GENERAL PRACTICE. DISEASES, 241 



added, 1 pound to 10 gallons of water, and liquid sulphur preparation the lime 

 and sulphur mixture just noted diluted with 180 parts of water, were all more or 

 less beneficial, while a solution formed by dissolving 1-J. ounce of carbonate of copper 

 in a quart of liquid ammonia, and diluted with 90 quarts of water, was almost 

 a complete remedy for the disease. Spraying the trees commenced on May 18, 

 when the petals had fallen from the flowers but the young fruits were scarcely larger 

 than peas, and repeated on May 30, June 4, June 17, July 1, July 24, and August 10. 

 These sprayings with ammoniacal carbonate of copper solution, so fur prevented the 

 growth of Cladosporium as to increase the number of first quality fruits more than 3- 

 times, and to decrease the number of third quality fruits nearly 14 times. Trees sprayed 

 as above gave the following percentages : first quality fruits, 75*0 ; second quality fruits, 

 2 3 -4 ; third quality fruits, 1-6. Unsprayed trees : first quality fruits, 233 ; second 

 quality fruits, 54-0 ; third quality fruits, 22'7. These figures hardly do full justice to 

 the beneficial effects of the spraying with the ammoniacal carbonate of copper solution, 

 because the fruits from the sprayed trees would necessarily represent a much superior 

 average quality to those of the corresponding grades from the unsprayed trees. 



The Wisconsin ammoniacal solution of carbonate of copper found so successful 

 against apple scab, represents a strength of ounce of carbonate of copper and 4 ounces 

 of ammonia to 10 quarts of water =21 gallons, or 1 ounce of carbonate of copper and 

 36 ounces of ammonia to 20 gallons of water. These figures may be useful to amateur 

 growers having few trees, also to those using other formulas in the preparation of 

 ammoniacal carbonate of copper solutions, showing (as they do) the strength at which 

 they must be used in spraying apple trees for the prevention of scab. Although the 

 apple is the commonest of fruit trees, its foliage is more susceptible to injury 

 through the action of fungicides than that of most others; this must be remembered 

 by growers, for when the ammonia is too strong the leaves are injured and the fruit 

 rusted. 



During 1891 another series of experiments were conducted by Professor Goff, 

 with precipitated carbonate of copper in suspension, for preventing apple scab. An 

 ounce of carbonate of copper was first well stirred in a small quantity of water, and the 

 mixture thus formed was added to 12 gallons of water. Four sprayings were given- 

 two before the trees blossomed and two afterwards, and the result was: first quality 

 fruit, 16-34 per cent. ; second quality, 77'43 ; third quality, 6-23 = 100. Unsprayed- 

 first quality fruits, 0-36 per cent.; second quality, 08-98; third quality, 30-66 = 100. 



VOL. I. II 



