CDLTIVATION OF THB GRAPE UNDER GLASS. 157 



Mildew of the vine has been a serious source of loss and dis- 

 appointment. Strictly it is not a disease, but a parasitic, fungoid 

 plant, which, under certain favoring conditions grows upon and 

 derives its sustenance from the tissues of the vine. By its growth 

 the further growth of the vine is arrested, and if sufficiently 

 abundant the crop of fruit is lost, and the vine itself seriously 

 and sometimes fatally injured. It is most Kkely to make its ap- 

 pearance in hot, dry weather, particularly if a draught of air be 

 allowed through the house. By keeping the top ventilators open, 

 and not suffering any draughts, the mildew may be whoUy pre- 

 vented. Little injury need be apprehended from it after the 

 Grapes are once well colored. 



There sometimes forms on the lower surface of the leaves a 

 collection of little green warts. They are caused by a close, 

 warm atmosphere, saturated with moisture, and can be prevented 

 by maintaining a free circulation of air, moderately charged with 

 moisture. 



AiB-ROOTS on the vine are caused either by the atmosphere 

 of the house being kept too moist, or because the border is too 

 cold, or by both these causes acting together. "When the natural 

 roots are in a border that in texture, temperature and moisture 

 is congenial to their growth, and the atmosphere of the vinery 

 what it ought to be, there will be few air-roots. 



As a rule, one pound of grapes to every two superficial feet 

 of glass is a fair crop, yet a sound discretion must be exercised 

 in the amount of crop, which should be proportioned to the vigor 

 of the vines. 



SELECTION OP VINES. 



For a person who does not wish to force early grapes, but 

 confines himself to a single cool grapery, the following selection 

 wiU be found suitable, and at the same time give him a succession : 



5 Black Hamburgh. 



2 Muscat Hamburgh. 



1 Royal Muscadine. 

 12 



