Some Grape Troubles of Western New York. 421 



and green parts cannot be instantly replaced by the roots, on ac- 

 count of the rate of circulation already established, those parts 

 wilt, and when they have dried to a certain point they perish. ' ' 

 In conclusion, apoplexy may be said to be due to a disturbance 

 of the equilibrium existing between the absorption of water by 

 the roots and its evaporation from the leaves. No remedy is as 

 yet known for the trouble. Thorough drainage may lessen its 

 severity in some soils. 



Rougeot appears, from the conditions which cause it and 

 by its general nature, to be allied to apoplexy. Like the latter, 

 it attacks vines in full growth, at the time of the first heated per- 

 iods, and is most serious upon cool, deep soils. Thiebaut de Ber- 

 neaud says* that the disease is produced " during summer, after 

 a cold rain, a storm which causes a sudden fall of temperature, 

 or a fog which is followed by warm southerly winds." Mares 

 describes the disease as follows : " The leaves begin to change, 

 shrivel and lose their suppleness. The parenchyma turns red 

 while the veins remain green, which gives the foliage a very pecu- 

 liar appearance. The berries wilt and the shoots remain yellow. 

 If the trouble increases, the leaves dry entirely and the stems die 

 partially, sometimes only one side being affected, the diseased 

 portion extending from the extremity to the base of the shoot. 

 Such shoots often start a later growth during the latter part of 

 the season. Plants attacked by rougeot do not die, as in the 

 case of apoplexy, but they are severely checked, and several years 

 are necessary to a complete recovery." Drainage should be care- 

 fully attended to, and particular pains taken to prune short, 

 or at least down to sound wood. In extreme cases the plant 

 may be renewed by grafting low upon the trunk of the vine. 



Ascribed Causes of the Shelling of Grapes. — The causes which 

 lead to the shelling of grapes are very obscure. Although the 

 trouble has existed a long time among the vineyards of Chau- 

 tauqua county, there are still numberless theories advanced as to 

 the influences which produce it. Nearly every grower has a 

 theory regarding it, but many confess that the disease is a mystery, 

 and that none of the theories advanced will properly explain its 



*Ibid. p. 469, cited from Nouveau Manuel complet du Vigneron Franfais, 

 p. 186. 



