268 FARM FRIENDS AND FARM FOES 



For spraying dormant trees in winter or early spring, it is 

 used at the rate of one pound dissolved in fifty gallons of 

 water. For spraying trees in leaf it is used at the rate of 

 two ounces dissolved in fifty gallons of water. 



Carbonate of copper is also used as a fungicide. It is 

 generally prepared as follows : Three ounces of the car- 

 bonate are to be dissolved in three pints of ammonia, the 

 whole then being added to a barrel of water. The pow- 

 dered carbonate dissolves more readily if it is first made 

 into a paste by mixing with water. One advantage of this 

 fungicide, which is used for the prevention of apple scab 

 and various mildews, is that, being a clear solution, there is 

 no clogging of nozzles, as sometimes happens with the Bor- 

 deaux mixture. 



Sulphide of potassium or liver of sulphur is sometimes 

 used to prevent the mildew on the leaves and fruit of goose- 

 berries. Half an ounce is dissolved in two gallons of hot 

 water, and the solution when cold is applied to bushes in 

 the form of a spray. 



Powdered sulphur, commonly called flowers of sulphur, 

 is valuable as a fungicide for some forms of fungi affecting 

 plants. It is used in California as a preventive of asparagus 

 rust. The fumes that rise from the sulphur on the hot soil 

 in sunshine kill the rust spores. 



The lime-sulphur spray used as a remedy for scale in- 

 sects is also a fungicide. It has proved one of the best 

 remedies for peach-leaf curl, brown rot of stone fruits, apple 

 scab, and other diseases. 



Solutions of formalin have been found of great value as 

 fungicides in the treatment of potato scab and grain smuts. 

 Fortunately, this substance is now taking the place of cor- 

 rosive sublimate — a poison too dangerous to use unless 

 absolutely necessary. 



