Have you ever tried to spot a marijuana patch from a helicopter? I have. It's a lot like trying to find a green Waldo in a barrel full of pickles.

As a weekly newspaper editor in Central Kentucky, I spent many a sticky August afternoon aboard drug task force choppers - thwack, thwack, thwacking, low over the knobs, scanning the wind-whipped vegetation below for a certain shade of "marijuana green." Summertime for a decade meant hacking through the brush with Marion County sheriff's deputies or huffing and puffing behind state police troopers in Washington County - searching the hills and hollows for marijuana.

And I am here to report that tracking down "home grown" in Kentucky is a tough job. Dopers are slicker than boiled okra at hiding their crops. They split them up, growing a few plants here and a few there. They grow crops indoors in hydroponics beds, outdoors amid rows of corn, or hide plants on somebody else's property. They have all the time and energy in the world to invest in figuring out the best way to disguise a crop that will make them rich if even a small portion of it ever hits the streets.

So when I hear people talk about allowing farmers to grow industrial hemp in the fields of Kentucky - how it would be a great cash crop to replace tobacco, no problem to regulate, and no trouble for police officers to distinguish from it's cousin, marijuana - I'm not at all convinced those folks' dipsticks touch oil.

At issue here is tetrahydrocannabinol, or THC. THC is the psychoactive component of the cannabis plant - the part that produces the buzz, the munchies, the distorted sense of time and distance. All cannabis plants contain some THC. Hemp quality cannabis contains a small amount; marijuana quality cannabis contains a whole lot.

But Michael Troop, U.S. attorney for the Western District of Kentucky, has pointed out that even the low levels of THC found in most hemp quality cannabis plants are comparable to the levels of THC in the marijuana produced during the 1960s and 1970s.

And that's how marijuana growing found its way to the Central Kentucky knobland. When farm boys from Marion and Washington counties were sent to Vietnam, they discovered that the tall, leafy hemp plants growing wild behind grandma's barn back home contained the stuff fellow soldiers were smoking in Saigon - smoking and paying big, big money for.

The result was the rise of a mammoth marijuana - growing industry. For much of the 1980s, the single largest cash crop in Marion County was not tobacco but marijuana. The easy money bred greed and evil like a fly breeds maggots

Ask any Washington Countian about Rottweiler puppies with the larynxes slashed, and they'll tell you in hushed tones about the dope grower who didn't want raiders of his pot fields to hear his guard dogs coming.

Ask any Marion Countian about marijuana - bought mansions, marijuana - bought trucks, marijuana - bought police detectives, about little kids finding thousands of dollars in an abandoned barn, and about a whole generation of farm boys who will be middle aged before they see the outside of federal prison.

Ask any Kentuckian about the Corn-bread Mafia, the largest domestic marijuana - producing operation in the history of the United States. Police made 56 Corn-bread Mafia arrests in five states, 54 Marion Countians and two from Washington County - men who vanished into 20 year prison terms, leaving behind corrupted communities and shattered families.

Why don't you ask those families whether they think it's a good idea to introduce industrial hemp into Kentucky again as a cash crop?

Try telling them that law enforcement officers wouldn't end up having to test every plant in afield for its THC level before they could make a bust.

Try convincing them that a new generation of enterprising dope growers wouldn't figure out some way to hide home grown in fields with its less-lethal cousin.

See if you can get them to believe that convicting a farmer who claimed he had "no idea" there were half a dozen marijuana plants growing in his 100 - acre hemp crop wouldn't be like nailing Jell-O to a barn wall.

But don't try to convince me. I've spent too many hot August afternoons searching a windswept sea of green, looking for an evil that corrupts every life it touches. I've seen the damage marijuana can do before anybody ever strikes a match to it. (Source: Lexington Herald-Leader, Lexington, Ky. Sunday, March 9, 1997. By Ninie O'Hara.)