438 Journal of Agriculture, Victoria. [10 July, 1916. 



Prevention and Remedies. 

 Hessian bands, similar to those used for codlin moth, have been 

 tried with great success. Spraying the trees with any of the arsenical 

 sprays will also be found of much advantage. 



Gum Emperor Moth. 

 This is one of the finest Victorian moths, and has a wide range over 

 the other States. Its large, beautiful green caterpillars are often to 

 be seen on pepper and eucalyptus trees in our gardens. The eggs, 

 which are like little white or creamy beads, are generally placed on the 

 edges of the leaves, sometimes the edges being lined with them. When 

 hatched, the caterpillars are very dark, almost black-coloured, but by 

 successive moults soon change to the beautiful green tint of the full- 

 grown caterpillars, which has star-like tufts on each segment. The 

 caterpillars often measure 5 inches in length. The cocoons are oval in 

 shape, and measure 1 inch to \\ inch in length, and are very tough. 

 The moths are of a delicate reddish-fawn colour, but variable in both 

 size and colour, often with a pink tint and four eye-like spots or 

 blotches — two on the upper wings and two on the lower wings. Recently, 

 these caterpillars have attacked apple trees and roses. Spray with any 

 of the arsenical sprays. These insects are often destroyed by ichneumons 

 and other hymenopterous insects, wasps, &c., also by parasitic flies. 



{To he continued.) 



COST OF INSECT PESTS. 



" We hardly realize," says an American magazine, " that £50,000,000 

 a year, about £1,000,000 a week, is spent directly or indirectly in trying 

 to check the ravages of the insect pests that prey on the crops. Besides 

 this the pests eat, according to Government estimates, about £160,000,000 

 worth of food annually, which brings their cost up to over £200,000,000 

 a year clear loss. In every State effective war is waged on these pests. 

 Every weapon known to science is employed. But no sooner is a 

 particular pest conquered in one part of the country than it appears in 

 another. Emphasis has been placed in recent years on insect-destroying 

 birds, and these are being protected in all kinds of ways. Laws against 

 the use of bird feathers on hats are part of this protection, and in many 

 States forest areas have been established as bird refuges. Science has 

 also attacked the problem in breeding insects to destroy other insects. 

 The melon aphis, for example, used to cost the growers in one Californian 

 valley £1,000,000 a year. The lady bug, it was found, devoured the 

 aphis. So lady bugs were collected and kept in cold storage. About 

 2,000 lbs. were gathered in certain can^'ons in the Sierras, each pound 

 representing about 25,000 bugs. They bred prodigiously. It was found 

 that 50,000 of them would keep 20 acres of melons free of the aphis 

 and other plant lice. As a result, bumper crops have since been raised. 

 So now scientists are studying the problem of bugs to eat bu2:s, which 

 shall in themselves be harmless to the crop. And thus the battle for 

 the crop goes on yenrlv. ^^^^'^ ri^^-^v before, perhaps, wnth such success 

 or with such genorrl npplicat'.cii." 



