As I write this article there are a number of Rugose Spiraling Whiteflies flying all over my office. Although I’ve had samples coming across my desk for over a year, I still can’t get over how big these whiteflies are compared to the Ficus and Bemisia – almost three times bigger.
HOSTS. This Whitefly was originally called the Gumbo Limbo Spiraling Whitefly, because we thought it was only going to feed and reproduce on that tree. Unfortunately, we were wrong: the Spiraling Whitefly (now renamed Rugose) has a broad list of hosts, which seems to grow by the day. The preferred hosts are Gumbo Limbo, White Bird of Paradise, Coconut Palm, Black Olive, Live Oak, and others.
LIFECYCLE. The adult lays eggs in a telltale spiral pattern on the undersides of the leaves. As with the other whiteflies, it is the young insects that cause the damage through their feeding activities. The young stages of this insect feed on a plant’s fluids with piercing/sucking mouthparts (which causes stress to the shrub or tree). A secondary problem is that feeding activities produce a sticky substance (called honeydew) which supports the growth of sooty mold and may cause a mess, especially if there are cars, sidewalks, etc., below.
LOCATION. As of now, I’ve seen this spiraling whitefly throughout the entire Palm Beach county. It has also been identified all over Broward and Miami Dade Counties for some time now.
TREATMENT. Systemic insecticides in the neonicotinoid family are very effective against the Rugose Spiraling Whitefly. We’ve seen some great results with basal bark and injection treatments. Horticultural soaps and oils will reduce whitefly populations as well.
MORE INFORMATION. Please see Dr. Catharine Mannion’s factsheet on Rugose Spiraling Whitefly or Rugose Spiraling Whitefly Treatment in the Landscape power point presentation for more detail and for a list of recommended products. Please continue to watch the IFAS Palm Beach County Extension: Environmental Horticulture blog and the Palm Beach County Whitefly Task Force website for updates on everything related to whiteflies.