International Survey of Herbicide-Resistant Weeds

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Herbicide Resistant Weeds in Canada
Herbicide Resistant Weeds in Canada
Herbicide Resistant Weeds in Canada
State  
Herbicide Resistant Weeds in Canada
 #SpeciesCommon NameState NameFirst YearSite of Action

State: Alberta
  1 Stellaria mediaCommon ChickweedCanadaAlberta19887 Inhibition of Acetolactate Synthase (B/2)
 		481
  2 Kochia scopariaKochiaCanadaAlberta19897 Inhibition of Acetolactate Synthase (B/2)
 		65
  3 Avena fatuaWild OatCanadaAlberta19897 Multiple Resistance: 2 Sites of Action
Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
Cell elongation inhibitors (Z/8)
 		66
  4 Setaria viridisGreen FoxtailCanadaAlberta19897 Inhibition of Microtubule Assembly (K1/3)
 		5071
  5 Avena fatuaWild OatCanadaAlberta19917 Inhibition of Acetyl CoA Carboxylase (A/1)
 		67
  6 Sinapis arvensisWild MustardCanadaAlberta19937 Inhibition of Acetolactate Synthase (B/2)
 		5036
  7 Galium spuriumFalse CleaversCanadaAlberta19967 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
 		508
  8 Sonchus asperSpiny SowthistleCanadaAlberta19967 Inhibition of Acetolactate Synthase (B/2)
 		1153
  9 Setaria viridisGreen FoxtailCanadaAlberta19967 Inhibition of Acetyl CoA Carboxylase (A/1)
 		5039
  10 Galeopsis tetrahitCommon HempnettleCanadaAlberta19987 Auxin Mimics (O/4)
 		1154
  11 Neslia paniculataBall MustardCanadaAlberta19987 Inhibition of Acetolactate Synthase (B/2)
 		1155
  12 Avena fatuaWild OatCanadaAlberta19987 Inhibition of Acetolactate Synthase (B/2)
 		5075
  13 Avena fatuaWild OatCanadaAlberta19987 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
 		5076
  14 Thlaspi arvenseField PennycressCanadaAlberta20017 Inhibition of Acetolactate Synthase (B/2)
 		5097
  15 Galeopsis tetrahitCommon HempnettleCanadaAlberta20067 Inhibition of Acetolactate Synthase (B/2)
 		5320
  16 Polygonum convolvulus (=Fallopia convolvulus)Wild BuckwheatCanadaAlberta20077 Inhibition of Acetolactate Synthase (B/2)
 		5379
  17 Salsola tragusRussian-thistleCanadaAlberta20077 Inhibition of Acetolactate Synthase (B/2)
 		7831
  18 Lolium persicumPersian DarnelCanadaAlberta20097 Inhibition of Acetyl CoA Carboxylase (A/1)
 		7832
  19 Crepis tectorumNarrowleaf HawksbeardCanadaAlberta20117 Inhibition of Acetolactate Synthase (B/2)
 		5606
  20 Capsella bursa-pastorisShepherd's-purseCanadaAlberta20117 Inhibition of Acetolactate Synthase (B/2)
 		5623
  21 Kochia scopariaKochiaCanadaAlberta20127 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		5592
  22 Vaccaria hispanicaCowcockleCanadaAlberta20127 Inhibition of Acetolactate Synthase (B/2)
 		5616
  23 Polygonum lapathifoliumPale SmartweedCanadaAlberta20147 Inhibition of Acetolactate Synthase (B/2)
 		11002
  24 Kochia scopariaKochiaCanadaAlberta20177 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
Auxin Mimics (O/4)
 		17147
  25 Bromus tectorumDowny Brome (Cheatgrass)CanadaAlberta20217 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		21234
  26 Hordeum jubatumFoxtail BarleyCanadaAlberta20227 Inhibition of Acetyl CoA Carboxylase (A/1)
 		25263

State: British Columbia
  27 Centaurea stoebe ssp. micranthosSpotted knapweedCanadaBritish Columbia20137 Auxin Mimics (O/4)
 		15061

