Putting The Bite On Melaleuca: UF And USDA To Release Australian Insect To Control Invasive Tree In South Florida

Published: April 19 2002


FORT LAUDERDALE, Fla.—To slow — and hopefully stop — the spread of harmful Australian melaleuca trees in South Florida, researchers from the University of Florida and U.S. Department of Agriculture will release a tiny insect predator Monday at the eastern edge of Everglades National Park in Broward County.

“After 16 years of research on natural or biological controls for the invasive tree species, we are releasing the melaleuca psyllid to help control or eradicate melaleuca,” said Susan Wineriter, a senior agricultural biologist with UF’s Institute of Food and Agricultural Sciences in Gainesville.

“The psyllid, about the size of a gnat or small ant, feeds on melaleuca’s clear sap, severely damaging seedlings,” she said. “It’s not a threat to people, animals or other plants.”

The melaleuca psyllid (Boreioglycaspis melaleucae) is the second beneficial insect imported from Australia to control melaleuca. In 1997, a weevil (Oxyops vitiosa) was released and is helping control melaleuca by feeding on leaves and flower buds. Seed production has been reduced by about 50 percent on trees they attack.

“Unlike the weevil, which is restricted to dry habitats, the melaleuca psyllid can invade in any melaleuca habitat,” Wineriter said. “We expect this will provide more effective control of the tree.”

The Australian tree species was introduced to Florida in the mid-1880s. Since then, it has spread quickly throughout South Florida, displacing native plant and animal communities, drying up wetlands, creating fire hazards and threatening the stability of the Everglades ecosystem, she said.

Attempts to control melaleuca with herbicides and mechanical methods have been expensive and not always successful. In fact, cutting or mowing the trees seems to spread tree seeds even more.

“USDA and UF scientists have been seeking effective biological control agents for melaleuca since 1986,” said Gary Buckingham, an assistant professor with UF and an entomologist with USDA’s Agricultural Research Service in Gainesville. “Since melaleuca trees are native to Australia, we searched for and found natural insect predators in that country.

“The release comes after an extensive quarantine period and careful testing to make sure the insect will not become a problem in South Florida’s fragile environment. Similar precautions were used before we released the weevil in 1997,” Buckingham said.

Other UF researchers working on the biocontrol research project include Robin Giblin-Davis, professor and associate center director of the Fort Lauderdale Research and Education Center, Min Rayachhetry, assistant scientist at the center, and Howard Frank, professor of entomology in Gainesville. Dale Habeck, professor emeritus of entomology, helped start the project in 1986.

The Monday afternoon release of the natural predator will follow groundbreaking ceremonies for a new $6.2 million USDA Invasive Plant Research Facility at UF’s Fort Lauderdale center.

Ted Center, leader of the new invasive plant research facility, said it will provide USDA and UF with a valuable resource to help contain melaleuca and other invasive species in South Florida.

The 21,000-square-foot facility is a cooperative project involving UF and three federal agencies. When completed in February 2003, it will be owned and operated by USDA at UF’s Fort Lauderdale center. In 2001, the U.S. Department of the Interior, which is responsible for the overall Everglades restoration plan, provided funds to the Army Corps of Engineers to construct the facility.

Center, who received his doctoral degree in entomology from UF’s College of Agricultural and Life Sciences in 1976, said the Florida Everglades is one of the nation’s most valuable ecosystems, but also one of the most endangered. He said the research facility will help state and federal efforts to restore the Everglades.

Those expected to participate in the groundbreaking ceremonies include USDA Deputy Secretary Jim Moseley, Interior Department Secretary Gale Norton and U.S. Rep. Clay Shaw (R-Fla.). Other participants include Mike Martin, UF vice president for agriculture and natural resources; Van Waddill, director of UF’s Fort Lauderdale center; Les Brownlee, acting assistant secretary of the Army; Col. Greg May of the U.S. Army Corps of Engineers, Jacksonville District.


Susan Wineriter, spitz@ufl.edu, 352-372-3505 ext. 166
Gary Buckingham, grbuck@nervm.nerdc.ufl.edu, 352-372-3505 ext. 124
Robin Giblin-Davis, giblin@ufl.edu, 954-577-6333
Ted Center, tcenter@saa.ars.usda.gov, 954-475-0541