kingdom 202044 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		197Ripgut Brome25256
21 March 28, 2023Amaranthus palmeriUnited States (Kansas) United StatesKansas202145 Multiple Resistance: 6 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
PSII inhibitors - Histidine 215 Binders HRAC Group 6 (Legacy C3)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth24257
22 March 15, 2023Amaranthus retroflexusUnited States (North Carolina) United StatesNorth Carolina202245 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
 		16Redroot Pigweed24259
23 March 15, 2023Amaranthus retroflexusUnited States (North Carolina) United StatesNorth Carolina202245 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		16Redroot Pigweed24258
24 March 15, 2023Amaranthus retroflexusUnited States (North Carolina) United StatesNorth Carolina202045 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		16Redroot Pigweed22235
25 March 8, 2023Cyperus esculentusItalyItaly 201724 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		290Yellow Nutsedge24256
26 February 16, 2023Stellaria mediaUnited States (California) United StatesCalifornia202245 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		168Common Chickweed24253
27 January 31, 2023Amaranthus palmeriUruguayUruguay 202273 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth24254
28 January 31, 2023Amaranthus hybridus (syn: quitensis)UruguayUruguay 202273 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Smooth Pigweed24255
29 December 20, 2022Lolium perenne ssp. multiflorumUnited States (North Carolina) United StatesNorth Carolina202245 Multiple Resistance: 4 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PS I Electron Diversion HRAC Group 22 (Legacy D)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		110Italian Ryegrass24251
30 December 4, 2022Amaranthus hybridus (syn: quitensis)ParaguayParaguay 202246 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		12Smooth Pigweed24252
31 November 22, 2022Chenopodium albumUkraineUkraine 2022230 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		47Common Lambsquarters24250
32 November 3, 2022Alopecurus myosuroidesSwitzerlandSwitzerland 201941 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		6Blackgrass20228
33 November 3, 2022Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 202041 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		110Italian Ryegrass24249
34 November 3, 2022Conyza canadensisSwitzerlandSwitzerland 202141 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		61Horseweed24248
35 November 3, 2022Conyza bonariensisSwitzerlandSwitzerland 202041 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		60Hairy Fleabane24247
36 October 24, 2022Panicum dichotomiflorumUnited States (Illinois) United StatesIllinois201945 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		122Fall Panicum24246
37 October 24, 2022Amaranthus tuberculatus (=A. rudis)UruguayUruguay 202273 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		219Tall Waterhemp24245
38 October 24, 2022Amaranthus palmeriUnited States (North Carolina) United StatesNorth Carolina202245 Inhibition of Glutamine Synthetase HRAC Group 10 (Legacy H)
 		14Palmer Amaranth24244
39 October 6, 2022Amaranthus tuberculatus (=A. rudis)Canada (Ontario) CanadaOntario20217 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		219Tall Waterhemp24242
40 July 26, 2022Amaranthus palmeriSouth AfricaSouth Africa 201837 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth23244
41 July 11, 2022Amaranthus hybridus (syn: quitensis)ArgentinaArgentina 202148 Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
 		12Smooth Pigweed23243
42 July 6, 2022Echinochloa crus-galli var. crus-galliViet NamViet Nam 201774 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Cellulose Synthesis HRAC Group 29 (Legacy L)
 		79Barnyardgrass23242
43 June 13, 2022Amaranthus palmeriUnited States (North Carolina) United StatesNorth Carolina202245 PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		14Palmer Amaranth23241
44 June 12, 2022Anthriscus caucalisGermanyGermany 201718 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		356Bur Chervil23240
45 April 27, 2022Digitaria sanguinalisArgentinaArgentina 201948 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		77Large Crabgrass23239
46 April 8, 2022Raphanus raphanistrumAustralia (Western Australia) AustraliaWestern Australia20201 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
Auxin Mimics HRAC Group 4 (Legacy O)
