According to WSSA the definition for herbicide resistance: is the inherited ability of a plant to survive and reproduce following exposure to a dose of herbicide normally lethal to the wild type. In a plant, resistance may be naturally occurring or induced by such techniques as genetic engineering or selection of variants produced by tissue culture.
According to WSSA the definition for herbicide tolerance: is the inherent ability of a species to survive ans reproduce after herbicde treatment. This implies that there was no selection or genetic manipulation to make the plant tolerant, it is naturally tolerant.
Weed Species Large Crabgrass Redroot Pigweed Smooth Pigweed Green Pigweed Giant Ragweed Common Ragweed Canada Ragweed
Chatham-Kent Group 1 Group 2 Group 5 Group 6 Group 7 Group 2 Group 5 Group 6 Group 2 Group 2 Group 2
Elgin Group 2 Group 6 Group 2 Group 5 Group 2
Essex Group 2 Group 6 Group 6 Group 2 Group 5 Group 6 Group 2 Group 9 Group 2 Group 9
Huron Group 2 Group 7 Group 2 Group 5 Group 2
Lambton Group 2 Group 2 Group 5 Group 2 Group 9 Group 2
Middlesex Group 2 Group 7 Group 2 Group 5 Group 7 Group 2
Oxford Group 2 Group 2 Group 5 Group 2
Perth Group 2 Group 2 Group 2
Weed Species Waterhemp Lamb’s-quarter Eastern Black Night Shade Canada Fleabane Giant Foxtail Green Foxtail Field Pepper Grass Cocklebur
Chatham-Kent Group 9 Group 2 Group5 Group 2
Elgin Group 2 Group 5 Group 2 Group 2 Group 9 Group 2
Essex Group 2 Group 5 Group 9 Group 2 Group 2 Group 22 Group 2 Group 22
Huron Group 5 Group 2 Group 2 Group 9 Group 2
Lambton Group 2 Group 5 Group 9 Group 2 Group 5 Group 2 Group 9 Group 2 Group 2 Group 2
Middlesex Group 2 Group 5 Group 2 Group 9
Oxford Group 5 Group 2 Group 2 Group 9 Group 2 Group 2
Perth Group 2 Group 2 Group 2 Group 9 Group 2
Legend: Example Herbicide(s) for each Group
Group 1: Assure ll
Group 2: Pursuit, Classic, Pinnacle
Group 5: Aatrex, Sencor
Group 6: Basagran, Pardner
Group 7: Lorox
Group 9: Glyphosate, Roundup Weathermax
Group 22: Reglone, Gramoxone