GRAPE VINES SHANKING. 327 



thinly to the upper half of the surface of the pipes. The fumes of sulphur are always 

 attended with risk of rust when the berries are the size of peas or less, and an overdose 

 may so harden the skin as to cause the berries to crack or to colour prematurely, whilst 

 nearly ripe or quite ripe white, tender-skinned grapes become tinged with purple hues 

 and spoiled. Sulphur on hot-water pipes must be used carefully and discriminately. 

 Placing lumps of fresh-burned lime in flower-pots, sprinkling with water and scattering 

 sulphur upon the hot, slaking lime is often as injurious to the vines as destructive of the 

 mildew or other parasites, and the practice is best avoided. 



Other forms of mildew occasionally attack vines. One of these is the Strawberry 

 Blight or mildew, Oidium Balsami, which somewhat resembles 0. Tuckeri, but its 

 conidia are more slender, and the attacks more local. It infests the stems of the bunches 

 and footstalks of the berries, distorts them, and depreciates the value of the grapes. 

 The Oidium succumbs to early and persistent treatment with flowers of sulphur. 



As preventive of parasitic fungi, all dead leaves and prunings should be collected 

 and burned, the surface soil removed, and fresh compost supplied ; the glass, wood, and 

 iron thoroughly cleansed, the structure painted, walls limewashed, the vines washed witli 

 soapy water, and dressed with a fungicide. 



Of late years a disease has attacked the half-grown leaves of young vines and the 

 laterals of old ones in August and early September. It commences at the points of the 

 shoots, causes the leaves to contract, the whole tissue hardens and becomes leather-like, 

 assumes a blackish-brown appearance, growth entirely ceases, and shrinkage occurs in 

 the young shoots. The disease resembles a bad case of rust, and is common to cucumbers 

 and tomatoes late in the season. We have not been able to detect any parasite. The 

 affected parts should be cut off and burned. 



Shanking. This malady causes the withering of the footstalks of the berries and 

 sometimes the stems of the bunches. It generally appears when the grapes show colour, 

 and continues till they are ripe, sometimes afterwards. In bad cases shanking com- 

 mences before the grapes begin colouring. A few berries here and there are found in 

 the bunches of the best-managed vines ; in the worst cases whole branchlets and even 

 entire bunches collapse. Shanked berries are sour and worthless. 



The disease may be traced from a minute brown speck to its final encirclement of 

 the stalk of the berry, or stem of the branchlet or bunch. Sometimes the ring is very 

 narrow, as if formed by the finest wire ligature, in others it is more irregular and 

 broader, and in some cases the whole footstalk or stem is discoloured. The gangrene 



