18 



general appearance, and like it, is a surface mildew. When it 

 attacks the fruit, the skin of the grape is unable to expand, and 

 bursts. 



Treatment — Flowers of sulphur dusted over the diseased parts 

 effectually disposes of this fungus. 



RATTLES; SHELLING. 



Description— Just as the grapes are ripening, they begin to fall 

 off, and this takes place first at the extremities. 



Treatment — As the chief cause of this disease is defective 

 nutrition, manure should be applied, and especially potash. 



RIPE ROT. 



(Glceosporium fructigenum, Berkl.) 

 Description— The grapes are attacked in the ripening stage. A 



reddish brown spot first appears which gradually spreads over the 



whole grape, then black pimples appear which are not so numerous 



as in Black Rot, but they are broader. 



The colour remains dark purplish brown, and the diseased grapes 



fall to the ground ; whilst in Black Rot, the colour is black, and 



the grapes do not fall off. 



Treatment — If there are only a few vines, the grapes affected 



may be picked off and burnt, but where there are a large number, 



the same treatment should be adopted as for Black Rot. 



Fungicides. 



BORDEAUX MIXTURE. 

 Bordeaux Mixture is best made according to the following 



formula : — 



Copper Sulphate ... 6 pounds 



Unslacked lime ... 4 pounds 



Water ••• 50 gallons 



It requires careful mixing, or the ingredients will not combine 

 properly. Put 25 gallons of water into a barrel. Tie up 6 pounds 

 of copper sulphate into a piece of coarse sack, and hang this by 

 a stick laid across the top of the barrel so as to be just beneath 

 the surface of the water until it has slowly dissolved. 



In another barrel slack 4 pounds of lime very slowly and care- 

 fully, at first only adding about a quart of water at a time, until a 

 perfectly smooth paste free from grit, is obtained. Add water to 

 make the whole 25 gallons, and wait until cool. Now pour both 

 together into a cask holding 50 gallons. The milk of lime should 

 be thoroughly stirred before pouring, and finally the mixture 

 should be well stirred for 4 or 5 minutes with a wooden paddle. 



If not perfect, the mixture is liable to injure the foliage and in 

 order to test this, put the blade of a penknife into the mixture and 

 leave it for I or 2 minutes. If there is any deposit of copper on 

 the blade, showing a brownish colour, it is not safe to use it, and 

 more lime must be added until the knife is not discoloured. 



