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time more or less affected ; generally the leaves turn brown and curl in 

 places, or all over. Insects or fungi have never been proved to be the 

 real cause of the trouble, the chief reason is to be sought in the condi- 

 tion of the Vine itself. No doubt, the disease is not always due to the 

 same cause. Over-cropping frequently leads to "shanking," so, also, 

 does too early ripening of the wood. Both ot these conditions result in 

 a drain on the food-supplies which the plant has to provide, and will 

 lead to starvation of maturing fruit. Excessive moisture and heat pro- 

 duce conditions favourable to "shanking" if they cause undue forcing 

 of the Yines ; on the other hand, any check due to sudden dryness or 

 cooling will be first seen in the fruit bunches. 



From what we can learn, the soil itself has no direct effect, but a 

 weak root-system due to defects in the air, heat, texture, or moisture of 

 the soil, will not be in a condition to supply the necessary water and 

 food to a fruiting Vine. Excess of nitrogenous substances in the Vine 

 due to over-manuring or to over-cultivation of a rich outside border, 

 easily aggravate " shanking. " It is said by good authorities that 

 "shanking" occurs when the Vine is deficient in potash, and they re- 

 commend this to be supplied in some form as a manure to the soil. 

 Dropping of the Grapes is also a common result of any disease of the 

 foliage, stems, or roots of the Vine. 



A disease on out-door Vines, recently described by French investi- 

 gators under the name "maladie pectique," seems to us very like a form 

 of "shanking." The leaves in the lower parts of the Vines show dis- 

 coloured patches, which become wine-red in dark-fruited varieties, or 

 yellowish in white-fruited. This is followed by withering, curling, and 

 drying up of the leaves ; as this goes on, the blade breaks away at the 

 top of the leaf-stalk. Flowers and young fruit behave in the same way, 

 shrivel, and drop from their stalk. The disease was never seen to cause 

 total loss of a Vine, as it never seemed to spread beyond the lower- 

 branches. No parasites of any kind could be found. The conditions 

 which lead to the disease are sudden changes of climate affecting the 

 soil. The soils most liable to it are light, and of a pebbly or slatey 

 nature. The vine-yards, where it showed most, were subjected to severe 

 drought in 1893, followed early in 1894 by continual rain and a mark- 

 ed fall in temperature of both air and soil. These facts support the 

 view that " shanking " on our indoor Vines is not caused by either 

 fungus or insect, but by conditions arising from soil or climate. 



Blanching. 



" Chlorose " or " blanching," is a disease which has caused much 

 trouble in the south of France. The Vine-leaves lose their deep green 

 shade, then become yellow or completely blanched. The loss of colour 

 generally begins near the margin of the leaf, and spreads inwards 

 between the veins ;the affected parts may or may not become withered. 

 Young green twigs sicken like the leaves, and may dry up. The 

 woody branches are retarded ingrowth, and new leaves given off remain 

 small and blanched. As the malady almost always develops before the 

 flowering period, both flowers and young fruit are stunted and dis- 

 coloured, and probably dry up or fall off. French experience shows 

 that chlorose is worst on very limey calcareous soils. On such soils the 

 Vines sicken in the first year, and gradually lose their vigour ; death 



