POWDERY MTIvDEW OF GRAPE (Uncinula necator). This mildew 

 is found principally on the leaves of the grape, and in moist situations 

 may do considerable injury. It develops on both sides of the leaf and 

 spreads very rapidly owing to the large number of conidia produced. 



Control. The most successful method of control seems to be the 

 dusting of the leaves with powdered sulphur. The use of self boiled lime- 

 sulphur has also been recomm.ended. 



Of the other common forms, we should like to mention: — 



Uncinula salicis. 



Powdery Mildew of willow and pop- 

 lar, 



Mildew of woody plants, lilac and 

 others. 



Powdery Mildew^ of peas. 



Mildew of Composites, 



Common Mildew of trees. 



Microsphaera alni. 



Erysiphe polygon!. 



Erysiphe cichoracearum. 



Phyllactinia corylea. 



These forms do not often become injurious enough to be considered 

 of very great economic importance in Quebec. 