 		141Wild Radish19219
47 March 18, 2022Sorghum halepenseUnited States (Missouri) United StatesMissouri201945 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		166Johnsongrass23238
48 March 14, 2022Cyperus difformisIndiaIndia 201721 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		71Smallflower Umbrella Sedge23236
49 March 11, 2022Poa annuaUnited States (Tennessee) United StatesTennessee201745 Multiple Resistance: 7 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
Inhibition of Glutamine Synthetase HRAC Group 10 (Legacy H)
Inhibition of Microtubule AssemblyHRAC Group 3 (Legacy K1)
Inhibition of Cellulose Synthesis HRAC Group 29 (Legacy L)
 		130Annual Bluegrass23237
50 February 8, 2022Lolium perenne ssp. multiflorumCanada (Ontario) CanadaOntario20217 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		110Italian Ryegrass22236
51 December 14, 2021Lolium perenne ssp. multiflorumIrelandIreland 202181 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		110Italian Ryegrass21237
52 December 14, 2021Alopecurus myosuroidesIrelandIreland 202181 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		6Blackgrass21236
53 November 23, 2021Tripleurospermum perforatum (=T. inodorum)Czech RepublicCzech Republic 202112 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		116Scentless Chamomile21235
54 October 25, 2021Bromus tectorumCanada (Alberta) CanadaAlberta20217 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		40Downy Brome (Cheatgrass)21234
55 October 8, 2021Zea mays ssp. mexicanaFranceFrance 202017 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		354Mexican teosinte21231
56 October 8, 2021Ambrosia artemisiifoliaFranceFrance 201317 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		18Common Ragweed21230
57 September 27, 2021Aster squamatusMexicoMexico 202129 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		353Saltmarsh Aster21229
58 September 9, 2021Arabidopsis thalianaUnited States (Virginia) United StatesVirginia201545 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		292Mouse-ear Cress21232
59 August 30, 2021Amaranthus retroflexusUkraineUkraine 2020230 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		16Redroot Pigweed20231
60 August 30, 2021Polygonum pensylvanicumUnited States (Arkansas) United StatesArkansas202045 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		135Pennsylvania Smartweed20230
61 August 30, 2021Amaranthus palmeriUnited States (Arkansas) United StatesArkansas202045 Inhibition of Glutamine Synthetase HRAC Group 10 (Legacy H)
 		14Palmer Amaranth20229
62 August 16, 2021Digitaria insularisParaguayParaguay 202046 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		239Sourgrass20223
63 August 11, 2021Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 201841 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		110Italian Ryegrass20226
64 August 11, 2021Lolium perenne ssp. multiflorumSwitzerlandSwitzerland 201841 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
 		110Italian Ryegrass20227
65 August 11, 2021Sorghum halepenseSerbiaSerbia 2018245 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		166Johnsongrass20225
66 August 11, 2021Ambrosia artemisiifoliaSerbiaSerbia 2019245 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		18Common Ragweed20224
67 July 11, 2021Leptochloa fusca spp. fasicularisUnited States (California) United StatesCalifornia202045 Inhibition of Deoxy-D-Xylulose Phosphate SynthaseHRAC Group 13 (Legacy F4)
 		355Bearded Sprangletop21233
68 May 5, 2021Chloris radiataColombiaColombia 201910 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		340Radiate Fingergrass19224
69 May 3, 2021Raphanus raphanistrumAustralia (Western Australia) AustraliaWestern Australia20151 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Phytoene Desaturase inhibitorsHRAC Group 12 (Legacy F1)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
Auxin Mimics HRAC Group 4 (Legacy O)
 		141Wild Radish19223
70 April 29, 2021Amaranthus tuberculatus (=A. rudis)United States (North Carolina) United StatesNorth Carolina202045 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
PSII inhibitors - Serine 264 Binders HRAC Group 5 (Legacy C1 C2)
Inhibition of Protoporphyrinogen Oxidase HRAC Group 14 (Legacy E)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase HRAC Group 27 (Legacy F2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		219Tall Waterhemp19222
71 March 13, 2021Amaranthus palmeriUnited States (Tennessee) United StatesTennessee202045 Multiple Resistance: 2 Sites of Action
