THE ENEMIES OF THE ROSE 119 



enemies of the Rose this is, as a rule, the most trouble- 

 some to deal with. It appears as a white mould on 

 the foliage, and if not promptly dealt with will quickly 

 spread from one plant to another over the whole col- 

 lection. It occurs at all seasons, but principally in 

 autumn, when, if not checked, it will prevent the 

 plants from flowering as freely as they otherwise 

 would. Flowers of sulphur is a sure preventive, but 

 each attack must be dealt with on its first appearance, 

 and the application repeated until a cure is effected. A 

 very simple way of applying the sulphur is by shaking 

 it lightly over the affected plants by means of a fine 

 muslin bag the first calm evening after the mildew is 

 detected. Although only the upper surface of the 

 leaves are dusted over it will be found in practice 

 that the action of the sun will vaporise the sulphur 

 and cause the surrounding atmosphere to be impreg- 

 nated with it. Syringeing or spraying with the follow- 

 ing liquid will also prove effectual, more especially 

 if the under side of the leaves can be wetted with it. 

 To make this mixture half an ounce of potassium 

 sulphide should be dissolved in a gallon of hot water, 

 which should be well stirred as the sulphide of potas- 

 sium dissolves ; when cold the liquid will be ready 

 for use. Warm days followed by cold nights are 

 the most frequent causes of this pest, also a close, 

 muggy atmosphere. 



Red Rust or Orange Fungus. — This is much more 

 variable than mildew, and in many gardens is seldom 

 if ever seen, while in others, particularly those on 

 hot and dry soils, it is frequently very destructive to 



