1
| 307 | Wild Carrot | 1957 | Daucus carota Wild Carrot | Canada (Ontario) | Ontario | Ontario | Synthetic Auxins (O/4) |
Synthetic Auxins (O/4)
| 2,4-D | Clarence Swanton, Chris Hall |
2
| 58 | Common Lambsquarters | 1973 | Chenopodium album Common Lambsquarters | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
3
| 59 | Common Ragweed | 1976 | Ambrosia artemisiifolia Common Ragweed | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
4
| 60 | Lateflowering Goosefoot | 1976 | Chenopodium album var. striatum (=C. strictum var. glaucophyllum) Lateflowering Goosefoot | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
5
| 1158 | Powell Amaranth | 1977 | Amaranthus powellii Powell Amaranth | Canada (Ontario) | Ontario | | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine, metribuzin | Francois Tardif, Clarence Swanton |
6
| 5066 | Common Groundsel | 1977 | Senecio vulgaris Common Groundsel | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Hugh Beckie |
7
| 61 | Redroot Pigweed | 1980 | Amaranthus retroflexus Redroot Pigweed | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
8
| 62 | Barnyardgrass | 1981 | Echinochloa crus-galli var. crus-galli Barnyardgrass | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
9
| 63 | Witchgrass | 1981 | Panicum capillare Witchgrass | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
10
| 64 | Yellow Foxtail | 1981 | Setaria pumila (=S. glauca) Yellow Foxtail | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Clarence Swanton |
11
| 5065 | Wild Mustard | 1983 | Sinapis arvensis Wild Mustard | Canada (Ontario) | Ontario | Ontario | Photosystem II inhibitors (C1/5) |
Photosystem II inhibitors (C1/5)
| atrazine | Hugh Beckie |
12
| 48 | Horseweed | 1993 | Conyza canadensis Horseweed | Canada (Ontario) | Ontario | Ontario | PSI Electron Diverter (D/22) |
PSI Electron Diverter (D/22)
| paraquat | Susan Weaver |
13
| 49 | Virginia Pepperweed | 1993 | Lepidium virginicum Virginia Pepperweed | Canada (Ontario) | Ontario | Ontario | PSI Electron Diverter (D/22) |
PSI Electron Diverter (D/22)
| paraquat | Susan Weaver |
14
| 5049 | Powell Amaranth | 1998 | Amaranthus powellii Powell Amaranth | Canada (Ontario) | Ontario | Ontario | ALS inhibitors (B/2), Photosystem II inhibitors (C1/5) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) Photosystem II inhibitors (C1/5)
| atrazine, imazethapyr, metribuzin | Francois Tardif |
15
| 1159 | Powell Amaranth | 1998 | Amaranthus powellii Powell Amaranth | Canada (Ontario) | Ontario | Ontario | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| imazethapyr, thifensulfuron-methyl | Francois Tardif |
16
| 1161 | Redroot Pigweed | 1998 | Amaranthus retroflexus Redroot Pigweed | Canada (Ontario) | Ontario | Ontario | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| imazethapyr, thifensulfuron-methyl | Francois Tardif |
17
| 5048 | Powell Amaranth | 1999 | Amaranthus powellii Powell Amaranth | Canada (Ontario) | Ontario | | Photosystem II inhibitors (C1/5), PSII inhibitor (Ureas and amides) (C2/7) |
Multiple Resistance: 2 Sites of Action Photosystem II inhibitors (C1/5) PSII inhibitor (Ureas and amides) (C2/7)
| atrazine, linuron, monolinuron, prometryn | Francois Tardif |
18
| 5471 | Common Ragweed | 2000 | Ambrosia artemisiifolia Common Ragweed | Canada (Ontario) | Ontario | | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| chlorimuron-ethyl, cloransulam-methyl, imazethapyr | Francois Tardif |
19
| 5211 | Eastern Black Nightshade | 2000 | Solanum ptycanthum Eastern Black Nightshade | Canada (Ontario) | Ontario | | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| flumetsulam, imazamox, imazethapyr, nicosulfuron, primisulfuron-methyl, prosulfuron, rimsulfuron | Francois Tardif, Jamshid Ashigh |
20
| 5123 | Common Lambsquarters | 2001 | Chenopodium album Common Lambsquarters | Canada (Ontario) | Ontario | Ontario | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| thifensulfuron-methyl | Francois Tardif |
21
| 5124 | Green Foxtail | 2001 | Setaria viridis Green Foxtail | Canada (Ontario) | Ontario | | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| flucarbazone-sodium, imazethapyr, nicosulfuron, pyrithiobac-sodium | Francois Tardif |
