"Invasive insects and diseases have killed MILLIONS OF TREES in Michigan–often after hitching a ride on firewood. Please don’t transport firewood! At most campgrounds, it can be purchased on the premises or from nearby vendors who sell USDA-certified firewood. If certified firewood is not available, purchase your firewood as close as possible to where you will burn it. If you purchased wood and don’t use it all, remember–don’t transport it or take it home with you. "
Correct, they're trying to stop the spread of invasive species.
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