59 



Downy Mildew. This DOWNY MILDEW 



fungus is Peronospora viticola Showing Bunch badly effected. 



and as it is exceedingly 

 troublesome to Vine growers 

 in France, it is also com- 

 monly known under the 

 name of French Mildew. 

 T liis fungus makes its 

 appearance in minute white 

 spots, on the undersides of 

 the leaves, warm humid 

 weather being most favour- 

 able for its development. 

 These spots gradually in- 

 crease in size till they cover 

 the greater portion of the 

 leaf surface, and the foliage 

 withers and decays. Reme- 

 dies, Bluestone and Lime 

 applied either as a spray or 

 a powder, is considered to 

 be one of the most effective 

 remedies. It is prepared by 

 mixing ten pounds of blue- 

 stone with six gallons of 

 warm water in one vessel 

 and seventeen pounds of 

 quicklime and three gallons 

 of water in another. When 

 thoroughly dissolved mix 

 together, and if required as 

 a spray add water at the 

 rate of ten gallons to one. 

 If required as a powder the 

 material should be placed in 

 shallow vessels and allowed 

 to dry by evaporation. Another fairly effective remedy is the 

 ordinary Kerosene Emulsion with about three per cent, of carbolic 

 acid and a small proportion of glycerine added. The remedies 

 should be applied as recommended for Anthraciiose. 



Mouldy Root. This disease which is perhaps better known under 

 its French name Pourridie is caused by various species of fungi 

 including Agaricus melleus and Dematophora necatrix the latter being- 

 the most common. It mostly occurs in damp badly drained soils, 

 and is said to be more frequent in land recently taken from forests, 

 according to the experience gained in France, where the disease is 

 very destructive. When Grape Vines are affected by this disease, 

 they quickly lose their vigour, assume an unhealthy appearance, 

 make weakly growth and gradually die away. If the roots are 



