LABORATORY MANUAL OF HORTICULTURE 



much will be required to spray fifty trees three times ? If copper 

 sulphate costs five and one-half cents a pound and lime a cent a 

 pound, what will be the cost of the material ? 



Problem 2. I have a ten-acre apple orchard. There are forty- 

 nine trees to the acre. I wish to spray this orchard four times. 

 How much Bordeaux mixture will be required, and what will be 

 the cost of the chemicals ? 



REFERENCES : 



Bulletin No. 135, Illinois Agricultural Experiment Station. 



Farmers' Bulletin No. 243, United States Department of Agriculture, 



pp. 5-14. 

 Lodeman, " The Spraying of Plants," pp. 19-45. 



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