8 How TO MAKE GRAPE CULTURE PROFITABLE IN CALIFORNIA 



stated, on account of its more penetrating roots takes a quicker start 

 and grows more vigorously. But any vine, which makes vigorous 

 top-growth, will soon exhaust the soil moisture in California, and 

 then if it has not an inherent resistance to dryness, will succumb. 

 My experience with the Rupestris St. George is, that it grows ex- 

 ceedingly well while young, but as soon as it receives a Vinifera 

 top, attains full size and exhausts the soil moisture, it begins to 

 show signs of distress. It may do fairly well on deep, loose, poor, 

 gravelly hillsides in localities with ample rainfall and careful culti- 

 vation, but even on such soils the Champini will grow and pay 

 much better. 



I shall say here that the same cause may prevent the thrifty 

 growth of a vine or effect its death in some other manner; this 

 would be more the case on the poorer soils. For this reason also 

 Viniferas, grafted on Riparia or Rupestris, contrary to French ex- 

 perience, do not bear so well or produce as large grapes in Califor- 

 nia, as they do on their own roots. The fruit and leaves of a vine 

 sunburning badly, can also be traced back to this. It is not caused 

 entirely by the direct rays of the sun, as is supposed by most, but 

 indirectly and principally by the dryness of the soil. Whenever 

 some of the roots become distressed, it affects those grapes and 

 leaves, which are fed by them. The sunburning occurs on rich as 

 well as on dry ground for reasons, which can easily be seen from 

 explanations in other parts of this treatise. It may easily be de- 

 ducted from the above that not much can be expected from the 

 Riparia-Rupestris hybrids. 



One of the principal differences in the characteristics of plants 

 of cold and those of tropical and semi-tropical countries is the great- 

 er or less amount of heat there is required to cause evaporation of 

 moisture through their foliage and so vital activity. Tropical plants 

 transplanted into cold countries would die for want of proper ex- 

 halation of moisture and sap circulation, and cold climate plants 

 transplanted into hot countries would die on account of a too 

 rapid evaporation of moisture through their leaves, but these latter 

 would last much longer under such conditions, if the soil contains 

 plenty of moisture, than if it is deficient in this. We see by this that 

 adaptation to certain climatic and soil conditions rests not only in 

 the roots of a plant but also in its foliage. For this reason top- 

 grafting resistants on non-resistants has been quite effective in sav- 

 ing Viniferas for a number of years ; for the same reason,' grafting 

 non-resistants on resistants has not been a complete success, at 

 least not in certain localities. But as some very fair results have 

 been obtained with grafting stocks like Lenoir, Champini and others 

 without any other precautionary measures, a much better showing 

 can certainly be made in the future, considering our better knowl- 

 edge of the matter. 



