• Worldwide distribution. On members of the brassica family, i.e., cabbage, cauliflower, Chinese cabbage and radish, but also amaranth and eggplant. An important pest.
• Eggs pink, difficult to see, laid singly or in small groups; larvae with pink/brown stripes along sides.
• Young larvae mine leaves, older ones bore into stems and buds; plants die or have multiple heads as the central shoot is killed and side shoots develop.
• Cultural control: inspect nurseries and crops regularly; look for frass and silk; plant far from old plots; weed; use trap crops, e.g., mustards or Chinese cabbage (Bok Choy); destroy trap crop before eggs hatch.
• Chemical control: in household plots, PDPs to safeguard natural enemies (chillies, neem, derris, pyrethrum); in commercial plots, grow under nets; use Bt (Bacillus thurungiensis) sprays against caterpillars when young.

 Cabbage centre grub, cabbage webworm

Hellula undalis. Another species found in Hawaii and warmer parts of Europe, Asia and Africa is known as Helllula rogatalis. At one time, it was thought to be the same as Hellula undalis. It is a moth of the Crambidae.