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 September 21, 2020Poa annuaNew ZealandNew Zealand 202030 ACCase inhibitors (A/1)
 		130Annual Bluegrass18203
2 September 21, 2020Apera spica-ventiBelgiumBelgium 20193 ALS inhibitors (B/2)
 		20Silky Windgrass18199
3 September 10, 2020Avena fatuaIrelandIreland 201981 ACCase inhibitors (A/1)
 		28Wild Oat18200
4 July 3, 2020Conyza canadensisFranceFrance 201917 EPSP synthase inhibitors (G/9)
 		61Horseweed18198
5 June 22, 2020Chloris barbata = (C. inflate)MexicoMexico 201829 EPSP synthase inhibitors (G/9)
 		53Swollen Fingergrass18197
6 June 22, 2020Sorghum halepenseAustralia (Queensland) AustraliaQueensland20191 EPSP synthase inhibitors (G/9)
 		166Johnsongrass18193
7 June 22, 2020Hordeum murinum ssp. leporinumSpainSpain 201838 EPSP synthase inhibitors (G/9)
 		98Hare Barley18192
8 May 20, 2020Eleusine indicaUnited States (Alabama) United StatesAlabama201945 PSI Electron Diverter (D/22)
 		81Goosegrass18191
9 January 22, 2020Avena fatuaAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
 		28Wild Oat18187
10 November 28, 2019Amaranthus hybridus (syn: quitensis)BrazilBrazil 20185 Multiple Resistance: 2 Sites of Action
ALS inhibitors (B/2)
EPSP synthase inhibitors (G/9)
 		12Smooth Pigweed18184
11 November 28, 2019Secale cerealeUnited States (Colorado) United StatesColorado201845 ALS inhibitors (B/2)
 		351Feral Rye18182
12 November 28, 2019Echinochloa crus-galli var. crus-galliArgentinaArgentina 201948 EPSP synthase inhibitors (G/9)
 		79Barnyardgrass18183
13 November 22, 2019Avena sterilis ssp. ludovicianaAustralia (New South Wales ) AustraliaNew South Wales 20181 EPSP synthase inhibitors (G/9)
 		30Sterile oat18186
14 October 24, 2019Capsella bursa-pastorisNorwayNorway 201931 ALS inhibitors (B/2)
 		41Shepherd's-purse18169
15 October 1, 2019Carduus acanthoidesArgentinaArgentina 201948 Multiple Resistance: 2 Sites of Action
EPSP synthase inhibitors (G/9)
Synthetic Auxins (O/4)
 		348Plumeless Thistle18173
16 September 24, 2019Oryza sativa var. sylvaticaColombiaColombia 201810 ALS inhibitors (B/2)
 		242Red Rice18170
17 September 2, 2019Rapistrum rugosumSpainSpain 201838 ALS inhibitors (B/2)
 		142Turnipweed18171
18 August 19, 2019Conyza sumatrensisTurkeyTurkey 201971 EPSP synthase inhibitors (G/9)
 		65Sumatran Fleabane18164
19 August 5, 2019Lithospermum arvenseChinaChina 20199 ALS inhibitors (B/2)
 		341Corn Gromwell18168
20 July 31, 2019Chloris radiataColombiaColombia 201910 EPSP synthase inhibitors (G/9)
 		340Radiate Fingergrass18165
21 May 13, 2019Galinsoga parvifloraFranceFrance 201817 ALS inhibitors (B/2)
 		339Gallant Soldier18162
22 May 13, 2019Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 EPSP synthase inhibitors (G/9)
 		65Sumatran Fleabane18161
23 January 9, 2019Amaranthus palmeriUnited States (Kansas) United StatesKansas201845 Synthetic Auxins (O/4)
 		14Palmer Amaranth18151
24 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Washington) United StatesWashington201845 Long chain fatty acid inhibitors (K3/15)
 		110Italian Ryegrass17154
25 December 15, 2018Lolium perenne ssp. multiflorumUnited KingdomUnited Kingdom 201844 Long chain fatty acid inhibitors (K3/15)
 		110Italian Ryegrass17153
26 December 15, 2018Lolium perenne ssp. multiflorumFranceFrance 201817 Long chain fatty acid inhibitors (K3/15)
 		110Italian Ryegrass17152
27 December 15, 2018Lolium perenne ssp. multiflorumUnited States (Oregon) United StatesOregon201845 Long chain fatty acid inhibitors (K3/15)
 		110Italian Ryegrass17151
28 November 9, 2018Bidens subalternansParaguayParaguay 201846 EPSP synthase inhibitors (G/9)
 		194Greater Beggarticks17150
29 October 10, 2018Conyza canadensisUnited States (Oklahoma) United StatesOklahoma201845 ALS inhibitors (B/2)
 		61Horseweed17149
30 October 2, 2018Conyza sumatrensisAustralia (Queensland) AustraliaQueensland20181 PSI Electron Diverter (D/22)
 		65Sumatran Fleabane17148
31 July 16, 2018Oryza sativa var. sylvaticaMalaysiaMalaysia 201828 ALS inhibitors (B/2)
 		242Red Rice17145
32 April 2, 2018Amaranthus palmeriUnited States (Oklahoma) United StatesOklahoma201845 EPSP synthase inhibitors (G/9)
 		14Palmer Amaranth17134

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