Whiteflies are tiny insects; their wings and bodies are covered in white wax. Whiteflies develop rapidly in warm weather. Large populations can cause excessive leaf drop and even plant loss.
How do I know whiteflies are infesting my plants?
Whiteflies feed on leaf sap and leave drops of honeydew in their wake, which is a medium for the growth of a black fungus called sooty mold. Ants like the honeydew—a sign that plants should be examined for whitefly.
Feeding by the nymphs on the lower leaf surface results in mottling and yellow spots on the upper leaf surface. When a branch on a heavily infested plant is shaken, a cloud of adult whiteflies appears, like a snowstorm that escaped from a snow globe. Under heavy infestations, leaves will defoliate prematurely (pictured right).
What are the most common host plants of whiteflies?
Both Ficus hedges as well as individual trees may be attacked. Most common hosts include Weeping fig, Ficus, and Banyan.
Management and Treatment Options
Whiteflies may be kept in check by parasitic wasps, predatory insects and insectpathogenic fungi.
Systemic products that offer residual control may be applied as soil drench, trunk injection, or basal bark spray; the latter two methods are used with large trees. Systemic products may be applied on a preventive or curative basis. If infestations persist, several applications may be necessary to control the population.