Dealing with sporadic caterpillar pests in cabbages

They may not always be present in your lands, but you still have to look out for these pests, or risk losing your cabbages

- Bill Kerr

Continuous pests are those nearly always present in your lands, and need regular control. Sporadic pests are migratory, cyclical, or occasional pests that require control once in a while.

Very often, sporadic pests are preyed on effectively by a particular insect. This causes cycles where the parasitoid wasp, or other insect, reduces the pest population to a level where the predator population also drops, as there are not enough pests to feed on. This enables pest numbers to increase again in a see-saw effect.

PLUSIA LOOPER (THYSANOPLUSIA ORICHALCEA) This pest, an example of a semi-looper, is an example of a sporadic cabbage pest. I recall once finding a mature plusia looper feeding on a cabbage. On its back was a small black parasitoid with its ovipositor inserted; the parasitoid was clearly laying eggs into the caterpillar.