Awareness of local plant diseases will really help protect your investment-Stefan
Posted: 5:40 a.m. Thursday, Aug. 16, 2012
Whiteflies Hit Palm Beach County Homeowners’ Trees, Plants, Pools
Palm Beach Post Staff Writer
The Rugose spiraling whitefly is wreaking havoc throughout Palm Beach County, damaging landscape plants and trees and leaving a sticky excrement called honeydew and its accompanying sooty mold on patios, walkways, outdoor furniture and vehicles.
“They have pretty much infested everything I have,” said West Palm Beach resident Christopher Collier. “They look like white polka dots on every leaf of everything. It’s ugly in and of itself.”
His Christmas palms, birds of paradise plants and a banana tree were covered with a white, waxy material called flocculent that looks like fluffy dandruff. Collier’s swimming pool was full of dead whiteflies, honeydew and wax.
“The pool looks like it has snow in it,” Collier said.
The spiraling whitefly, first detected in the U.S. in Miami-Dade County in March 2009, has been making its way north. It’s not the same insect as the ficus whitefly, which has destroyed many ficus hedges and cost homeowners thousands of dollars to combat it. University of Florida experts say the spiraling whitefly does not kill healthy, mature trees, but the long-term effects of multiple infestations are not known.
“The Rugose spiraling whitefly is taking center stage these days. It definitely makes more of a mess than the ficus whitefly. It is more noticeable. It’s an omnivore,” said Laura Sanagorski, a UF Palm Beach County Extension environmental horticulturist.
“There are plants we have not found it on yet, for sure. We are looking at it like there is nothing it won’t reproduce on. It’s got its favorite plants as far as really establishing itself and causing damage with the wax and the honey dew to the point that it is really an issue,” Sanagorski said.
The whitefly prefers gumbo limbo trees, coconut palms, birds of paradise and black olive trees, and will probably appear on those first. But it also can be found on hibiscus, sea grapes and dozens of other plants.
The extension service is recommending the use of systemic products in the neonicotinoid family, applied to the soil or trunk rather than the foliage. That way the beneficial insects which eat or parasitize the whiteflies by laying eggs inside the juvenile form of the pest will have a chance to do their job.
“Ideally, someone will be scouting their landscape once or twice a week and taking a quick look around. If you can catch the problem sooner rather than later, it is much easier to control,” Sanagorski said.
The insects typically feed on the underside of leaves.
John FitzGerald, a lawn and ornamental department supervisor at Tomasello Pest Control in West Palm Beach, said the whitefly infestation seems to be getting worse.
“I’ve been in business over 50 years. I’ve never dealt with anything like this,” FitzGerald said. “It has been a tremendous boost to our business. It is a money-making proposition. We have a lot more people calling us with this problem.
“It is affecting so many different kinds of plants. Usually you will get a bug that is affecting only one kind of plant. It is getting out of hand,” he said.
Tomasello treats larger trees such as palm trees with injections of insecticide at a cost of $1 per inch of circumference. A 40-inch tree would cost $40 to inject, a method that starts to work within 24 hours. The minimum charge per visit is $75. A palm also can be treated with a chemical root drench, which kills the white flies after a few weeks, FitzGerald said.
Pool maintenance companies are also experiencing an increase in customer calls. Swimming pools are turning green as whiteflies and their excretions deplete the chlorine. People unaware of the whiteflies are blaming their pool companies.
“The honeydew leaves a huge white mark all around the pool,” said Steve Adler, owner of Pool Guys of Palm Beach, which has 600 customers from Boca Raton to Jupiter. “It is a nasty, weird sticking substance. It goes into the filter and clogs it. If you don’t have the proper circulation in the pool, it will cloud and could turn green.
“It took us a while to figure out what was going on. It was not public knowledge that the whiteflies were causing these problems. In April and May it hit us really hard in Manalapan,” Adler said. “We started checking for leaks and different sources of problems, then we finally caught on. We talked with other pool companies.
“If the homeowner won’t take care of the problem, we can’t keep up,” Adler said. “We dropped customers who would not take care of it, but almost everybody did.”
Property owner who are having their landscapes treated face enormous and continuing costs. They worry about re-infestations from untreated neighboring properties.
“The most distressing part is the fact that I just had someone out yesterday to give me a quote. I can have them spray and do arbor jets. Not all the neighbors will do that,” Collier said. “I do feel like the city should step up to the plate and at least treat the swales.”
Rugose spiraling whitefly
Scientific name: aleurodicus rugioperculatus
First detected in the U.S. in Miami-Dade County on a gumbo limbo tree on March 11, 2009, it is believed to have originated in Central America.
Plant damage: Whiteflies suck nutrients from plants. They cause the plant to wilt, drop leaves and yellow. Most noticeable are an abundance of the white, waxy material covering the leaves and also excessive sooty mold. Whiteflies produce ‘honeydew,’ a sugary substance which causes the growth of sooty mold.
Long-term effects: Not yet known. However, whiteflies cause plant decline, defoliation and branch dieback.
Whiteflies do not typically kill large, healthy trees, shrubs and palms. However it is unknown what the effect will be of continuous whitefly infestations. Untreated plants covered in sooty mold will decline.
Management: For small plants and early stages of infestation, thoroughly wash plants with a strong stream of water. Follow up with insecticidal soap or horticultural oil sprayed once a week. Repeat as needed.
For larger plants, ornamental trees, heavily infested plants: Wash off plants. Consider using a systemic insecticide, labeled for whitefly control in landscapes, that can be applied to the soil as a drench, granule or tablet. Systemics may take several weeks to be effective for large trees but can last for nine to 12 months.
Hire a professional to treat large trees and shrubs that cannot be hosed off, or if your treatments are not effective.
Source: University of Florida IFAS Extension