South Florida is known as a tourist Mecca. The snow birds flock down here every year, stroll the beaches, enjoy the tropical scenery, soak up some sun, contribute to our local economy and away they go, until next year.
South Florida has another kind of visitor that loves the sun and the beaches, attaches itself to our tropical foliage, makes a mess that it doesn’t clean up, adversely affects our local economy and just won’t seem to go away. In fact, it has invited family members to join it for an extended stay.
What Is a Whitefly?
I’m referring to the rugose “spiraling whitefly”, synonymous with the gumbo limbo whitefly. The first sample of this exotic pest was collected from one of our native gumbo limbo trees about three years ago.
Commonly confused with its cousin, the ficus or fig whitefly (which is only hosted by trees from the genus Ficus), the rugose spiraling whitefly is hosted by at least 60 local trees, palms and shrubs. In addition to the gumbo limbo tree, other common hosts include oak, black olive, schefflera, avocado, mango, coconut palms and Christmas palms.
Symptoms of an Infestation
The signs of infestation can be detected by carefully looking at the undersides of the leaves of trees and the fronds of palms. In most cases, as represented by the common name, a distinct spiraling white substance (their eggs) will be noticeable on the leaf surface. For those who don’t spend their spare time looking up to inspect leaves, it’s usually the sudden appearance of a black, sticky substance apparent on plants, cars, patio decks, lawn furniture or almost anything else under or in close proximity to an infested tree or palm.
All whiteflies excrete a carbohydrate in the form of a clear, sticky substance, commonly referred to as “honey dew”. The sugary residue coats whatever it comes in contact with, followed by the growth of a fungus or mold within the substance, causing it to turn black (aka black sooty mold). The insect itself causes damage in two ways: First by piercing leaves to suck water and vital nutrients from its host and second by releasing the honey dew which coats the leaves, interrupting their function of producing those same vital nutrients. Additionally, the honey dew can attract other damaging insects to the host as well.
What’s the Issue with Whiteflies?
The problem is so prevalent that Miami-Dade County, along with the University Of Florida and other involved agencies, has developed websites dedicated to information about the pest. “As of yet, there are no significant numbers of a natural predator helping to control the infestation,” says Keith Weyrick, a certified pest control operator and the customer service manager at One Two Tree/Pest Free who has spent 30 years in the local lawn and landscape industry.
“This is one of the most active and prolonged episodes of an exotic pest in quite a while.”
During the winter seasons of 2010 and 2011, South Florida experienced enough cooler temperatures to slow the white fly activity, but this most recent winter season was warmer and drier than average so there was no decline in activity. White flies develop rapidly in warmer weather, so now’s the time to contact a professional pest control company that specializes in treating trees, palms and landscaping
A quality and comprehensive program will control the visiting pest and protect the value of your property. Most professionals take a comprehensive and pro-active approach by applying fertilizer at the same time as insecticidal treatment, keeping trees and palms as healthy as possible while undergoing treatment.
There is a short list of insecticides that can be used to help manage infested trees and palms, but figuring out how much and how often to apply has to do with the diameter of an individual tree or palm, as well as its height and canopy dimension. Therefore, it is best left to a professional. Treatments can be applied through several different methods.
Contact spraying, systemic drenching and/or direct trunk injection are all acceptable methods. The latter is the newest method and a result of cutting-edge technology. Although more costly than the other two methods of application, direct injection has almost immediate results and will provide longer protection.
“It was not many years ago that the thought of drilling into a tree’s trunk was considered a harmful thing to do” said Dusty Montiel, spray division manager at One Two Tree/Pest Free.
“Today, a trained professional can drill a hole to a specific depth and install a specialty port for the express purpose of dispensing tree healthcare products. The products immediately enter a tree’s vascular system and are quickly transported to the branches and canopy. In some cases results can be measured in 24 hours.”
As a tree ages its bark grows over the port and no harm is done. Systemic drenches that rely on the roots of a tree to absorb and translocate the insecticide to the upper parts of a tree can take weeks.
“It was not many years ago that the thought of drilling into a tree’s trunk was considered a harmful thing to do”
“Today, a trained professional can drill a hole to a specific depth and install a specialty port for the express purpose of dispensing tree healthcare products. The products immediately enter a tree’s vascular system and are quickly transported to the branches and canopy. In some cases results can be measured in 24 hours.Dusty Montiel, spray division manager at One Two Tree/Pest Free.