Running stop sign @ railroad crossing

Would like to know if I can get out of ticket for not stopping @ stop sign at railroad crossing. The issue is that trains no longer use this railroad (bushes and trees are growing all over). Officer quoted violation as Iowa code 321.342 which has wording “across which traffic is regulated”(see link below). But there is no traffic that is regulated…and hasn’t been for years. Any chance to get out of $330 fine?
http://coolice.legis.iowa.gov/cool-ice/default.asp?category=billinfo&service=iowacode&ga=83&input=321.342