A new pest has infested south Florida: the whitefly. These little creatures develop rapidly in warm weather, making Florida an ideal climate. When the weather is warm and natural predators are destroyed or curtailed, whitefly populations can very quickly get out of control, causing severe damage to plant life.
Whiteflies South Florida Basic characteristics
Whiteflies get their name from a white, waxy substance that covers the wings and bodies of adult flies. The adult whitefly is very small – not more than 1/16 of an inch long – and resembles a tiny moth.
The life cycle of the whitefly is roughly one month. The flies lay their eggs on the undersides of leaves, where the eggs then hatch. The whitefly nymphs quickly progress through four nymph “crawler” stages before becoming mature whiteflies.
Whitefly feeding habits
Whiteflies feed by sucking the sap from leaves with needle-like mouths. The flies tap into the phloem (or vascular tissue) of a plant, which is how food is distributed throughout the leaves and stem of a plant. Both whiteflies and their nymphs pose a threat to plant life, as all stages feed on plant juices.
The effects of whiteflies on plant life
As the flies tap into the phloem and drain off the plant’s juices, the leaves dry out, turn yellow, and eventually drop from the plant. Because whiteflies congregate in large numbers, they will effectively drain off the plant’s source of water and nutrients, very quickly damaging (and even killing) the host plant.
In addition to stunting the plants’ growth through sucking sap, whiteflies cause further damage as they leave behind a sticky-sweet honeydew excretion. The honeydew encourages the growth of an ugly sooty black mold on the leaves of plants.
Sooty mold is not only unsightly, it also inhibits the photosynthetic ability of the plant, leaving it unable to produce food. Honeydew also attracts ants that drive off the natural predators of whiteflies.
Plants affected by the whitefly
The whitefly has a wide range of host plants, though different whitefly strains prefer certain plants over others. For example, the sweet potato whitefly doesn’t reproduce well on cabbage, though the silver leaf whitefly does.
In all, over 500 plant species are affected by the whitefly, including major crops like cotton, cucumbers, melons, tomatoes, and squash, as well as ornamental plants like poinsettia, hibiscus, verbena, and lantana. Summer crops or gardens, in particular, are susceptible to massive whitefly populations.
Whitefly Control and prevention
Because whiteflies are so prevalent in south Florida, check your plants daily for any sign of infestation and take action immediately to eliminate the flies when they are found. Check the undersides of leaves for whitefly eggs or larvae, as this is a good indicator of whitefly presence.
If whiteflies are discovered, it’s very important to find a pest control company that specializes in removing whiteflies. Using a broad spectrum insecticide will kill helpful insects as well as the whiteflies, so do be sure to get professional pest control advice before using any insecticide treatment.