LARGO

Around these parts, the air potato vine is considered a noxious and evil weed. Native to Asia and Africa, this invasive species can grow 70 feet in a single summer, choking the life out of native plants.

"They're nasty. They're not easy to kill. They laugh at Roundup," says Largo parks superintendent Greg Brown.

So Largo is resorting to biological warfare. On Tuesday, it released 300 air potato leaf beetles into four of its parks. Originally from Nepal and China, the critters dine exclusively on air potato leaves.

They came courtesy of the state, which launched a program this year to disseminate the beetles all over Florida. Officials are assuring Floridians that the beetles won't become an invasive pest themselves.

"You don't want to put something out there that's going to create another problem," said Eric Rohrig, an entomologist with the Florida Department of Agriculture and Consumer Services. "They studied it in quarantine for four years. The only way you can release an exotic insect is if you can prove that it doesn't feed on any other plants."

The air potato, Dioscorea bulbifera, is an invasive twining vine with big heart-shaped leaves that can engulf the canopies of trees, eventually killing them. It steals sunshine, water and nutrients from the plants that actually belong here.

It's an exotic species like Brazilian peppers, Burmese pythons, kudzu, melaleuca, skunk vine, the red bay ambrosia beetle and the walking catfish. Every year, the state spends millions of dollars trying to contain these species.

The newest weapon against the air potato: Lilioceris cheni, the air potato leaf beetle. The red insect looks a little like a ladybug but without its black spots.

The state, which is partnering with the U.S. Department of Agriculture, has been busily reproducing the beetles in a lab in Gainesville. So far this year, it has released more than 30,000 of the bugs in 16 Florida counties, including Hillsborough and now Pinellas.

"This is the first year we started doing widespread releases," Rohrig said.

The first bugs arrived in Pinellas County on Tuesday when Largo received a shipment of 300 beetles in a cooler full of plastic containers. Officials quickly released them on air potato infestations at Largo Central Park Nature Preserve, McGough Nature Park, Bonner Park and the city's new Highland Recreation Complex.

"We spend thousands of dollars and volunteer hours on 'potato pulls.' The air potato vines get intertwined way up in 30- or 40-foot-tall trees. They reduce biodiversity in the nature parks," Brown said, adding that some infested spots in Largo's parks look like "moonscapes."

"It's all over the place," said Jane Morse, a horticultural extension agent with the University of Florida and Pinellas County Extension. "It takes over areas and disrupts the whole ecological function of the plant environment, and that affects your wildlife as well."

Initially, the state is dispersing the beetles to public parks, nature preserves and forests. In time, officials plan to release them in residential areas as well.

No one expects an overnight success.

"These types of things aren't a quick fix," said Rohrig, the state entomologist.

But on Tuesday, as the bugs were plopped onto air potato vines all around Largo, something noticeable happened.

They started chewing.

Mike Brassfield can be reached at brassfield@tampabay.com or (727) 445-4151.