420 Journal of Agriculture, Victoria. [10 Jri.Y, 191S. 



I^OTES ON VINE BLACK SPOT OR ANTHRACXOSE. 



By F. de Castella, Government Viticulturist, arid C. C. BrittlehanTc, 

 Government Pathologist. 



The abnormal rainfall of the last two seasons is responsible for a 

 quite unusual prevalence of fungus pests of all kinds, among which 

 Vine Black Spot has made itself very conspicuous. Injury of a 

 disastrous nature has been wrought in many districts where, for over 

 twenty years previously, the fungus was practically unknown. Con- 

 sternation has naturally been caused in many quarters, as a result of 

 which several misleading ideas have gained currency. It has, for 

 example, been stated that the recent outbreak was caused by a new 

 fungus, which developed in the soil, whence it found its way into the 

 sap of the vine, &c. Such fears are quite groundless ; the fungus with 

 which we have to deal is as old as civilization, having been well known 

 in ancient Greece and Rome. The disease and its treatment were dealt 

 with by the present writers at some length in these columns just a year 

 ago; the notes which follow are intended to be supplementary to that 

 article, a reprint of which is obtainable on application. 



The following paragraph from it may be here quoted : — 



As regards the future : Given a return to normal spring weather, 



unfavorable to its spread, the disease will no doubt revert to the 



unimportant position it has so long occupied. But if we fail to 



get a dry spring, and if no preventive steps are taken, grave damage 



is not only probable, but certain. A repetition of last year's 



weather might easily lead, in the absence of treatment, to a real 



disaster to growers of Sultanas and other susceptible varieties, 



owing to the abundance of the fungus in its hibernating or resting 



stages, in which it awaits the return of spring to renew its activity. 



The worst fears then expressed have, unfortunately, been only too 



fully realized; not only was the wet weather of 1916-17 rej)eated, but 



the 1917-18 season proved very much wetter, so much so, that the fungus 



re-appeared with a virulence hitherto unknown in this State. In many 



sultana vineyards, especially in those which had suffered to some extent 



during the previous season, the visitation was altogether disastrous, 



resulting, in many cases, to entire destruction of the 1918 crop, arid 



such severe injury to pruning wood, that little fruit can be expected in 



1919. Other varieties have suffered in varying degree. 



Even in new districts, where it was ditficult, twelve months ago, to 

 find scars for demonstration purposes, the disease has now obtained a 

 considerable foothold. Though a slow-spreading fungus as compared 

 with Downy Mildew or Oidium, it has been steadily disseminated 

 through the agency of birds, insects, &c., facilitated by the extra- 

 ordinarily suitable weather conditions, until it is now sufficiently 

 plentiful to constitute a menace of extreme gravity to growers of all 

 vine varieties susceptible to the disease. 



In view of these facts, very thorough treatment cannot be too 

 emphatically urged. We may briefly recall that, in order to be 

 thoroughly reliable, treatment must be twofold; it must consist of — 



(a) The winter swah, designed to destroy, in the greatest 

 measure possible, the hibernating or wintering forms of 

 the fungus. 



