Look on the underside of leaves to find the immature stages of the whiteflies, which are tiny yellow-green spots. Once the adult has emerged, the spots look whitish or silver.

In home landscapes with small ficus shrubs, as soon as you spot whiteflies, spray the underside of the leaves weekly for several weeks with insecticidal soap. Continue to monitor your ficus plants and re-treat as needed. However, if you have a hedge or large tree, use one of the systemic pesticides applied to the soil that is recommended on this UF website: http://miami-dade.ifas.ufl.edu/. If you don't have access to the Internet, call your local Extension office (Broward 954-370-3725, Miami-Dade 305-248-3311, Monroe 305-292-4501, Palm Beach 561-233-1700). Because pesticide recommendations may change over time, it's best to call or read the online the UF fact sheets to get current information.

Adrian Hunsberger is an entomologist/horticulturist with the UF/IFAS Miami-Dade Extension office. Write to Plant Clinic, 18710 SW 288th St., Homestead, FL 33030; e-mail aghu@ifas.ufl.edu.