214 THE ROSE BOOK 



is spoiled by the blotches on the leaves, and the flowers 

 are never at their best once the fungus gets well estab- 

 lished. This disease, Actinonema rosa, is characterised 

 by the presence of large purple or dark brown patches, 

 which appear on the upper surface of the leaves. The 

 mycelium is found, on microscopic examination, to be 

 partly on the outer surface of the leaf, but some of the 

 hyphae, or threads, have penetrated into the tissues to 

 absorb more nourishment from the bush. Small, very 

 dark spots may be noticed on the discoloured areas ; 

 these are the fructification of the fungus, and contain 

 the colourless spores. 



Remedies. — No real cure has yet been found for this 

 fungoid pest, though I have heard of a proprietary fungi- 

 cide called Mo-ernc being used with some success. All 

 leaves which fall from the bush should be carefully 

 gathered and burned whenever they fall, so as to pre- 

 vent, as far as possible, a recurrence of the attack. For 

 a light attack the affected leaves should be removed and 

 the plant sprayed with Bordeaux mixture or liver of 

 sulphur solution. 



Canker. — Some roses are liable to Canker, which, if 

 left unchecked, frequently causes the death of the bush. 

 Bad, corky, warty swellings appear at the place where 

 budding or grafting has been carried out, and often at 

 various places along old, strong shoots. Another type 

 of Canker, however, has made its appearance, and pro- 

 mises to be much more destructive. Some of the rose 

 stems may be noticed swollen and covered with a corky 

 growth, generally near the base of the shoot ; in a bad 



