Wasps Released in La. to Combat Bugs

METAIRIE, La. (AP) ─ Louisiana horticulturists tied a small cylindrical vial containing hundreds of gnat-sized wasps to a hibiscus plant on a well-groomed lawn Wednesday, and removed the cap.

Once airborne, the wasps were almost invisible to the naked eye. But tiny as they are, the non-stinging wasps are the state's biggest ally in eradicating a pest ─ the pink hibiscus mealybug ─ that's made its way to the state.

Native to Africa and Asia, the mealybugs attach themselves to plants and suck out the sap and nutrients, eventually killing the plant. They leave behind a lumpy white residue that resembles Christmas tree flocking.

In recent weeks, the state tested plants in parts of Jefferson Parish reported to have signs of infestation. Almost 40 tested positive in Metairie, Kenner and Marrero. That has agricultural officials concerned because the tiny mealybugs can destroy more than 10,000 kinds of plants, including agricultural crops.

"They can attack sugarcane. They can attack citrus crops. They can do a lot of damage,'' said state Agriculture Commissioner Bob Odom, who was at one of the wasp-release sites.

The bugs have been reported in only two other states ─ California and Florida ─ both of which have managed to control the pests with parasitic wasps. A wasp will puncture the bug and lay eggs in it. Once deposited, the larvae feed on the bug internally, causing it to die.

State agriculture officials imported thousands of the wasps from facilities in California and Puerto Rico, where they're raised for the government. The wasps are the most effective and natural way to combat mealybugs, and because they don't sting, they pose no threat to humans, Odom said.

Odom and a group of state horticulturists deposited thousands of the wasps, hundreds at a time, in affected neighborhoods on Wednesday.

Their first stop was the Metairie home of Jan Gourgues, who looked on as a horticulturist tied two vials with about 200 wasps in each to the mealybug-infested hibiscus on her front lawn.

Gourgues said she knew something was wrong a few months ago when her hibiscus plants didn't bloom this summer for the first time in years, and their leaves started to curl and fall off prematurely. Then she noticed a lumpy white coating on the stems and branches.

"I thought it was a fungus,'' she said.

Odom asked that homeowners in Jefferson Parish not use pesticides or other wasp treatments while the wasps are being released. He said the wasps will be released on a weekly basis in infested neighborhoods for several weeks.

• Image: The Scent of a Bug
• Invasive Creatures Attack Like Internet Viruses
• Images: Invasive Species