What are whiteflies?
Whiteflies are small winged insects that belong to the same family as aphids, scales and mealybugs, which are a common pests found on our plants, trees and ornamentals in Naples. These insects have piercing, sucking mouth parts which drain nutrients from the plant causing wilting, leaf drop, severe yellowing, and in some cases even death. The University of Florida reports that there are over 75 different species of whitefly found in our state.
What plants are hosts for the whitefly?
In 2009 Spiraling Whitefly began its invasion in Miami-Dade County on the Gumbo Limbo tree. Since that time the insect has also been attacking Black Olive, Live Oak, Calophyllum trees, Coconut palms, Areca palms, and Christmas palms.
What are the identifying symptoms of a whitefly infestation?
The most obvious symptom is a large quantity of waxy white, cottony material and black sooty mold on the leaves or fronds. Essentially, the insect sucks the juices out of the plant, digests them and then secrets a sticky substance called honeydew. The black sooty mold grows on top of the honeydew and in cases where the tree or palm is towering above a house, patio, swimming pool or landscape bed, everything underneath will be covered in black sooty mold. Pool companies frequently get blamed for being unable to keep chlorine at appropriate levels when in fact the pool chemistry imbalance is a result of the whitefly problem going unidentified and massive amounts of honeydew falling into the pool.
What can a homeowner do to control the whitefly?
It is recommended that homeowners hire a certified pest control company specializing in the control of these insects. For smaller plants, contact insecticides like horticultural oil and insecticidal soaps can be used as long as several applications are made. Systemic insecticides provide better control by entering the vascular system of the plant. Systemic insecticides can be applied by injecting them, drenching the plant or by foliar application. The whitefly will die after ingesting the fluids or sap from the plant. For larger palms and trees, a pest control company can inject this systemic insecticide directly into the palm or tree for almost instant control of the insect. Depending on the amount of water in the tree, the whiteflies may begin to fall out of the tree immediately after application.
How often do my plants need to be treated?
It is always recommended that treatments be made twice annually to insure optimum control. Typically systemic insecticides last 10-11 months if applied at a high rate, but applying a lower rate bi-annually will be more beneficial for the plant and the environment. Using systemic injection and drench application methods are safer for beneficial insects as well as the environment. The goal would be to allow desirable insects to thrive and out-compete the whitefly.
Should the plant, palm or tree be trimmed if it is infested?
Leaving as much of the foliage on the plant, tree or palm is always recommended. This will help the plant recover more quickly after treatment. If the plant needs trimming, it is recommended that it be trimmed prior to the insecticide application.
Francis X Kitchener, Jr. is a Principal with Blue Landscape Contracting Group, LLC. in Naples. He is a Certified Pest Control Operator, Certified Arborist and Certified Horticultural Professional. “Frank” and his partner Timothy Felts can be reached at 239-566-2583. Blue Landscape provides maintenance, landscape, irrigation and pest control services (including whitefly treatments) in Collier and Lee Counties.