A RECENTLY INTRODUCED CABBAGE PEST.

Horowhenua Chronicle, 10 March 1931, Page 8

A RECENTLY INTRODUCED CABBAGE PEST.

PIERIS RAPAE SHOULD BE WATCHED. Thik insect, which recently made its appearance at Napier, Hawke’s Bay, is regarded in some parts of the world as a serious cabbage pest, and at is therefore in the interests of all that every effort should be made to stamp it out. It attacks all vegetables of the cabbage family, riddling the leaves with large holes and rendering edible portions unfit for consumption. So much of the leaf tissue may be devoured that the growth of the plant is seriously checked and it has but little chance of recovery. The adult insect is a white butterfly with three or four black spots on the wings; it measures about five-eighths of an inch in length and has a wing expanse of about two inches. The caterpillars are of an intense leafgreen colour, except for a slender orange stripe down the middle of the back and another broken stripe along each side of the body. In a general way they have a velvety appearance/ due to numerous close-set, short, white and black hairs that form a kind of white bloom over the body. No work has been done in New Zealand on the control of these pests, but they have been carefully studied in the United States, where the following spray is said to be effective against them: Dissolve 31b of laundry or fish oil soap by boiling in several gallons of water, make this up to 50 gallons and add to 21b. of calcium arsenate. The spray is now ready for use and may be applied with safety up to within three or four weeks of harvesting the cabbage.