25 



dead leaves, and to leaves remaining on bushes that have 

 been infected. If this work is thoroughly done no 

 infection can take place the following season. Winter 

 spores are not formed on the wood. 



In cases where rust has previously existed, the 

 bushes should be sprayed just when the leaves are 

 expanding, with a solution of potassium sulphide. If 

 rust spots appear on the wood the patches should be 

 treated with a solution consisting of equal parts of 

 methylated spirit and water. This may be thoroughly 

 rubbed in with a piece of sponge. 



As previously stated, rust is very common on wild 

 Roses, and if such exist near to a Rose garden preventive 

 spraying should be carried out in the spring, as the 

 spores are liable to be carried from one place to another 

 by wind, insects, birds, &c. 



BLACK SPOT (Actinonema rosae}. 



This disease is confined to the foliage, and as a rule 

 is not much in evidence before mid-summer. It appears 

 under the form of somewhat large black or purplish 

 spots, but varies in appearance depending on the texture 

 of the leaf on which it is growing. The patches are 

 sometimes almost circular in outline, and reach to one 

 quarter of an inch in diameter ; at other times the outline 

 is very irregular, giving the leaf a marbled appearance. 

 The blotches are most distinct on the upper surface 

 of the leaf. Although the patches appear black to the 

 naked eye, if examined with a magnifying glass a very 

 delicate, white, cobweb-like mycelium will be seen 

 covering the patches and radiating towards the margin 

 (see Plate III.). When the leaves are fading the surface 

 of the patches are studded with minute black warts, 

 the fruit of the fungus. 



