1 6 GARDEN FARMING 



crystal blue stone (copper sulphate) in 10 gallons of water. In 

 another vessel, preferably wood, dissolve or slake 4 pounds of 

 freshly burned stone lime, using the same quantity of water as in 

 the former case. Dilute these solutions to 25 gallons each and draw 

 equal quantities of them into a third tank, keeping them agitated 

 as they flow into the third tank. The third tank may be the barrel 

 or receptacle to which the spray pump is attached, but in the pas- 

 sage of the liquid from the two receptacles first mentioned to the 

 third one, they should pass through a fine brass wire screen or 

 gauze which has a mesh about the same size as the orifice in the 

 nozzle to be used. These two solutions should not be mixed until 

 immediately before using them upon the plants. Stock solutions of 

 copper sulphate and lime, however, may be made and kept indefi- 

 nitely, so long as they are not mixed. This solution, as will be noted 

 from the above statement, consists of 4 pounds of copper sulphate 

 and 4 pounds of lime diluted with 50 gallons of water. This is 

 the standard Bordeaux mixture, which is used for the treatment of 

 cucumber blight and mildew, the potato blight, and other similar 

 diseases of fruit and forest trees. 



Ammoniacal carbonate of copper. This is another standard 

 fungicide, but is less used than Bordeaux mixture because of its 

 great cost and the increased danger of injury from its application. 

 It is made as follows : Place 3 ounces of carbonate of copper in a 

 large glass receptacle, preferably a bottle, and to it add I quart of 

 ammonia (strength 22 degrees Baume). After the ammonia has been 

 added, stir until the copper carbonate is dissolved. This makes a stock 

 solution which, when needed, should be diluted to 25 or 30 gallons 

 in order to make it the proper strength for use upon tender plants. 



Corrosive sublimate. A solution made by adding 2 ounces of 

 corrosive sublimate to 16 gallons of water was formerly used 

 extensively for treating potatoes for potato scab. This is exceed- 

 ingly poisonous and dangerous to use and should never be left 

 where human beings or domestic animals can gain access to it. 

 Seed potatoes treated in this solution for an hour and a half before 

 planting will be very effectively guarded against the potato scab. 



Formalin. Another preventive of potato scab is prepared by 

 adding i pound (i pint) of formalin to 30 gallons of water. Soak 

 the seed potatoes in the liquid for about 2 hours. 



