In the absence of natural enemies, a few individuals can become thousands in a very short period of time. Some whiteflies, such as the silverleaf whitefly and the greenhouse whitefly, attack a very large number of plants. Silverleaf whitefly for example, has over 500 hosts. Other whiteflies are restricted on their hosts and attack only a few plants. Host lists for the more common whiteflies are available under the description of each whitefly listed above.
Whiteflies are often very difficult to control.
Their location on the underside of the leaf makes it difficult to deliver insecticides to the site where they are found. Also, whiteflies rapidly develop resistance to the insecticides used against them. Statewide Integrated Pest Management Project's Pest Management Guidelines or Fact Sheets . Remember, insecticides can be dangerous. If you chose to use an insecticide, read and follow the label directions carefully.