Life cycle: Citrus leafminer, Phyllocnistis citrella, is a tiny light-colored moth that mates, deposits eggs on young citrus flush, the eggs hatch into larvae that molt 5 times and the larvae pupate in the edge of a leaf. For more information on this insect and the closely related citrus peelminer see ANR publication 8321 Citrus Leafminer and Citrus Peelminer.
Host plants: All varieties of citrus.
Damage: Citrus leafminer larvae can only attack young flush, mining the leaves and causing them to curl and twist. This type of damage significantly slows the growth of young trees in nurseries or new plantings for the first 3 years. Mature trees are generally unaffected by this type of leaf damage. In areas of the world that have bacterial citrus canker, leafminer damage can increase the incidence of the disease because it creates openings for the disease. Citrus canker is not currently found in California.
Distribution: Citrus leafminer is a worldwide pest. It arrived in southern California from Mexico in 2000 and it now infests citrus throughout California