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An infestation of Rugose spiraling whitefly covers shrubbery along A1A in Ocean Ridge. 

Photos by Jerry Lower/The Coastal Star

By Tim O’Meilia

Last winter was so warm that even one of South Florida’s most unwelcome visitors — the Rugose spiraling whitefly — decided to stay for the summer and bring his relatives.

Now some coastal landscapes look as if they’ve been decorated for Christmas in August. The leaves of native Florida gumbo limbo trees, the fronds of adonidia palms and dozens of other tree species are strung in white. 

The undersides of the leaves resemble a holiday decoration but there’s no cause for celebration. They’re whitefly eggs ready to develop and feed on the succulent leaves.

“They make the most beautiful patterns — perfect little round white circles like a crocheted tablecloth,” said Ocean Ridge resident Barbara Cook, who discovered the invaders on her gumbo limbo, strangler fig, kumquat and powderpuff trees a month ago.  

“My phone hasn’t stopped ringing,” said Laura Sanagorski, an environmental horticulturist with the University of Florida Palm Beach County Extension Service. “Two of every three calls are about Rugose spiraling whitefly.”

An infestation of spiraling whitefly can cause leaves to wilt, yellow and fall; but University of Florida scientists think healthy, mature plants will survive the attacks. But younger, weather-stressed plants may be more vulnerable. 

The whiteflies coat the leaves with a waxy white substance called flocculent and excrete a sticky substance called honeydew that falls on anything beneath the trees, including cars, patios and pools. 

The honeydew becomes the host for a sooty mold that further covers and stains. 

“In general, we see this whitefly as more of a nuisance than a threat,” Sanagorski said.  “We’re not seeing decline in the plants like we do with the ficus whitefly.”

Unlike the ficus whitefly, its more lethal cousin, the larger spiraling whitefly is the unpicky eater you wish your 3-year-old would become. 

“At first, we thought it was specific to the gumbo limbo but it has branched out,” Sanagorski said. The spiraling whitefly now has more than 90 species on its menu, including coconut palms. 

“It’s prevalent everywhere now,” said Christopher Trent Ward, owner of Aaron’s Environmental Services, who now spends several days a week dealing with the whitefly menace.

Christopher Trent Ward, owner of A. AAron’s
Environmental Services Inc., treats palms for whitefly
infestation at a condominium complex in South
Palm Beach. Jerry Lower/The Coastal Star

Ward treated Cook’s trees with a systemic pesticide spread around the trunk for the trees to absorb and with a spray on the leaves. “I haven’t had any defoliation, so I think we caught it in time,” said Cook, who is a certified master gardener. The treatments will continue every few months. 

Although there are more than 57 species of whitefly in Florida, the spiraling whitefly first arrived in 2009, in Miami-Dade County, probably from Central America. It has made its way up the coast with an explosion of growth beginning last winter, likely because of the warm temperatures.

Based on anecdotal reports, the spiraling whitefly tends to move up the coastline before heading inland. “They seem to do a lot better near water — near the coast or close to the Intracoastal [Waterway],” said Kris Wilson, pest control manager for O’Hara Pest Control in West Palm Beach. 

“When we have a new pest, the first couple of years we see an explosion of growth. The new pest has few natural enemies and it takes some time for them to develop,” Sanagorski said. “It’s pretty happy here now.”

The University of Florida is studying some ladybug-like beetles and several parasitic wasps that hold some promise in containing the whitefly, but nothing is on the commercial market yet.

Both Aaron and O’Hara use systemic insecticides absorbed through the roots so other beneficial insects won’t be harmed but sprays are used if necessary. Neither uses injections directly into the trunks of trees because they say it’s not recommended by the University of Florida horticulturists. 

However, several pest control firms do use the injection method. The town of Palm Beach recently spent more than $24,000 injecting and spraying vulnerable town-owned ornamentals.

“Palm Beach is being very active and definitely wanting to do it the right way,” Sanagorski said.

The town of Ocean Ridge recently followed Palm Beach’s example and approved an ordinance requiring residents to remove dead or dying foliage due to spiraling and ficus whitefly and other pests. Residents have two months to try to treat their plants before removing them. 

Palm Beach residents face a $250-a-day fine, but Ocean Ridge leaves the punishment up to its code enforcement board. 

“It’s been a problem,” Ocean Ridge Town Manager Ken Schenck said of the whitefly, the ficus species in particular. “What we didn’t want was for residents to jeopardize their neighbors.”