Its 2004 and I'm cleaning off my desk. 2 years ago, while headed to Maine, with the Mac in tow, we were handed a pamphlet about invasive plants on trailers. This isn't a problem when sailing in salt water.
But Maine is the only state without invasive plants in their lakes. They are making an effort to keep it that way. The pamphlet remindus us that it is illegal to transport plants on trailers, boats, or in fishing gear.
The state now also requires all boats on inland lakes to purchase a "Lake and River Protection Sticker" The cost is $10 for residents and $20 for non residents. Below is a link to the state web page. The page has information about purchasing stickers.
State of Maine web page