SPRAYING

Wairarapa Times-Age, 30 October 1940, Page 9

SPRAYING

SHOULD BE THOROUGH. Derris insecticides have found much favour among practical gardeners because they are non-poisonous to animals and to humans, but in addition are very effective in controlling insect pests. The use of Derris as an insecticide is not a new idea by any means, one firm having used it as a basis for an insecticide for many years. Research work upon insect pest control has now reached an advanced stage, and the workers find that certain insecticidal materials give better control over some pests than over others. The main materials in general use are lead arsenate, nicotine, Derris and Pyrethrum, each of which has its distinct use in horticulture and gives maximum control with certain pests. Derris insecticides are subdivided into two groups —washes and dusts. The former is Derris powder, with a suitable spreader added to ensure that when the solution is used it will run into the crevices of the plants sprayed. All contact washes fail to give good control unless they hit the pest; thus if good control is desired the fluid must run into all plant crevices, so that creatures which are sheltering in such crevices are hit. Many fail with insecticides because they fail to apply the solution with sufficient force to make it penetrate ihto all portions of the sprayed plants, and the reputation of many fine insecticides is ruined because of inefficient spraying. Any good firm supplying a Derris insecticide can be relied upon to produce a good article that will kill the creatures stated. However, the various firms do not spray the plants, and any failure which results is due undoubtedly to bad spraying and not to bad washes.

Dusting powders containing Derris are gaining ground each year because the work involved is lighter and the time taken in application is less. It does not take long to dust a large patch of plants, whereas if a wet spray has to be made up and applied much more time is taken up. Busy people will appreciate these points and will use dusts on all pests that are controlled thereby.

The time is now approaching when insect pests begin their season’s activities, and green fly is at work on roses. Good control of insect pests can only be obtained if insecticides are used at the right time. Please do not wait until the pest has spoiled the crop. Get to work and prevent the damage, instead of merely killing the insects: after damage is done. The following pests are killed, or damage is prevented, by Derris washes and dusts: All aphides, apple sucker, capsid bug, caterpillars of all types, cabbage “white fly,” turnip flea beetle, raspberry and loganberry bettie, apple blossom weevil, tortrix caterpillar on roses and fruit, red spider and several mushroom pests.