Kenya RPCV William Overholt and Honduras RPCV Ronald Cave are attacking the exotic plants and pests that destroy Florida's native growth and crops
SPACE INVADERS
Feb 23, 2003 - Palm Beach Post
by Libby Well, Palm Beach Post Staff Writer
William Overholt and Ronald Cave are highly skilled biological control experts who just got new marching orders. Their mission: Attack the exotic plants and pests that destroy Florida's native growth and crops.
Their weapon: bugs.
Overholt and Cave are Ph.D.s of entomology who recently joined the University of Florida's Institute of Food and Agricultural Sciences at the Indian River Research and Education Center.
Their job is to find the insects that are the natural enemies of invasive species. Both men are Peace Corps veterans and have worked extensively in foreign countries. Overholt relocated from Kenya; Cave was in Honduras.
In May 2004, the university expects to have a new $3.8 million quarantine facility for Cave and Overholt's research. The tightly secured quarters will allow the scientists to isolate arthropods and make sure they destroy only the alien plants or bugs that damage indigenous growth.
"The facility and program represent another significant addition to the research capabilities of the Treasure Coast," the center's interim director, Walter Tabachnick, said at the groundbreaking in October.
Invaders use ports, airports
Entomologists are in demand in Florida, where more than 30 percent of plants are exotic. Only Hawaii has more invaders, Overholt said.
"The Miami ports and airport are a big source of these, as are shipping containers," he said.
Overholt's focus is nonnative plants, while Cave will be researching invasive insects.
Among Overholt's targets are the Brazilian pepper tree, a pretty exotic with red berries that thrives along canals, highways, telephone lines and creeps into orange groves.
"It takes up space where native plants would go," Overholt said. "And it's allergenic. It's related to poison ivy and oak. Some people get rashes and have trouble breathing."
A UF entomologist in Gainesville has imported and quarantined several insects that feed off the tree. When the federal government grants permission, Overholt will release the bugs and do follow-up studies.
He also is examining West Indian marsh grass, which is displacing native species on the west side of Lake Okeechobee, and the air potato, a vine that smothers growth in yards, pine lands and hardwood hammocks. Overholt is going to the West African country of Ghana in May to look for insects that control air potato.
Cave's job is to hunt down the arthropodal foes of a Mexican weevil that destroys bromeliads, an East Indian bug that munches on grapefruit leaves and native plants, and an Asian scale insect that attacks sago palms.
"We want to bring in the good bugs to fight the bad bugs," he said.
Fly could wipe out weevil
Bromeliads, known as air plants, are popular as house plants and for decorating and landscaping. Ten native species of bromeliads are threatened or endangered. They provide a haven for frogs, spiders and other creatures.
"There are vertebrates and invertebrates using it as a house," Cave said.
Cave believes a Honduran fly, which Gainesville scientists have quarantined, might be the agent that can take out the "evil weevil" from Mexico.
"The fly larva burrows into the weevil larva and lives there and kills it," he said.
To battle the scale insect that covers sago palm leaves like snow, Cave is looking for parasitic wasps from southern China, Taiwan and Vietnam. He is also seeking the enemies of a gray weevil that hails from India and makes its second home only in South Florida. The weevil feasts on crepe myrtle, orchid trees and many other native plants.
Scientists say residents can help eliminate invasive species.
"People should be aware of what's in their yards and know how to control it or get help," Overholt said. "Cut down the Brazilian pepper tree and treat it with herbicides. Cut out the air potato."
Farmers or homeowners who don't know what exotic species look like or how to get rid of them can contact their county extension office, where horticulturists and master gardeners can help identify bugs and plants.
"Identification is always the first step," said Ed Skvarch, commercial horticulture agent for the St. Lucie County extension office. "If we don't know what we're up against, we can't decide what our control measure is going to be. If a question can't be answered over the phone, put a sample in a bag and bring it in."
For information
If you have a plant or bug in your yard, garden or farm you can't identify, or if you need help eradicating invasive species or treating an ailing plant, call your local county extension office:
- Martin County: 288-5654
- St. Lucie County: 462-1660
