Many thanks for that link; will book mark as the question comes up with some frequency. To add to that just a bit, Oregon still allows what-ever footware but if you bring in a boat from out of State you MUST have it inspected for 'invasive species.'
About 4,500 inspections (last year was the first full year) and the Game Guys found FIFTY ONE boat trailers with 'Dear God's!' In two instances I'm aware of (fellows up from Redding, CA) 100+ degree temps and neither boat had seen water for at least two weeks.
That wasn't enough to kill the snails.