42 The Horticulturisf s Rule- Book. 



David's powder. — Dissolve 4 pounds of sulphate of copper in the 

 least possible amount of hot water, and slake 16 pounds of 

 lime with the smallest quantity of water required. When 

 the copper solution and slaked lime are completely cooled, 

 mix them together thoroughly ; let the compound dry in the 

 sun, then crush and sift. Apply with a sulphuring-bellows 

 furnished with an outside receptacle for the powder. For 

 downy mildew and black-rot of the grape, mildew and an- 

 thracnose. 



Destroying affected parts. — It is important that all affected parts 

 should be removed and burned, if possible. In the fall all 

 leaves and fruit which have been attacked by fungi should 

 be raked up and burned. Diseased branches should be sev- 

 ered at some distance below the lowest visible point of 

 attack. Fungous diseases often spread rapidly, and prompt 

 action is usually necessary. 



Eau celeste.— 1 (Audoynaud py^ocess). Dissolve 1 pound of sul- 

 phate of copper in 2 gallons of hot water. When com- 

 pletely dissolved and the water has cooled, add 1)4 pints of 

 commercial ammonia (strength 23 degrees Baum6). When 

 ready to use, dilute to 25 gallons. For treatment of downy 

 mildew and black-rot of the grape, anthracnose, and blight 

 and rot of the tomato and potato, and many other diseases. 



2. Dissolve 1 pound of sulphate of copper in 2 gallons of 

 water. In another vessel dissolve 1 pound of carbonate of 

 soda. Mix the two solutions. When chemical reaction has 

 ceased, add 1^4 pints of ammonia, then dilute to 25 gallons. 

 For the same purpose as No. 1, and probably better. 



Orison liquid (Eau Grison) . — Prepared by boiling 3 pounds each of 

 flowers of sulphur and lime in 6 gallons of water until re- 

 duced to 2 gallons. When settled, pour off the clear liquid 

 and bottle it. When used, mix 1 pint of clear liquid in 100 

 parts of water. For mildew and powdery mildew of vines. 



Podeschard's powder.— Dissolve 45 pounds of sulphate of copper 

 in water. When thoroughly dissolved, pour the solution 

 upon 225 pounds of air-slaked lime, which is surrounded by 

 30 pounds of ashes to keep the liquid from spreading. After 

 24 hours add 20 pounds of flowers of sulphur. Thoroughly 

 mix the compound, ashes and all. When dry, sift thi^ough a 

 sieve with meshes of one-eighth inch. Will keep for 

 months. For downy mildew, mildew and anthracnose. 



