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to disturb the subsoil or mix with it the top soil. A lesser 

 thickness of non-calcareous soil, resting on a calcareous 

 subsoil, is sometimes sufficient in moist regions, where there 

 is no drought, or a drought of short duration, allowing the 

 roots to live on the surface in the non-calcareous soil. It is 

 the best grafting-stock to choose for the red, pebbly, or 

 slightly calcareous soils, when the soil is at least 50 cm. 

 (16 inches) in depth, and rich, mellow, and sound. These 

 various kinds of soils are frequently met in French viticul- 

 tural regions. Spraying the vines with sulphate of iron 

 (method of Rassiguier) may serve to increase the area for 

 the culture of V. Riparia in f fairly calcareous soils. 



V. RUBRA. 



The V. Rubra is a very rare species in America; it is 

 limited to three or four points on the banks of the Missis- 

 sippi and Merrimac Rivers, in the sandy, 

 very rich, fresh, and moist allu vials, where 

 it only acquires a small development. It 

 exists in a few rare collections, and remains 

 there. The V. Rubra has, however, a very Fig. 55- Seed of 

 great resistance to phylloxera, according to 

 Millardet, but its constant feeble vigour renders it valueless 

 for reconstitution ; it only has a certain value as far as 

 hvbridization is concerned. 



