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A Few Suggestions for Increasing Man Power by Using Bigger Teams and More Machines
出版U.S. Department of Agriculture, 1919
URLhttp://books.google.com.hk/books?id=ZPaVF4mlPMMC&hl=&source=gbs_api
EBookFULL_PUBLIC_DOMAIN
註釋"Bordeaux mixture is the only reliable preventative for certain diseases of plants and must be used despite th present high price of copper sulphate. Since commercial Bordeaux mixtures vary widely in copper content it is necessary for the grower to know their strength in terms of the amount of equivalent copper sulphate in 50 gallons when diluted. This can easily be calculated by the method described in this bulletin or can be approximately determined without calculation by reference to Tables I and II. After the strength of the product is known, the relative money value of its ingredients can be easily calculated. Physical properties, such as adhesiveness, texture, spreading quality, and rate of settling also are important factors in determining the efficiency of Bordeaux mixtures. The grower should regard spraying as an insurance and preventative and should always be prepared for an epidemic of the disease he expects to combat. If he wishes to insure good control, he should, therefore, use a preparation equivalent to the standard Bordeaux mixture recommended for that purpose."--Page 2.