214 



J ourTud of Agriculture, Victoria. [10 April, 1916. 



should be controlled by internal poisoning, and the latter by contact 

 sprays. 



Woolly Aphis, or American Blight. 



The woolly aphis, or American blight, is one of the most troublesome 

 pests that apple-growers in Victoria have to contend with. It is peculiar 

 in its habits, as it attacks only certain varieties of apples — immune 

 varieties being the Winter Majetin, Northern Spy, Perfection, Paradise, 

 and a few others. The supposed reason of this is, that they contain 

 more carbonate of lime than those attacked by the aphis. It is advisable, 

 therefore, that orchardists should have their trees worked on blight- 

 proof stocks, otherwise the aphis will attack the roots in such a manner 

 as to render the eradication of 

 the pest impossible. All in- 

 fested trees should be removed, 

 as it is impossible to per- 

 manently cure them. The 

 aphides secrete a white, woolly 

 substance, which gives them 

 their characteristic appearance ; 

 they attack the trunk and 

 limbs wherever they have been 

 wounded or scratched. Almost 

 all parts of the tree are 

 attacked, and knots and 

 aborted growths are caused. 

 The roots attacked develop 

 great lumps many times the 

 thickness of ordinary roots, 

 and the trees are considerably 

 injured thereby. The root- 

 infesting form can be kept in 

 check by the use of m an u rial 

 insecticide or tobacco dust 

 worked into the soil. During 

 the winter, or in late autumn, 

 spraying the trees with red oil, 

 kero&ene emulsion, lime and 

 sulphur, or fluid insecticide 

 has given good results. Spray- 

 ing should be done after 

 pruning, and when the trees 

 are bare of leaves. Of course, 



spraying could be done with advantage at all times, except with the 

 oils. 



The Codlin Moth. 



This moth, originally a native of Europe, has spread over the whole 

 world, and there are now few countries where apples, pears, and apricots 

 are grown in which this destructive pest is unknown. The female moth 

 places her eggs, as a rule, on the sides of the fruit and leaves. Tlie 

 eggs are thin, transparent bodies, resembling a fish scale. Only one 

 egg is placed on each apple, but as each moth lays over 100 eggs, we 

 may judge the amount of damage done in an orchard. As soon as the 



Fig. 2. — Codlin Moth (Cydia pomotiella). 