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
Auxin Mimics HRAC Group 4 (Legacy O)
 		14Palmer Amaranth19221
72 March 10, 2021Salsola tragusArgentinaArgentina 201948 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		147Russian-thistle19218
73 March 9, 2021Oryza sativa var. sylvaticaTurkeyTurkey 202071 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		242Red Rice19217
74 February 26, 2021Arctotheca calendulaAustralia (Western Australia) AustraliaWestern Australia20201 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Phytoene Desaturase inhibitorsHRAC Group 12 (Legacy F1)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		21Capeweed19216
75 February 23, 2021Rapistrum rugosumAustralia (New South Wales ) AustraliaNew South Wales 20211 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		142Turnipweed19215
76 February 23, 2021Echinochloa crus-galli var. crus-galliAustralia (New South Wales ) AustraliaNew South Wales 20211 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		79Barnyardgrass19214
77 February 4, 2021Euphorbia heterophyllaBrazilBrazil 20195 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		87Wild Poinsettia19213
78 February 4, 2021Digitaria insularisBrazilBrazil 20205 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		239Sourgrass19212
79 February 1, 2021Echinochloa crus-galli var. crus-galliBrazilBrazil 20205 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		79Barnyardgrass19211
80 January 25, 2021Bromus sterilisCzech RepublicCzech Republic 201712 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		289Poverty Brome18211
81 December 16, 2020Bromus rubensSpainSpain 201838 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		324Red Brome18210
82 November 26, 2020Bromus madritensisSpainSpain 201838 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		352Compact Brome18209
83 November 13, 2020Eleusine indicaItalyItaly 201924 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		81Goosegrass18208
84 October 20, 2020Amaranthus tuberculatus (=A. rudis)IsraelIsrael 201923 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		219Tall Waterhemp18207
85 October 7, 2020Amaranthus palmeriUnited States (Connecticut) United StatesConnecticut201945 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth18206
86 October 7, 2020Xanthium strumariumKazakhstanKazakhstan 2015157 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		174Common cocklebur18205
87 October 1, 2020Apera spica-ventiBelgiumBelgium 20193 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		20Silky Windgrass18199
88 September 23, 2020Amaranthus palmeriSpainSpain 201638 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		14Palmer Amaranth18204
89 September 21, 2020Poa annuaNew ZealandNew Zealand 202030 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		130Annual Bluegrass18203
90 September 21, 2020Lolium perenne ssp. multiflorumNew ZealandNew Zealand 201430 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		110Italian Ryegrass18202
91 September 21, 2020Lolium perenneNew ZealandNew Zealand 201430 Inhibition of Acetolactate Synthase HRAC Group 2 (Legacy B)
 		111Perennial Ryegrass18201
92 September 10, 2020Avena fatuaIrelandIreland 201981 Inhibition of Acetyl CoA Carboxylase HRAC Group 1 (Legacy A)
 		28Wild Oat18200
93 July 3, 2020Conyza canadensisFranceFrance 201917 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		61Horseweed18198
94 June 22, 2020Eleusine indicaMexicoMexico 201629 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		81Goosegrass18194
95 June 22, 2020Chloris barbata = (C. inflate)MexicoMexico 201829 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		53Swollen Fingergrass18197
96 June 22, 2020Parthenium hysterophorusMexicoMexico 201729 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		124Ragweed Parthenium18196
97 June 22, 2020Amaranthus palmeriMexicoMexico 201629 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		14Palmer Amaranth18195
98 June 22, 2020Sorghum halepenseAustralia (Queensland) AustraliaQueensland20191 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		166Johnsongrass18193
99 June 22, 2020Hordeum murinum ssp. leporinumSpainSpain 201838 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase HRAC Group 9 (Legacy G)
 		98Hare Barley18192
100 May 20, 2020Eleusine indicaUnited States (Alabama) United StatesAlabama201945 PS I Electron Diversion HRAC Group 22 (Legacy D)
 		81Goosegrass18191
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