104 MILDEW : HOW TO DESTROY 



to grapple with. As a stagnant atmosphere is favourable to its 

 development, it naturally follows that one of the surest preventives is. 

 air plenty of sweet fresh air and this can be secured to a great 

 extent by proper ventilation, and a judicious use of the heating 

 apparatus to set the air in motion. Where this is not available, a, 

 drier atmosphere should be maintained during the cold, damp weather, 

 avoiding all unnecessary syringing or damping. 



To arrest or destroy the mildew where it has once obtained a footing 

 many and varied means have been recommended and adopted. The 

 most effective indeed, the only truly effective agent is sulphur, or 

 certain compounds of which sulphur forms the major part. It is 

 chiefly in regard to the method of application that the distinction 

 between the various agents is made. Firstly, let it be noted that 

 the sulphur must not be ignited in any way ; that would, to a cer- 

 tainty, not only destroy the mildew, but also the Vines themselves. 

 We have seen Vines so treated and so destroyed. As a preventive, or 

 safeguard, it is not a bad method to give the hot-water pipes not a 

 flue a washing or coating over with the flowers of sulphur mixed 

 with water, or milk, which makes it adhere better, the gentle 

 sulphurous fumes thereby arising being destructive to the mildew. 

 Another remedial measure is to throw sulphur on lumps of fresh 

 slaked lime, which will have a like result. The most effectual and 

 simplest remedy of all, however, is to dust flowers of sulphur all 

 over the Vines. This will, in the course of a few days, destroy it, 

 when the sulphur should be immediately washed off by a forcible 

 syringing with clear rain-water, otherwise the Grapes, being covered 

 with sulphur, would be unfit for use. Many varieties of sulphurators 

 for the application of sulphur have been introduced, one of the 

 simplest being Wood's Sulphurator. 



Various liquid compositions, which are applied with a syringe, have 

 also been introduced, and are effectual in its destruction such as the 

 Gishurst Compound, and others but as these frequently contain a 

 portion of oleaginous matter, their use is not to be recommended. 



Oidium Balsamii (Montague). This mildew is different in its 

 action to that of the Oidium Tucktri, and not nearly so destructive, 

 so far as at present observed. It chiefly exists in the fleshy stalks of 

 the bunches and berries of the Grapes, which become swollen, and so- 

 thickly covered with the mildew as to detract from their value. It 

 only seems to make its appearance as the Grapes are becoming ripe. 

 In the Royal Horticultural Society's Garden, at Chiswick, it has 

 for several years been observed to attack the Gros Colman Grapes in 

 one of the houses. No effectual means has yet been discovered of 

 checking its progress. According to Mr. G. W. Smith, who has 

 described this mildew in the Gardeners' Chronicle, it is identical with 

 the Strawberry mildew. 



American Mildew (Peronospora viticola) is another disease of a, 



