564 PROCEEDINGS OF SECTION G2. 



of the fungus. I believe that these apparent anomahes could be 

 explained if we had a record tracing of the bush land showing the 

 location of the biggest trees, or if we could locate the position of 

 roots left behind in the clearing and their nearness to the layer 

 within which the vine roots extend, that is, if we could locate the 

 original foci of the Dematophora and allied fungi. 



The Rupestris Martin, the Mourvedre x Rupestris No. 1202, 

 the cordifolia x riparia — Rupestris No. 106*^, the Rupestris du Lot, 

 the Aramon x Rupestris Ganzin No. 1, the two Riparia x Rupestris 

 Couderc, and the Riparia x Rupestris Millardet are affected in the 

 order in which I named them. It goes without saying that I am 

 speaking of my experience at the above mentioned State Institution, 

 because in other countries, in France for instance, the Rupestris 

 du Lot, which is one of the most popular Phylloxera resistant stocks, 

 is found to be very sensitive to white rot. 



Five years ago the block of Rupestris Metallica, which first 

 showed to be affected, was uprooted, and this sort was not missed, 

 because experiments here and in Europe proved it to be a stock 

 inferior to the Rupestris du Lot on account of its failing vigor in 

 rather dry climates, after a few years of good vigorous growth. 

 Incidentally I might mention that the Rupestris Metallica had 

 first been imported into Cape Colony, hence it was known in 

 British vinegrowing communities as the Cape Rupestris. 



The block formerly occupied by it was cropped with wheat, as 

 cereals are the only plants that are not affected by white rot. Last 

 year after draining that block through the hollow portion of it, the 

 hollow portion was filled with surface soil taken from the adjoining 

 paddock where the ground is a sandy loam. Last winter between 

 six and seven hundreds of Riparia Gloiie de Montpellier were planted. 

 In the meantime I endeavoured to check the " pourridie " in the 

 other blocks. 



A complete drainage of the whole area under vines was con- 

 sidered a rather expensive undertaking in view of the lay of the 

 ground ; therefore I had to resort to the direct application to the 

 vines of such substances as are generally admitted to have some 

 effect in checking the spreading of the fungus. Five years ago 

 bisulphide of carbon was injected at the rate of one ounce per vine, 

 divided in five partial injections made within 6" to 8" from the 

 stem. 



The fumes of bisulphide of carbon applied in the proportion 

 above-mentioned will kill the mycelium living externally, that is, 

 during the first stage of the infection. Such dose, however, could 

 be hardly sufficient to extinguish the old foci of infection represented 

 by the roots of the once existing trees. Repeated and stronger 

 doses would be necessary, but then the vines themselves would 

 suffer before the fungi on the rotting timber were reached. I came 

 to the conclusion then that a modus vivendi was the only success I 



