(CNN) -- The U.S. Forest Service is urging hunters and fishermen to keep their eyes open for marijuana growing operations in Wisconsin's Chequamegon-Nicolet National Forest. Since 2008, nine marijuana growing operations have been discovered on public land within the state. Most recently, in late August, a fisherman visiting the forest happened upon a marijuana field that netted more than 8,000 plants worth $8 million. "The fisherman was walking along the banks of the Oconto River and noticed these patches that had been cleared and disturbed. Trees were down, things didn't look right, and he reported that to authorities, and a surveillance operation was established," said Jane Cliff, a spokeswoman for the U.S. Forest Service eastern region.
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80,000 marijuana plants eradicated in Wisconsin forest
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Many of those arrested in busts are in the country illegally
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U.S. Forest Service wants hunters, fisherman to flag any suspicious areas
@placeholder is targeting illegal marijuana growers because it has millions of acres of remote public land.