26 



Methods of Control. Apple Aphides can be controlled 

 by spraying, but too frequently this treatment proves in- 

 effective owing to the fact that it has been carried out too 

 late. The most injurious species the Rosy Aphis causes 

 such curling of the leaves that the pests are quite protected, 

 and spraying under these conditions is to all intents and 

 purposes a waste of insecticide. Effective spraying can, how- 

 ever, be carried out: 



(1) By using lime-wash early in the season when the eggs 

 are about to hatch. The normal time to apply this wash is 

 when the leaf -buds are swelling and about to burst, but 

 many growers continue the treatment with good results to 

 within a week or so of the opening of the blossom. The 

 effect of the wash is to prevent some of the eggs from hatch- 

 ing and to kill newly hatched aphides or so hamper their 

 movements that they are unable to establish themselves. In 

 lime- washing, the whole tree must be covered, and specially 

 the twigs and smaller branches. 



(2) By using a contact insecticide (such as nicotine and 

 soap or pyridene and soap) during the period between the 

 opening of the leaf -buds and the bursting of the bloom. 

 Where there is no curling of the leaves, this spray may also 

 be applied soon after the petals have fallen from the blossom. 

 In using all contact insecticides, the application must be very 

 thorough, so that the insecticide penetrates into the half- 

 expanded buds and reaches every insect. The nozzle used 

 should give a rather coarse and powerful spray. 



(3.) By using a contact insecticide such as paraffin emul- 

 sion from the middle to the end of October when the leaves 

 are falling. The aphides are then laying the winter eggs 

 and can be killed by a thorough application of the cheapest 

 aphis wash available. At that period there is no danger to 

 be anticipated from "burning"" the foliage, and a strong 

 paraffin emulsion is probably as good as anything. 



Apart from spraying, the only precaution to be taken is the 

 reduction of ants in the orchard, since it appears that these 

 insects are most active in spreading the Rosy Aphis. "When 

 nests are found powdered naphthalene may be dug into- 

 them. 



FOEMUL^E. 



I. Lime Wash. 



Best Quicklime 10-15 Ib. 



Water 10 gallons. 



Obtain only the best stone quicklime and store carefully to 

 prevent it from air-slaking. Builders' lime, which is often 

 partially air-slaked, should not be used. 



Slake the lime with a little water and then add the 

 remainder of the water, stirring vigorously the whole time. 

 Strain carefully before filling the spraying machine. Keep 

 well agitated throughout the application. 