State: Manitoba
  28 Setaria viridisGreen FoxtailCanadaManitoba19887 Inhibition of Microtubule Assembly (K1/3)
 		52
  29 Kochia scopariaKochiaCanadaManitoba19887 Inhibition of Acetolactate Synthase (B/2)
 		57
  30 Avena fatuaWild OatCanadaManitoba19907 Inhibition of Acetyl CoA Carboxylase (A/1)
 		50
  31 Sinapis arvensisWild MustardCanadaManitoba19907 Auxin Mimics (O/4)
 		55
  32 Setaria viridisGreen FoxtailCanadaManitoba19917 Inhibition of Acetyl CoA Carboxylase (A/1)
 		53
  33 Sinapis arvensisWild MustardCanadaManitoba19927 Inhibition of Acetolactate Synthase (B/2)
 		54
  34 Setaria viridisGreen FoxtailCanadaManitoba19927 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Microtubule Assembly (K1/3)
 		5037
  35 Avena fatuaWild OatCanadaManitoba19947 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
Antimicrotubule mitotic disrupter (Z/25)
 		51
  36 Sinapis arvensisWild MustardCanadaManitoba19947 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		56
  37 Galeopsis tetrahitCommon HempnettleCanadaManitoba19957 Inhibition of Acetolactate Synthase (B/2)
 		476
  38 Avena fatuaWild OatCanadaManitoba19977 Inhibition of Acetolactate Synthase (B/2)
 		5077
  39 Avena fatuaWild OatCanadaManitoba19977 Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
 		5078
  40 Avena fatuaWild OatCanadaManitoba19977 Multiple Resistance: 4 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
Antimicrotubule mitotic disrupter (Z/25)
 		5079
  41 Setaria viridisGreen FoxtailCanadaManitoba20027 Inhibition of Acetolactate Synthase (B/2)
 		5221
  42 Amaranthus retroflexusRedroot PigweedCanadaManitoba20027 Inhibition of Acetolactate Synthase (B/2)
 		5222
  43 Thlaspi arvenseField PennycressCanadaManitoba20087 Inhibition of Acetolactate Synthase (B/2)
 		5624
  44 Galium spuriumFalse CleaversCanadaManitoba20087 Inhibition of Acetolactate Synthase (B/2)
 		5629
  45 Stellaria mediaCommon ChickweedCanadaManitoba20087 Inhibition of Acetolactate Synthase (B/2)
 		5630
  46 Amaranthus powelliiPowell AmaranthCanadaManitoba20087 Inhibition of Acetolactate Synthase (B/2)
 		5631
  47 Polygonum lapathifoliumPale SmartweedCanadaManitoba20097 Inhibition of Acetolactate Synthase (B/2)
 		5625
  48 Kochia scopariaKochiaCanadaManitoba20147 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		9942
  49 Avena fatuaWild OatCanadaManitoba20157 Multiple Resistance: 4 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
 		11033

State: New Brunswick
  50 Chenopodium albumCommon LambsquartersCanadaNew Brunswick20187 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		28276

State: Nova Scotia
  51 Rumex acetosellaSheep SorrelCanadaNova Scotia20117 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		17122

