570 Journal of Agriculture, Victoria. | 10 Sept., 1918. 



On 17th April, the fungus was found to be widespread throughout the Nyah 

 district, as well as at Swan Hill, Tresco, and Cohuna; at the last-named place it 

 was by no means plentiful. 



Contamination was plentiful throughout the metropolitan area late in the 

 autumn. 



Mildura was visited and inspected on 18th February and 1st May, but 

 several days' careful examination failed to reveal any trace of the fungus; it has 

 either not reached so far, or, if present, has spread so little as to escape 

 discovery. 



It will be seen that the disease spread in one brief season from the 

 Rutherglen district to parts a couple of hundred miles distant. In most 

 of the above localities severe damage was not caused, mainly owing to 

 the first appearance of the disease being too late to permit bunch infec- 

 tion, but premature fall of the leaves was in many cases responsible for 

 a marked diminution in the sugar content of the grapes. 



The efficacy of spraying was strikingly demonstrated at one of the 

 large Rutherglen vineyards, portion of which was sprayed in October, 

 1917, 95 per cent, of the grapes being saved thereby, whilst the un- 

 treated portion lost almost the entire crop. 



In vineyards attacked late, at Sunbury and Whittlesea, where spray- 

 ing was carried out early in February, the foliage suifered little, and 

 the grapes ripened. Unsprayed control plots in the same vineyards lost 

 all their leaves, the fruit ripening very unsatisfactorily in consequence, 

 though it was only slightly affected by brown rot.* In these districts, 

 mildew only appeared after Christmas; earlier spraying to combat bunch 

 mildew was thus unnecessary. 



In New South Wales, serious loss was confined to the Murray vine- 

 yards across the river from Rutherglen and Wodonga, where the fungus 

 appeared shortly after its first discovery in Rutherglen (January, 1917). 

 During the 1917-18 summer, however, it appeared at such widely 

 distant places as Yanco, Mirrool, and the Hunter River district; at 

 these, owing to the lateness of its first appearance, the vines escaped 

 bunch mildew, and the yield suifered little. The fungus has not yet 

 been found in South Australia, Western Australia, or Queensland. 



As Regards the Future. 



Forewarned by last season's disaster, North-Eastern vine-growers 

 are no longer in doubt as to the evil potentialities of the new disease. 

 Outfits and materials have already been secured for the indispensable 

 spraying campaign of the coming spring. It is to be feared, however, 

 that in more recently invaded districts, where only slight damage re- 

 sulted last vintage, the peril is less thoroughly realized. Here the 

 situation is exactly similar to-day to what it was at Riitherglen a year 

 ago. To growers in all districts where the fungus has yet appeared, the 

 following warning must be emphatically urged, that, given two contin- 

 gencies, — (a) similar weather conditions to last year; and (b) absence 

 of preventive spraying — no grapes will he vintaged. Even districts 

 apparently as yet unvisited, such as Mildura, should likewise take 

 warning. 



Treatment for the prevention of mildew (cure is impossible) was 

 dealt with in these columns nearly a year ago.+ 



* By brown rot is understood t-lie form of the disease when the berries are attaclced when more than 

 half their full size, as distinguislied from grey rot or bunch mildew, in which case infection takes place 

 before or shortly after blossoming. 



t November, 1917. A reprint of this article will be I'ostrd on application. 



