The Bluegrass State's No. 1 Cash Crop: Dope

About an hour's drive from Lexington, Ky., is the Daniel Boone National Forest -- 700,000 acres of raw, rugged nature.

It was here last month that the body of Bill Sparkman, a part-time census worker, was found bound and gagged and hanging from a tree. The word "Fed" was scrawled across his chest.

"I couldn't believe it had happened," said Josh Sparkman, the victim's son. "I couldn't believe that anyone would want to harm my father, especially in such a brutal manner."

Sparkman's death is still being investigated. It has not been ruled a homicide.

But it's put renewed focus on what, for decades, has been the ugly side of this beautiful land.

It's not the setting most people associate with the war on drugs.

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"Typically, in America today, they talk about the inner cities and people standing on street corners selling crack cocaine," said Clay County Sheriff Kevin Johnson. "This is our street corner. Here."

Johnson took an ABC News team deep into the forest. During the days of Prohibition, criminals made illicit alcohol -- moonshine -- here. But these days, marijuana and methamphetamine keep authorities busy.

Rich soil and ample rain make the forest ideal for growing pot. And the forest's thick canopy, rugged terrain and sheer size help to conceal criminal operations.

Johnson said the silence of the nature preserve makes it harder to police.

"That's one aspect that makes things difficult in apprehending people," he said. "For example, if somebody's 100 yards uphill from us, that they would have a potential of hearing us. Not to mention, the vehicle that we drove, they could hear a mile away."