Citrus Whitefly

• The citrus whitefly (Dialeurodes citri) is a native of India that now roams various U.S. states and other parts of the globe. The adult whitefly is a small, white insect with four, white wings covered by a white, waxy powder. Sixteen different whitefly species exist. They attach themselves to the underside of a lemon tree leaf and suck large quantities of sap, stunting the growth of both the fruit and the tree.
  
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Whitefly Control

• Citrus whiteflies also secrete honeydew that attracts the sooty mold fungus, a disorder that further saps the lemon tree's energy. Several predators were introduced as biological controls against the whitefly, including parasitic wasps and the ladybird beetle. Cultural control focuses on regular hedging and topping. Chemical control measures also are available against the citrus whitefly and center on the same insecticides as used against citrus scale insects.
  
  

Citrus Blackfly

• The adult citrus blackfly (Aleurocanthus woglumi) claims a dark-gray or black body and is the most injurious citrus pest. Its yellowish-brown eggs are deposited on the underside of lemon leaves and produce crawlers that attach to the leaves and refuse to move until they reach adulthood. Both adults and crawlers feed on leaves and secrete the honeydew that attracts black sooty mold. The blackfly is a whitefly species but is called blackfly because of its body color.
  
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Blackfly Management

• The black sooty mold covering the leaves damages the specimen's ability to conduct photosynthesis, depriving it of energy. This causes a lack of vigor in growth and fruit production. Parasitic wasps are biological control agents against the citrus blackfly, and chemical measures are available. Lemon trees that suffered an infestation of blackflies or whiteflies should be well watered and fertilized helping the tree regain its strength.