Daryl Lease is an editorial writer at the Herald-Tribune in Sarasota, Fla. His e-mail address is daryl.lease@herald-trib.com.

Earlier this year, U.S. drug czar Barry McCaffrey tried to wheedle promises from Hollywood to make films preaching the horrors of drug use. Meanwhile, he and an unusual team of collaborators were hurriedly writing an anti-drug script of their own.

Their drama -- let's give it a blockbuster title "Fungus!" -- is set in the Amazonian jungle, and McCaffrey's people describe it as a can't-miss international hit. Others, however, are making a persuasive case that it will be a B-grade horror flop, more deserving of a title like "Hey! Who Ate the Rainforest?"

Florida learns its lesson

The fungus in question is Fusarium oxysporum, a relatively unknown actor with a voracious appetite for marijuana, cocaine, heroin and -- according to some critics -- just about anything leafy, green and unable to pull up roots and flee.

Last summer, Florida officials briefly, and rather theatrically, pondered experimenting with this soil-borne fungus as an alternative means to combat the state's thriving marijuana trade. Promoters touted it as a lean, mean weed-eating machine, but skeptics accurately noted that precious little is known about what else it might munch in the process.

David Struhs, appointed by Gov. Jeb Bush to head the Department of Environmental Protection, joined a chorus of opponents -- including a predictably off-key contingent of potheads -- in denouncing the fungus plan as risky and perhaps foolhardy. Struhs warned Jim McDonough, who had traded his title as director of strategy for McCaffrey to become Florida's drug czar, that the Fusarium species is "capable of evolving rapidly" and may prove "difficult, if not impossible, to control."

"The mutated fungi," Struhs wrote, "can cause disease in a large number of crops, including tomatoes, peppers, flowers, corn and vines, and are normally considered a threat to farmers as a pest rather than as a pesticide." In the steamy soil of Florida, the fungus could live for decades.

We have been down this road before. In several notorious attempts to put species from other countries to work in the United States, we were startled to discover that the plants take on wildly different personalities in our environment.

Kudzu was originally introduced to the southern United States from China as a natural means of erosion control, but it has overwhelmed native species. Punk trees, or Melaleuca quinquenervia, were imported to help dry up the Everglades back when some folks thought that was a dandy idea. The trees marched relentlessly onward and continue to suck up water wherever they please.

"I personally do not like the idea of messing with Mother Nature," said Bill Graves, senior biologist at the University of Florida Research Center, told The New York Times last summer, shortly before state officials shelved the idea. "I believe that if this fungus is unleashed for this kind of problem, it's going to create its own problems. If it isn't executed effectively, it's going to target and kill rare and endangered plants."

An unwelcome risk

Fast forward to this summer, as President Clinton delivers a controversial $1.3 billion anti-narcotics aid package to Colombia. Much of the debate has focused, understandably, on Colombia's human-rights record and whether the U.S. military is entangling itself in a far stickier mess than might appear.

Those controversies are overshadowing the fact that the package includes $3 million to test the effectiveness of Fusarium oxysporum on Andean coca bushes. McCaffrey and other supporters of the experiment hope it will demonstrate that the mycoherbicide, or fungal herbicide, is safe and can quickly be put to work destroying Colombia's estimated 300,000 acres of coca.

There have been at least two instances of the fungus laying waste to coca plants. In the 1970s, Coca-Cola began growing coca in Hawaii to use in its flavoring process, but a fungus later identified as a strain of Fusarium oxysporum destroyed the crop. In 1992, Peru's cocaine producers lost thousands of acres to the fungus.

Not all Colombian officials are thrilled with the idea. Colombia's environmental minister, Juan Mayr, told The New York Times that he opposes the tests "because any agent foreign to the native ecosystems of our country could present grave risks to the environment and human health."

In a lengthy, ground-breaking piece in its May issue, Mother Jones magazine recounted, among other things, research indicating that the same strain of fungus that wiped out the coca plants in Peru also killed banana and other food crops. Writers Sharon Stevenson and Jeremy Bigwood also raised alarms about the U.S. government's supposedly reassuring claims that the fungus will attack only plants within the genus Erythroxylum -- a genus that includes more than 200 plants besides coca.

McCaffrey's office says more than 100 species of plants have been tested with the fungus and none has been affected. But that is only a tiny fraction of species contained in the Amazon jungle, the second-most biodiverse region in the world.

In addition to the environmental concerns, opponents in Colombia and elsewhere have pointed to studies indicating that the fungus can be toxic to humans under some circumstances. McCaffrey's office contends that the toxins would affect only "immune-suppressed cancer patients whose defense levels were very low, making them vulnerable to almost any microbe." Those folks, McCaffrey's report says, would be hospitalized or quarantined and thus out of the way during spraying.

Coming to a theater near you?

Despite pleas to stop McCaffrey's blockbuster production, the experiment is about to begin. The cheering squad now includes at least a few Florida politicians. Rep. Bill McCollum, a Republican who hopes to win a seat in the Senate this fall, says the fungus could be "the silver bullet" in the drug war.

Perhaps he is correct, and Fusarium oxysporum will be one of those rare instances in the history of government where the law of unintended consequences will be temporarily suspended. Maybe we really are looking at major turning point in the war on drugs.

But we should be sure to bring plenty of extra popcorn to McCaffrey's show. The fungus may well appear on our doorsteps in mid-viewing -- with a really bad case of the munchies.