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Rambler " indicates that it could readily be infected, and 

 this proves to be the case with this variety. The greater 

 susceptibility of Roses, and of plants in general, to disease 

 when grown under glass, than when the same kind 

 of plant is grown in the open, depends almost entirely on 

 the relative " softness " of the foliage and shoots. Early 

 morning ventilation, which is too frequently neglected, is 

 the best corrective for this condition of things. 



A damp, warm " muggy season " causes the foliage 

 of plants growing in the open to remain " soft," and 

 highly susceptible to disease. The reason of this is the 

 roots are constantly taking up water which cannot 

 readily escape from the leaves on account of the amount 

 of moisture present in the air, consequently the cells of 

 the leaf are always distended with watery cell-sap, a 

 condition of things which favours, in the first instance, 

 the rapid germination of fungus spores that alight on the 

 surface of the leaves, and secondly, the easy entrance of 

 the germ-tubes of such spores into the interior of the 

 leaves. 



An exceptionally rainy season is unfavourable for the 

 "development of mildew and other fungus diseases, be- 

 cause rain washes the spores to the ground almost as 

 fast as they are produced, also those spores that do 

 alight on the leaves are frequently washed off before they 

 have time to germinate and enter the tissues of the leaf. 

 Another factor of importance is the comparative absence 

 of insects which play an important part in conveying 

 spores of fungi from infected to healthy bushes. 



Mildew is present throughout the season every year 

 in greater or less abundance, but as a rule there are two 



