Die, Weed, Die!

In the center of the property, however, lies a roughly twenty-acre section that's been left untreated. Deep inside is the test plot Van and Rayamajhi routinely monitor to measure the effects of the bioagents.

They weave their way about 50 feet into the thicket. "Look at this one," says Rayamajhi as he grasps a small melaleuca shrub with a rusty color on its leaves. "It got hit by disease, and it's trying to grow back. The rust is disease. This one got hit by weevil."

Van picks up what looks like a miniature brown cob of corn. This is the melaleuca seed fruit. Each of its hundreds of "kernels," which are the size of a needle head, can hold about 400 seeds.

Even the tallest trees are at risk from the good weevils. As trees grow bigger, they require more nutrients via photosynthesis. Thus a large canopy of leaves is essential. "The food production goes down because the insects feed on leaves and disease hits the trees," Rayamajhi says. "The tree diverts its energy to fight the insects, and then it doesn't have enough food to reproduce. Then they'll die. People wonder how little bugs can kill these big trees, but they're actually very vulnerable."

Their research has been enough to convince even skeptics that bioagents are a real alternative to spraying. "We needed to convince the state agencies that this was a long-term alternative to chemicals," Rayamajhi says. "At the beginning we didn't have the funding to disperse the insects, but now they've reallocated some of the chemical funds to insects."

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In late 2000, John Volin, an infectiously energetic plant scientist at Florida Atlantic University, began looking at the steady growth of Old World climbing fern. Little was known about its biology. Not until 1978 was its spread scrutinized by two scientists, who found it growing near the shoreline in southern Martin and northern Palm Beach counties. They concluded the spore-bearing plant was a cause for worry.

No one became worried.

The fern, however, spent the next fifteen years diligently establishing itself in the undergrowth, then climbing upward, and finally coiling around tree branches and leaves. Starved of sunlight, the trees slowly died. The South Florida Water Management District, a state agency that's a front-line warrior against invasives, began aerial surveys of the fern in 1993 from coast to coast at 500 feet above treetops. By the end of the decade, the water district had data indicating the fern had spread to Florida's west coast and was overwhelming the tree islands of the Loxahatchee National Wildlife Refuge in south Palm Beach County.

What, Volin wondered, was the Everglades facing?

Using the data collected between 1978 and 1999, Volin devised a computer model to project the spread of the climbing fern by the year 2014. Despite knowing how rapidly the plant had multiplied, Volin was stunned by what he found. The model revealed the fern will have covered almost all the Everglades in Palm Beach, Broward, Hendry, and Collier counties. Substantial portions of Martin and Glades counties will have been covered, and the infestation will have made deep inroads into Everglades National Park in Miami-Dade County.

Volin's findings seemed too dire to be true. "I said, 'Hell, we can't share this,'" Volin recollects. So before announcing the findings in 2002, Volin and his research assistants double-checked the reliability of his prediction through painstaking marches through the Everglades. "I feel strongly that, as a physiological ecologist, when we're doing predictions -- whether it's about climate change or, in this case, an invading species -- you don't want to overstate it," Volin says. "It's like saying the sky is falling. You don't want to do some dire prediction, only to eat your words later on."

No one's calling Volin a Chicken Little.

Don Schmitz, with the Florida Department of Environmental Protection's invasive plant bureau, estimates state agencies are spending more than two million dollars a year to combat Lygodium, about eight times more than five years ago.

The Loxahatchee Refuge recently received four million dollars from Congress to fight exotics, Melvin says, and the threat of Old World fern certainly helped loosen those purse strings for tree triage. "There will be aerial spraying of islands where there aren't any native plants left and follow it up with a ground crew on the perimeter," she says.

Volin, who possesses a bantam build, impressively full goatee, and piercing eyes, is overseeing another ambitious year-long project, funded by the water district, to hunt down incipient sporelings of Old Word fern in the east-central part of the Everglades. His research team will visit each of the roughly 500 islands and, using a GPS device, record each sighting of the fern. The management district will then send out contractors who will locate the exact spot and treat the plant with a systemic herbicide that completely destroys it. It's an endeavor analogous to bicycling across the U.S. to visit every 7-Eleven: They're everywhere and you never know where the next one will spring up. Just how much this will cost won't be known until later.