22
| 5125 | Redroot Pigweed | 2001 | Amaranthus retroflexus Redroot Pigweed | Canada (Ontario) | Ontario | | PSII inhibitor (Ureas and amides) (C2/7) |
PSII inhibitor (Ureas and amides) (C2/7)
| linuron | Francois Tardif |
23
| 5212 | Tall Waterhemp | 2002 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), Photosystem II inhibitors (C1/5) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) Photosystem II inhibitors (C1/5)
| atrazine, imazethapyr | Francois Tardif |
24
| 5213 | Tall Waterhemp | 2002 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| imazethapyr | Francois Tardif |
25
| 5210 | Giant Foxtail | 2003 | Setaria faberi Giant Foxtail | Canada (Ontario) | Ontario | | ALS inhibitors (B/2) |
ALS inhibitors (B/2)
| imazethapyr | Francois Tardif |
26
| 5472 | Smooth Pigweed | 2004 | Amaranthus hybridus (syn: quitensis) Smooth Pigweed | Canada (Ontario) | Ontario | | PSII inhibitors (Nitriles) (C3/6) |
PSII inhibitors (Nitriles) (C3/6)
| bentazon, bromoxynil | Francois Tardif |
27
| 5473 | Redroot Pigweed | 2005 | Amaranthus retroflexus Redroot Pigweed | Canada (Ontario) | Ontario | | PSII inhibitors (Nitriles) (C3/6) |
PSII inhibitors (Nitriles) (C3/6)
| bentazon, bromoxynil | Francois Tardif |
28
| 5483 | Giant Ragweed | 2008 | Ambrosia trifida Giant Ragweed | Canada (Ontario) | Ontario | | EPSP synthase inhibitors (G/9) |
EPSP synthase inhibitors (G/9)
| glyphosate | Francois Tardif |
29
| 5493 | Eastern Black Nightshade | 2009 | Solanum ptycanthum Eastern Black Nightshade | Canada (Ontario) | Ontario | | PSI Electron Diverter (D/22) |
PSI Electron Diverter (D/22)
| paraquat | Francois Tardif, Kristen Obeid |
30
| 5665 | Horseweed | 2010 | Conyza canadensis Horseweed | Canada (Ontario) | Ontario | | EPSP synthase inhibitors (G/9) |
EPSP synthase inhibitors (G/9)
| glyphosate | Francois Tardif |
31
| 5666 | Horseweed | 2011 | Conyza canadensis Horseweed | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9)
| cloransulam-methyl, glyphosate | Francois Tardif |
32
| 5678 | Large Crabgrass | 2011 | Digitaria sanguinalis Large Crabgrass | Canada (Ontario) | Ontario | | ACCase inhibitors (A/1) |
ACCase inhibitors (A/1)
| clethodim, fenoxaprop-P-ethyl, fluazifop-P-butyl, quizalofop-P-ethyl, sethoxydim | Francois Tardif, Kristen Obeid, Martin Laforest, Brahim Soufiane, Robert Nurse, Eric Page, Marie-Josée Simard |
33
| 7833 | Giant Ragweed | 2011 | Ambrosia trifida Giant Ragweed | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9)
| cloransulam-methyl, glyphosate | Francois Tardif |
34
| 5713 | Common Ragweed | 2012 | Ambrosia artemisiifolia Common Ragweed | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9)
| chlorimuron-ethyl, cloransulam-methyl, glyphosate, imazamethabenz-methyl | Francois Tardif |
35
| 9940 | Tall Waterhemp | 2014 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9) |
Multiple Resistance: 2 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9)
| glyphosate, imazethapyr | Peter Sikkema |
36
| 17140 | Tall Waterhemp | 2017 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9), Photosystem II inhibitors (C1/5), PPO inhibitors (E/14) |
Multiple Resistance: 4 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9) Photosystem II inhibitors (C1/5) PPO inhibitors (E/14)
| atrazine, glyphosate, imazethapyr, lactofen | Peter Sikkema |
37
| 17141 | Tall Waterhemp | 2017 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | ALS inhibitors (B/2), EPSP synthase inhibitors (G/9), Photosystem II inhibitors (C1/5) |
Multiple Resistance: 3 Sites of Action ALS inhibitors (B/2) EPSP synthase inhibitors (G/9) Photosystem II inhibitors (C1/5)
| atrazine, glyphosate, imazethapyr | Peter Sikkema |
38
| 17142 | Tall Waterhemp | 2017 | Amaranthus tuberculatus (=A. rudis) Tall Waterhemp | Canada (Ontario) | Ontario | | EPSP synthase inhibitors (G/9), Photosystem II inhibitors (C1/5) |
Multiple Resistance: 2 Sites of Action EPSP synthase inhibitors (G/9) Photosystem II inhibitors (C1/5)
| atrazine, glyphosate, metribuzin | Peter Sikkema |