267 



The following table, drawn up by Viala, shows the resistance 

 of some of the best known vines : 



COMPARATIVE RESISTANCE TO PHYLLOXERA. 



Cultivated Vines and Hybrids. 



Gloire de Montpellier (Riparia) 18 



Rupestris Martin ... ... 18 



Rupestris Monticola ... ... 18 



Rupestris Metallica ... ... 16 



Solonis 14 



Lenoir ... ... ... ... 12 



Isabella . 5 



Species (Wild Vines). 

 Vitis Rotundifolia (Scuppernong) 19 

 Vitis Rupestris (Rock or Sand 



Grape) 18 



Vitis Riparia (River Bank Grape) 18 



Vitis Berlandieri 17 



Vitis -ZEstivalis (Summer Grape) 16 

 Vitis Labrusca (Fox Grape) .. 5 

 Vitis Calif ornica ... ... ... 4 



Vitis Vinifera (European Grape) 



A readily visible external indication of the degree of resistance 

 to the attacks of the insect is afforded by nodosities and by 

 tuberosities on the roots. The ''nodosity" is a swelling on the 

 tender rootlets of the grape vine, which is caused by the bite of the 

 Phylloxera. All vines attacked by the Phylloxera show more or 

 less these nodosities, which are the result of local irritations. 

 When these nodosities, however, assume a more pronounced 

 appearance, such as deeply-seated cancers, they become " tuberosi- 

 ties," and the more numerous these tuberosities are on the roots of 

 a vine the less resistant it is found to be to the attacks of the 

 Phylloxera. 



To sum up the value of the American resistant vines to use as 

 stock for grafting our European vines on, their degree of resistance is 

 due to the fact 1st, that they are exceptionally luxuriant growers 

 and impart to scion or graft both vigour and strength ; 2nd, that 

 the Phylloxera insects do not increase so rapidly on their roots ; 

 3rd, that the swelling of diseased tissues caused by the bite of the 

 insects form at most only nodosities on the roots, and seldom 

 tuberosities or cankered ulcers, and that these swellings rapidly 

 heal and leave the affected part as healthy as ever, little or no 

 inconvenience being suffered by the vine. 



Some five years ago our Department of Agriculture introduced 

 amongst a collection of valuable grapes some of the best American 

 resistant vines, a description of which is given below. 



VITIS RUPESTRIS (the Rock or Sand Grape). Of the two 

 leading species of resistant vines used to graft on, the Rupestris 

 offers all the characteristics which should make it a favourite in 

 Western Australia. In Europe, where the climate is moist in the 

 summer months, the Riparia is often preferred on account of the 

 readiness with which it takes the graft and the fact that it does not 

 sucker as does the Rupestris. With us, however, the circumstances 

 are not the same. The summer months are dry, and a deep-rooting 

 vine stands a better chance of getting a good hold of the ground 

 than does a shallow-rooted one. 



For soils that are dry, sandy, or gravelly, the Rupestris is 

 therefore the vine to select. Should the ground be moist and 



