East Liverpool, OH is in Columbiana County which is in Northeast Ohio. Look it up.
If you question the isertion about marijuana being grown in the Wayne National Forest, it can be confirmed by a call to the Athens County Sheriff Dept. (WT-en) 2old 14:37, 11 September 2007 (EDT)
Out of curiosity, I checked several regions of California, for example, the North Coast, home to "Humbolt County, Ca." that made no specific mention of marijuana farming on public lands.
Which makes me wonder, is this warning REALLY required for a national forest in South East Ohio?