THE VEGETABLE GARDEN 205 



during the winter or before the buds open in the spring. 

 Its chief use is to destroy scale insects on fruit trees. 



Tobacco dust. For aphis and flea beetles, place a 

 small quantity in a coarse cloth and dust it on leaves 

 when they are damp ; for insects that injure the roots 

 and stalks, scatter it on the ground around the stems. 



PLANT DISEASES 



Fungi. Both the leaves and the fruit of many plants 

 are attacked by fungi, such as mildew, blight, rust, and 

 black rot. The fungi penetrate the interior of the 

 tissues, so that spraying after the parts are infested 

 is of little value. 



Bordeaux mixture. Bordeaux mixture may be ob- 

 tained either in a dry or in a liquid form, ready for 

 use by simply adding water, or it ' may be prepared 

 by the following formula, which is known as the 

 " standard Bordeaux mixture " : Copper sulfate, six 

 pounds ; stone lime, four pounds ; water, fifty gallons. 

 Place the copper sulfate in a coarse cloth and suspend 

 it in an earthen or wooden vessel containing one gallon 

 of water for each pound of the copper salt. Slake the 

 lime and add one gallon of water for each pound of 

 lime. The stock solutions may be kept separate and 

 mixed as needed. Before mixing add water enough to 

 make twenty-five gallons of each solution. Keep well 

 stirred while mixing. The strong solutions must not 

 be poured together. 



