Fungous Diseases of Garden Plants. — 135 



(as the roots of fungi are called) after it has once entered the tis- 

 sues of the attacked leaf, stalk, or berry. In short, the only way 

 of successfully fighting fungi which attack foliage, consists of 

 covering the yet unattacked leaf or stalk with a coat which the 

 germinating spore is powerless to penetrate, or which kills every 

 spore which tries to get a foothold upon it. 



To provide such a coat of mail is the purpose of spraying 

 with fungicides. The safety of the foliage is insured only so 

 long as all its parts are thus protected. This also explains the 

 need of repetitional treatments, especially immediately after heavy 

 or long-continued rains, which are liable to wash the protective 

 armor off, and leave the foliage more or less exposed. Young 

 leaves, usually and fortunately, are less subject to the attacks of 

 fungous diseases than older ones ; but in time the new growth of 

 young leaves becomes old, and will also require treatment. 

 Hence we must not only spray early, but also repeatedly, and 

 the oftener, the more favorable the season appears to be to the 

 development of plant diseases. 



Spore-Killing Mixtures. — A great number of different 

 solutions and mixtures have been tried and recommended for 

 their fungicidal (spore-killing) properties ; but there are only a 

 very few deserving general consideration. 



Bordeaux Mixture. — For the purpose of supplying the 

 protective covering spoken of, nothing has as yet been found 

 superior or even equal to the copper and lime compound called 

 "Bordeaux mixture," or "copper mixture ofGironde." The 

 adhesive nature of the lime tends to glue the copper firmly to the 

 foliage. Consequently the mixture will stick longer than any 

 other fungicide yet suggested, and even through moderate rains. 

 Professor Galloway, of the United States Department of Agricul- 

 ture, recommends the following method of preparation : " In a 

 barrel that will hold forty-five gallons, dissolve six pounds of 

 copper sulphate (blue vitriol, bluestone), using eight or ten gal- 

 lons of water, or as much as may be necessary for the purpose. 

 In a tub or half barrel slake four pounds of fresh lime. When 

 completely slaked, add enough water to make a creamy white- 

 wash. Pour this slowly into the barrel containing the copper 

 sulphate solution, using a coarse gunny sack stretched over the 

 head of the barrel for a strainer. Finally fill the barrel with 

 water, stir thoroughly, and the mixture is ready for use." 



I find it more convenient, however, to make the mixture in 

 a slightly different manner. First get the required ingredients 

 and receptacles, viz. : the copper sulphate (or bluestone) ; fresh 

 lime ; a vial containing a solution of yellow prussiate of potash ; a 

 barrel, vat or tank large enough to hold the required quantity of 



