134 MANUAL OF MODERN VITICULTURE. 



this accident is not to be feared it. is preferable to substi- 

 tute the cordon-chaintre, which is easier to manage.* 

 However, these methods do not allow cross-ploughing. 



Fig. 115. Chaintre. 



(C.) HEIGHT OF VINES. 



Vines may be classified as follows with regard to their 

 development : Low ; medium ; high. 



Low vines are those in which the shoots start near the 

 soil, and the fruit is consequently a few inches from the 

 surface. These give the richest grapes in saccharine matter 

 on account of the proximity to the soil, which reflects 

 the heat and light directly on them. But the action of 

 radiation, which in summer (by an emission during night of 

 the heat absorbed in excess during the day-time by the soil) 

 heats the plant, results on the contrary in spring in reducing 

 the temperature of the soil and the plant often below 

 freezing point. This lowering of temperature results from 

 the loss of heat taking place from the soil towards the 

 atmosphere during clear nights. Low vines are therefore 

 more subject to the influence of spring frosts. This method 

 can therefore only be adopted in warm climates or on hills ; 

 but it must always be adopted where possible on account 

 of the superior quality of the fruit. High and medium 

 vines in which the shoots start from a certain height above 

 the soil give musts poor in sugar, and they should only 

 be used when the short method cannot be applied. These 

 two last methods are rarely used in the South of France, 



* Culture de la Vigne en chaintre, by A. Vias, instituteur. Paris, librairie agricole de la 

 liaison rustique, 26 rue Jacob. 



