1893.] PUBLIC DOCUMENT — No. 33. 245 



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must be taken that the sulphur does not become so hot as 

 to take fire, as a brief exposure to the fumes of burning 

 sulphur will kill cultivated plants, as well as fungi. But a 

 little experience will soon enable one to set the flame of the 

 oil stoves at such a height that it can be safely left to do its 

 work. 



If the plants to be protected are out of doors, it is evident 

 that we cannot use sulphur vapor. Here we must rely on a 

 direct application to their surfaces. Dry flowers of sulphur 

 scattered upon the plants or blown upon them with a bellows 

 is often of considerable service. But a solution sprayed 

 upon the plants, by means of some of the spraying machines 

 recommended in previous publications of this department,* 

 is much more efBcient. Formulae for several solutions may 

 be found in the publications just referred to,* but that most 

 generally applicable and most satisfactory in its application 

 and in its results is the ammoniacal carbonate of copper. 

 The formula for this fungicide may be, for convenience, 

 repeated here : mix one ounce carbonate of copper with five 

 ounces carbonate of ammonia, and dissolve in one quart hot 

 water. When dissolved, add sixteen gallons water. This 

 may be used to thoroughly spray the plants as often as the 

 presence of the fungus in harmful quantities shows it to be 

 necessary. For spraying a few plants only, such as a few 

 rose or gooseberry bushes, hand sprayers may be purchased 

 at a price much below that of the cheapest knapsack sprayer. 

 But care should be taken that the apparatus used throws a 

 very fine, mist-like spray. Full directions and suggestions 

 as to spraying in general may be found in the previous 

 publications of this department on the subject. 



* See Bnlletin No. 39, Massachusetts Experiment Station, and Ninth Report 

 Massachusetts Experiment Station, pp. 239, 240. 



