No. For Cal/West, contamination went from 3% in 2008 to 12% in 2009, because these are perennial plants. An alfalfa plant is planted and can survive for three to five to possibly ten years, and if it's a Roundup Ready alfalfa plant, it is there and for its whole life--for three, five or ten years--it will be releasing its pollen to other feral alfalfa or other non-conventional types.
On June 7th, 2010. See this statement in context.