These tiny white insect are very prolific and usually appear in great numbers. The Whitefly extracts plant juices from the leaves of tomatoes, cucumbers, lettuce, and many other garden plants, causing them to yellow and wilt.

Like aphids, whiteflies secrete a sticky, sugary substance called honeydew on leaf surfaces; a sooty black fungus may grow on the honeydew.

Adult white flies lay their eggs on leaf undersides. The larvae, which look like flat, oval, semitransparent scales, feed on leaf veins before pupating. Whiteflies rarely cause severe problems in the garden. They are much more common in greenhouse environments.