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damp clayey or marly soils with an impermeable subsoil. 

 This fungus growth soon gains the roots of vines, developing 

 on them, and occasioning a disease known as pourridie. The 

 effects of this disease are as disastrous as those of phylloxera, 

 for it finally results, in soils favorable to its development, in 

 the death of the vine attacked. It accounts in a measure for 

 the small yield of Victorian as compared with reconstituted 

 deeply-cultivated European vineyards. As we have already 

 remarked, no specific remedy or treatment for it is 

 known. Probably many vine-growers are familiar with 

 this disease, as its white mycelium filaments are easily 

 detected by the eye, and are readily distinguishable by their 

 decided mushroom odour. It exists in a more or less acute 

 form in almost all the vine-growing districts of Victoria. 

 Its appearance can only be attributed to excess of water in 

 the soil, together with old decaying roots in the subsoil. 

 This has been very clearly proved by investigations made by 

 Rochemache * in connexion with the cause of failures in 

 vineyards planted in cleared ground, trenched to a depth of 

 16 inches ; the trenching had not been deep enough to 

 remove all roots, which, consequently, acted as sources of 

 the fungi from which the contagion originated, and, in 

 conjunction with stagnant water, formed veritable hot-beds 

 of infection by pourridie. 



To sum up, it is an essential condition, if we desire to 

 insure permanence and success with American stocks, to 

 disturb the soil deeply, for the following reasons : 



1st. To enable their root system to expand freely, in 

 order to assure the stock developing at the same 

 rate as the scion, and, consequently, success in 

 grafting and profitable yield. 



2nd. To allow access of air to the subsoil, chemically 

 essential to the elaboration of the substances 

 necessary for the nutrition of vines. 



* Revm de Viticulture, 1899. 



