Influence of herbicide-resistant canola on the environmental impact of weed management.

The growth of herbicide-resistant canola varieties increased from 10% of the canola area in Canada in 1996, when the technology was first introduced, to 80% in 2000. From 1995 to 2000, the amount of herbicide active ingredient applied per hectare of canola declined by 42.8% and the Environmental Impact (EI) per hectare, calculated using the Environmental Impact Quotient for individual herbicides and the amounts of active ingredients applied, declined 36.