State: Ontario
  52 Daucus carotaWild CarrotCanadaOntario19577 Auxin Mimics (O/4)
 		307
  53 Chenopodium albumCommon LambsquartersCanadaOntario19737 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		58
  54 Ambrosia artemisiifoliaCommon RagweedCanadaOntario19767 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		59
  55 Chenopodium album var. striatum (=C. strictum var. glaucophyllum)Lateflowering GoosefootCanadaOntario19767 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		60
  56 Amaranthus powelliiPowell AmaranthCanadaOntario19777 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		1158
  57 Senecio vulgarisCommon GroundselCanadaOntario19777 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5066
  58 Amaranthus retroflexusRedroot PigweedCanadaOntario19807 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		61
  59 Echinochloa crus-galli var. crus-galliBarnyardgrassCanadaOntario19817 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		62
  60 Panicum capillareWitchgrassCanadaOntario19817 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		63
  61 Setaria pumila (=S. glauca)Yellow FoxtailCanadaOntario19817 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		64
  62 Sinapis arvensisWild MustardCanadaOntario19837 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5065
  63 Conyza canadensisHorseweedCanadaOntario19937 PS I Electron Diversion (D/22)
 		48
  64 Lepidium virginicumVirginia PepperweedCanadaOntario19937 PS I Electron Diversion (D/22)
 		49
  65 Amaranthus powelliiPowell AmaranthCanadaOntario19987 Inhibition of Acetolactate Synthase (B/2)
 		1159
  66 Amaranthus retroflexusRedroot PigweedCanadaOntario19987 Inhibition of Acetolactate Synthase (B/2)
 		1161
  67 Amaranthus powelliiPowell AmaranthCanadaOntario19987 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5049
  68 Amaranthus powelliiPowell AmaranthCanadaOntario19997 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5048
  69 Solanum ptycanthumEastern Black NightshadeCanadaOntario20007 Inhibition of Acetolactate Synthase (B/2)
 		5211
  70 Ambrosia artemisiifoliaCommon RagweedCanadaOntario20007 Inhibition of Acetolactate Synthase (B/2)
 		5471
  71 Chenopodium albumCommon LambsquartersCanadaOntario20017 Inhibition of Acetolactate Synthase (B/2)
 		5123
  72 Setaria viridisGreen FoxtailCanadaOntario20017 Inhibition of Acetolactate Synthase (B/2)
 		5124
  73 Amaranthus retroflexusRedroot PigweedCanadaOntario20017 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5125
  74 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20027 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5212
  75 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20027 Inhibition of Acetolactate Synthase (B/2)
 		5213
  76 Setaria faberiGiant FoxtailCanadaOntario20037 Inhibition of Acetolactate Synthase (B/2)
 		5210
  77 Amaranthus hybridus (syn: quitensis)Smooth PigweedCanadaOntario20047 PSII inhibitors - Histidine 215 Binders (C3/6)
 		5472
  78 Amaranthus retroflexusRedroot PigweedCanadaOntario20057 PSII inhibitors - Histidine 215 Binders (C3/6)
 		5473
  79 Ambrosia trifidaGiant RagweedCanadaOntario20087 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		5483
  80 Solanum ptycanthumEastern Black NightshadeCanadaOntario20097 PS I Electron Diversion (D/22)
 		5493
  81 Conyza canadensisHorseweedCanadaOntario20107 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		5665
  82 Conyza canadensisHorseweedCanadaOntario20117 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		5666
  83 Digitaria sanguinalisLarge CrabgrassCanadaOntario20117 Inhibition of Acetyl CoA Carboxylase (A/1)
 		5678
  84 Ambrosia trifidaGiant RagweedCanadaOntario20117 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		7833
  85 Ambrosia artemisiifoliaCommon RagweedCanadaOntario20127 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		5713
  86 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20147 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		9940
  87 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20177 Multiple Resistance: 4 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		17140
  88 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20177 Multiple Resistance: 3 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		17141
  89 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20177 Multiple Resistance: 2 Sites of Action
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		17142
  90 Amaranthus powelliiPowell AmaranthCanadaOntario20197 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
 		24243
  91 Lolium perenne ssp. multiflorumItalian RyegrassCanadaOntario20217 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		22236
  92 Amaranthus tuberculatus (=A. rudis)Tall WaterhempCanadaOntario20217 Multiple Resistance: 5 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
PSII inhibitors - Serine 264 Binders (C1 C2/5)
Inhibition of Protoporphyrinogen Oxidase (E/14)
Inhibition of Hydroxyphenyl Pyruvate Dioxygenase (F2/27)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		24242

State: Prince Edward Island
  93 Chenopodium albumCommon LambsquartersCanadaPrince Edward Island20187 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		28273
  94 Amaranthus retroflexusRedroot PigweedCanadaPrince Edward Island20237 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		28274
  95 Ambrosia artemisiifoliaCommon RagweedCanadaPrince Edward Island20237 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		28275

