112 AMERICAN VINES. 



In Virginia, whence many Riparias were imported, the 

 soils are clay-sandy, rich, of a red colour, mixed with 

 siliceous pebbles. In the north of New York State, the 

 Riparia soils were formed from the decomposition of 

 Devonian schists, and constitute a clay-sandy soil with few 

 pebbles and very rich; in Delaware and Maryland, the 

 Riparias are in the very rich, red, grey, or grey -yellow 

 humiferous sands. On the banks of the Great Lakes they 

 grow in mellow soils which have been formed by the decom- 

 position of hard calcareous rocks, of the Devonian period, 

 which are very fertile, although fairly calcareous. When, 

 exceptionally, the calcareous pebbles are numerous and 

 soft, the Riparias are not found; and if, by chance, a few 

 vines are found in these soils they are poor, yellow, and 

 stunted. The Riparias are very scarce, and affected by 

 chlorosis in their wild x state, in the yellow marls and lime- 

 stones of Kentucky and the environs of Sandusky. 



It is in the soft limestones and yellow or white calcareous 

 marls of diverse formations in France that the Riparias 

 have given most numerous failures. Sometimes they are 

 found green and pretty vigorous in those surroundings when 

 the soil is specially rich, but only while they are not grafted; 

 as soon as they are grafted they get chlorosis, become 

 stunted, and die rapidly. The V. Riparia is less subject to 

 the effect of limestone than the V. Rupestris or V. ^Esti- 

 valis; but in soils where carbonate of lime is very plentiful, 

 even if the soil is rich, it succumbs to chlorosis. In dry, 

 unfertile, but non-calcareous soils, it has only a feeble 

 development, and supports poor grafts, showing, as already 

 said, a great difference in thickness between the stock and 

 the scion. The Riparia is best suited by almost non- 

 calcareous soils, naturally fertile, or enriched by plentiful 

 manuring. Under these conditions, no other grafting-stock 

 is superior to it; the numerous examples of resonstitution 

 which actually exist in France prove this in an indisputable 

 manner. 



The Riparia must therefore, play a principal r61e as an 

 element for reconstitution in the siliceous, clay -siliceous, 

 clay -limestone, silico-limetones, deep, fresh, and fertile soils. 

 When the subsoil is calcareous and hard, but covered with 

 only slightly calcareous soil of 35 to 50 cm. (14 to 16 inches) 

 thick, it succeeds very well, provided the soil has the neces- 

 sary amount of fertility, and if in trenching care be taken not 



