- Whiteflies have a piercing-sucking mouthpart that they insert into the plant tissue to feed on leaves. Leaves may wilt and drop as a result of feeding damage if populations are high.
- Large quantities of a sweet sugary material known as honeydew are also secreted by the whiteflies. Leaves and fruit often turn black with the growth of sooty mould fungus on the honey dew.
- Lemon trees are the favourite host, but all types of citrus are vulnerable to attack.
- Whiteflies are not usually a problem of citrus in Australia.