Young larvae usually contain their feeding to the undersides of a leaf. Later instar larvae chew large irregular holes in the wrapper leaves, eat into the outer layers of the head at the base, or feed in the center of the plant that may contaminate the marketed product. Masses of greenish to brown pelleted excrement can be found in the angles of the leaves.

Under good growing conditions, plants can withstand at least moderate defoliation before any reduction in yield occurs. Seedlings may be damaged, but most losses are due to damage to marketed parts of the plant.

Index of Crops

Select this link to browse the damage to each crop by its pests.

Index of Insect Pests

Select this link to browse the insect pests arranged alphabetically with links to their descriptions and life cycle information and the crops they affect.