li. Of the MildeiCc' 



Tliis disease does not, in the least, resemble the mildew of wheat, it 

 should rather be termed a palsy of the vitality of the plant, which, 

 in fact, is the name given it in several places. It is caused by an un- 

 reraittincr excess of moisture, damp, or humidity around the roots, 

 or kept up around the plant by evaporation ;, it shows itself by the 

 diluted vigour of the sap, which runs all to wood: the stems are 

 blackish and dry to the pith. It generally strikes newly planted slips 

 that are set out in an improper situation. 



T. Of Cah!:a-s. 



Cankers often happen to the branches ; tiiey may oiigniate in souie 

 internal cause not yet observed or understood ; but they can generally 

 be traced to a stroke of the sun after a frost, a hard bruise, or the 

 touch of a heap of stable dung. In unfavourable seasons the rapidity 

 is astonishing, with which this disease will run through its diife- 

 rent stages ; but usually its progress is but slow. The remedy is ti > 

 run a knife above and below the part, around the stem, cutting- 

 through the bark and pellicle to tlie wood, or binding the part tightly 

 with a string. 



bi. Diseases of the Leaves. 

 The Blast, the Rust, and the Yelloios. 



The Blast takes place in the summer, owing to hot South winds af- 

 ter a fog. It appears suddenly ; the leaves take a red hue and two 

 days after, fall off. The grapes wrinkle and dry up. The vine-dres- 

 sers, near Paris, call it tlie rougeau, the red plague. There is ano- 

 ther kind that is rarely dangerous: it is attributed to a hot sunshine 

 after rain, the rays passing through the drops that hang up ^n the plant 

 as through burning lenses. It gives the leaves a speckled appearance, 

 marbling them with large and small wliite spots. 



The Rust is owing to a parasite fungus, the EriruEus of the vine ; it 

 forms on the lower surface of the leaves, spots of a tawny colour, of 

 irregular size and shape,, and disorganiz-e« the leaf, making it mifit to 

 fulfil its functions 



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