156 MANUAL OF MODEEN VITICULTURE. 



The damper and lower the soil the more affected the vines 

 will be. Old vines or vines ripening -their wood late and 

 imperfectly suffer most. The same thing applies to vines 

 recently dug. If the vines are not pruned they resist cold 

 better. 



In countries where winter frosts are frequent the stumps 

 are sheltered by earthing up the soil to the level of the 

 arms, or by burying the stump. This is generally suffi- 

 cient to prevent them from getting frosted. These methods 

 are used in the Jura, Rhine, Tokay, and Crimea, and the 

 environs of Pekin. In cold regions, such as Beaujolais, it 

 would be advisable to earth up the vines, especially those 

 grafted, for if the plant is cut down to the level of the soil 

 the graft is lost. The cultivation of vines ripening their 

 wood early and late prtining and ploughing are the only 

 remedies. 



If a great number of plants have to be cut back the 

 whole vineyard must be uprooted ; if a few only have been 

 frosted they should be grafted again or cut level with the 

 soil. But in this case the vine does not give any crop for 

 many years, on account of the great vigour of the shoots 

 born from the old wood which grow wood and no fruit ; 

 grafting, on the contrary, enables the vine to produce fruit 

 straight away. 



(c) Spring frosts. Spring frosts are much more fre- 

 quent, and occur at much shorter intervals, even in warm 

 countries. According to Petit-Lafitte, they occur every nine 

 years in the Gironde. Mares states that they occur every . 

 three years in Languedoc. They are not so injurious as- 

 winter frosts as they do not kill the plant but only affect 

 the crop. 



There are two different spring frosts : black frosts and 

 white frosts. The former result from a general cooling of 

 the atmosphere, the temperature on the ground being much 

 colder than is the case with the latter. They generally 

 occur before the white frosts, at the start of vegetation. 

 When the atmosphere and soil are dry, and the thaw slow 

 and progressive, there is not much harm done ; when, on the 

 contrary, the thaw is rapid the shoots dry and the buds die. 

 These frosts often produce swellings (Fig. 1 38) or excrescences 

 at the base of the spurs or on the roots, known under the 

 name of Broussins. The death of the buds often causes the 

 death of the spurs, and sometimes that of the arms. In this 

 case the effects of frost are felt for many years, and the 

 stumps have to be cut back to get them into shape again. 



