ACCIDENTS, DISEASES, PARASITES. 187 



also applies to the removal of tendrils remaining attached in 

 winter to the wires of a trellis if the vine was attacked by 

 black-rot the previous summer. The leaves and tendrils 

 should be burnt on the spot. 



Heaps of old canes from diseased vines should not be left 

 near the vineyard, but should be burnt or removed as soon as 

 possible. 



If these different precautions are followed, and if the 

 applications of Bordeaux mixture are made carefully and at 

 the right time, the vineyard should be protected, in most 

 <;ases with four or five successive treatments. 



(E.) CONIOTHYRIUM DlPLODIELLA OR WHITE-ROT. 



When grapes are affected by this disease, some of 

 the parts are covered with greyish-blue stains. These 

 stains increase rapidly in size, and the whole berry is 

 very soon affected. As the disease progresses numerous 

 small blisters, salmon coloured, appear on the surface ; 

 they are formed by the fructification (pycnidici) of 

 the Coniothyrium diplodiella (Phoma diplodiella ; Phoma, 

 Briosii, Sacc.). Soon after the berries dry away and as- 

 sume the aspect of shagreen, resulting from the high 

 relief of the blisters. Similar alterations take place on the 

 peduncle and the pedicles of the grape, and later on, on the 

 berries. Their colour turns a deeper brown, rapidly 

 extending on the whole surrounding tissues, reaching 

 the berries which are first affected at their point of inser- 

 tion with the pedicle. 



The lesions of the peduncle are frequently so deep that 

 they cause the grape to fall to the ground, especially when 

 ^epages with soft stalks, such as the Aramou, are attacked. 

 In any case they cause the grapes or the berries to dry. 

 Certain vineyards planted with Aramon in the alluvial soils 

 of Vidourle, near the Sommieres (Gard), and in the plains 

 of the Ganges (Herault), completely lost their crop ; the 

 whole ground was covered with grapes as if they had been 

 cut purposely. The alteration to the peduncle seems to be 

 the main cause of the damage. 



In two vineyards at Bollene (Vaucluse), and at Landun 

 and Bagnols (Gard), the same lesions were observed on 

 canes. They seem to attack canes which are not yet ligni- 

 fied ; therefore Grenac/ie, which ripens its wood late in 

 the season, is the most affected, while Clairette and Carig- 

 nane are seldom attacked. The disease rarely affects the 



