4O AMERICAN VINES. 



in a calcareous soil, and perhaps a little more so than the 

 same stock on its own roots, but certainly less than the stock 

 grafted when growing on its own roots, for the disturbance 

 which occurs directly after grafting does not exist in this 

 case, as it took place when the plant was in the nursery, and 

 for this reason under conditions which attenuated its effect 

 on account of the perfect suitability of the nursery soil to 

 the young plants. This has been noticed by many vine- 

 growers of the Charentes, Gironde, Bourgogne, etc., who 

 observed that vineyards planted out with previously knitted 

 and rooted cuttings never become as yellow as those of the 

 same age grafted when growing. 



Chlorosis and Ploughing. Every one has noticed that in 

 certain soils vines become yellow, especially in spring after 

 deep ploughing. It has also been noticed that in the same 

 vineyard a ploughed part becomes more yellow than another 

 part not ploughed. This fact is very frequently noticed in 

 the Charentes, Corbieres, and Auvergne. What is the 

 reason for this? It is that deep ploughing, when the vine 

 has already commenced to grow, suppresses the roots grow- 

 ing in the surface soil, that is to say, in the least calcareous 

 portions. In addition to the ill effects produced by the 

 suppression of a part of the absorbing organs of the plant, 

 it forces it to live for a certain time and that during the 

 period when chlorosis has the greatest effect with its deep 

 roots penetrating the calcareous layers of soil. Superficial 

 ploughing is, therefore, indicated for soils of this nature. 



We have shown that humidity, compactness, and sourness 

 of soil, if alone or combined do not constitute excellent con- 

 ditions for the development of the vine, but are not a great 

 obstacle to its culture, and that they are not the cause of 

 chlorosis; that drought, lack of light, heat, defective colora- 

 tion of the surface of the soil, aeration, grafting, phylloxera, 

 etc., are not the cause of it either. Carbonate of lime, alone, 

 causes the vine, whether American or European, to turn 

 yellow, and its action is always more pronounced as it is pre- 

 sent in a greater quantity or in a more assimilable form, and 

 may be increased by water, which dissolves it and renders it 

 available to the plant, and by grafting, phylloxera, and deep 

 ploughing. We have shown on the contrary, that it is 

 diminished by artificial drainage, salts of iron, etc. We will 

 indicate, when speaking of culture, the important conse- 

 quences resulting from the above considerations. 