State: Quebec
  96 Brassica rapa (=B. campestris)Birdsrape MustardCanadaQuebec19777 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		433
  97 Amaranthus retroflexusRedroot PigweedCanadaQuebec19807 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		17126
  98 Chenopodium albumCommon LambsquartersCanadaQuebec19807 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		17132
  99 Ambrosia artemisiifoliaCommon RagweedCanadaQuebec19997 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5064
  100 Ambrosia artemisiifoliaCommon RagweedCanadaQuebec19997 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		17128
  101 Amaranthus retroflexusRedroot PigweedCanadaQuebec20017 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		5126
  102 Ambrosia artemisiifoliaCommon RagweedCanadaQuebec20077 Inhibition of Acetolactate Synthase (B/2)
 		17127
  103 Chenopodium albumCommon LambsquartersCanadaQuebec20087 Inhibition of Acetolactate Synthase (B/2)
 		17131
  104 Amaranthus retroflexusRedroot PigweedCanadaQuebec20097 Inhibition of Acetolactate Synthase (B/2)
 		17125
  105 Amaranthus powelliiPowell AmaranthCanadaQuebec20127 PSII inhibitors - Serine 264 Binders (C1 C2/5)
 		17123
  106 Amaranthus powelliiPowell AmaranthCanadaQuebec20127 Inhibition of Acetolactate Synthase (B/2)
 		17124
  107 Avena fatuaWild OatCanadaQuebec20127 Inhibition of Acetyl CoA Carboxylase (A/1)
 		17129
  108 Brassica rapa (=B. campestris)Birdsrape MustardCanadaQuebec20177 Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		17130

State: Saskatchewan
  109 Kochia scopariaKochiaCanadaSaskatchewan19887 Inhibition of Acetolactate Synthase (B/2)
 		5069
  110 Salsola tragusRussian-thistleCanadaSaskatchewan19897 Inhibition of Acetolactate Synthase (B/2)
 		5067
  111 Avena fatuaWild OatCanadaSaskatchewan19907 Inhibition of Acetyl CoA Carboxylase (A/1)
 		5041
  112 Setaria viridisGreen FoxtailCanadaSaskatchewan19917 Inhibition of Microtubule Assembly (K1/3)
 		5040
  113 Setaria viridisGreen FoxtailCanadaSaskatchewan19967 Inhibition of Acetyl CoA Carboxylase (A/1)
 		5038
  114 Setaria viridisGreen FoxtailCanadaSaskatchewan19967 Multiple Resistance: 2 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Microtubule Assembly (K1/3)
 		5070
  115 Avena fatuaWild OatCanadaSaskatchewan19967 Inhibition of Acetolactate Synthase (B/2)
 		5072
  116 Avena fatuaWild OatCanadaSaskatchewan19967 Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
 		5073
  117 Avena fatuaWild OatCanadaSaskatchewan19967 Multiple Resistance: 3 Sites of Action
Inhibition of Acetyl CoA Carboxylase (A/1)
Inhibition of Acetolactate Synthase (B/2)
Very Long-Chain Fatty Acid Synthesis inhibitors (K3 N/15)
 		5074
  118 Sinapis arvensisWild MustardCanadaSaskatchewan20027 Inhibition of Acetolactate Synthase (B/2)
 		5243
  119 Lolium persicumPersian DarnelCanadaSaskatchewan20047 Inhibition of Acetyl CoA Carboxylase (A/1)
 		5244
  120 Stellaria mediaCommon ChickweedCanadaSaskatchewan20057 Inhibition of Acetolactate Synthase (B/2)
 		5322
  121 Galium spuriumFalse CleaversCanadaSaskatchewan20067 Inhibition of Acetolactate Synthase (B/2)
 		5321
  122 Capsella bursa-pastorisShepherd's-purseCanadaSaskatchewan20087 Inhibition of Acetolactate Synthase (B/2)
 		5381
  123 Thlaspi arvenseField PennycressCanadaSaskatchewan20097 Inhibition of Acetolactate Synthase (B/2)
 		5626
  124 Chenopodium albumCommon LambsquartersCanadaSaskatchewan20097 Inhibition of Acetolactate Synthase (B/2)
 		5627
  125 Amaranthus retroflexusRedroot PigweedCanadaSaskatchewan20107 Inhibition of Acetolactate Synthase (B/2)
 		5628
  126 Kochia scopariaKochiaCanadaSaskatchewan20127 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Inhibition of Enolpyruvyl Shikimate Phosphate Synthase (G/9)
 		7834
  127 Kochia scopariaKochiaCanadaSaskatchewan20157 Multiple Resistance: 2 Sites of Action
Inhibition of Acetolactate Synthase (B/2)
Auxin Mimics (O/4)
 		11032
  128 Kochia scopariaKochiaCanadaSaskatchewan20217 Inhibition of Protoporphyrinogen Oxidase (E/14)
 		25259
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Cite this site as: Heap, I.  The International Survey of Herbicide Resistant Weeds.  Online.  Internet.  Friday, October 31, 2025 .  Available  www.weedscience.org
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