CHOICE OF AMERICAN VINES. 



57 



B 



contain a very high percentage of humus. Finally, the 

 presence of clay closely united to lime seems to be a cause 

 of diminution in the dangerous action of carbonate of lime 

 upon American vines. 



Certain soils, such as the blue marls, near Montpellier> 

 grow (owing to the large proportion of clay which they 

 contain) Ri- 

 parias, which 

 do not be- 

 come yellow 

 even grafted. 

 When the 

 sub-soil is at 

 a depth of 

 less than 20 

 inches, it has 

 an action of 

 the same 

 order upon 

 vines. 



The good 

 growth of 

 many Franco- 

 American hy- 

 brids in cal- 

 careous soils 

 and their 

 ready adapta- 

 tion to graft- 

 ing with 

 American 

 vines, which 

 was pointed 

 out by Viala 

 and Ravaz, 

 induced many 



to work in that direction. Millardet, de Grasset, Couderc, 

 Castel, Terras, MalegUe and ourselves at the School of Agri- 

 culture of Montpellier, with many others, have made ex- 

 periments in that direction. We tried by fecundating V. 

 Vinifera with American species, such as the V. Berlandieri 

 and V. Monticola, having already the power of resisting 

 limestone, to obtain graft-bearers adapting themselves easily 

 to such soils. Unfortunately, although in many instances- 



Fig. 22. Bernard's Calcimeter. 



