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the part of those interested. One man may destroy the diseased leave* 

 in his vineyard, but his neighbour may think that sort of thing a waste 

 of time, and as a result the fungus spores that winter over in his place^ 

 will be sufficient to infect all the vineyards for miles around. 



The second plan of warfare consists in applying substances to the 

 parts of the plants subject to attack that will destroy the spores of the 

 fungus but not injure the host plant itself. This method by tar the- 

 most extensively used, as it renders every one independent of what his 

 neighbour may do. Copper is at the present time the principal weapon 

 u»ed in this warfare. This poison in almost infinitesimal quantities is 

 found to destroy quickly the reproductive bodies of some of the most 

 destructive fungi and at the same time it is applied in such a way as to 

 be perfectly harmless to the host plant and what is more important to 

 man himself. 



Probably no less than twenty-five different forms of copper are 

 used for forming the basis of these fungicides, chief among which may 

 be mentioned copper sulphate, or blue-stone, copper carbcmate, copper 

 acetate, and copper phosphate. It is hardly necessary to go into the 

 details of how these various substances are prepared, it being sufficient 

 for our purpose to say that a great deal of experimental work has been 

 necessary to insure a preparation that would fill the chief requirements, 

 which are cheapness, ease of preparation and application, fungicidal 

 •fficiency, and adhesiveness. One of the fungicides admirably filling all 

 the foregoing requirements is made by adding a whitewash or milk of 

 lime to a solution of bluestone. Bluestoue solution was tried and was 

 found to injure the foliage badly ; moreover, the first rain removed it. 



Next to fungicides the manner of applying them is the most im- 

 portant. It has been found that unless the various solutions are finely 

 und evenly distributed over all parts of the plant subject to attack much 

 of their value is lost. Machines are now made especiallv for this work,, 

 many of them being devised and others perfected by the Agricultural 

 Department. The machines of this kind consist mainly of a strong 

 force pump, a reservoir for holding the solution, and a nozzle for mak- 

 ing a spray. By means of the force pump, which may be worked either 

 by a hand or horse power, the liquid is drawn from a suitable tank and 

 forced through a rubber hose of small bore to the spraying nozzle, 

 where it issues forth as a fine, mist-like spray. Horse power machines 

 •mbodying these various parts are now made which will thoroughly spray 

 an acre of bearino: vines in 40 or 45 minutes. To get a more definite 

 idea as to how work of this kind is carried on let us follow for a 

 moment one who is preparing to treat his grapes for black-rot. 



In thf first place, thoroughly to appreciate the importance of doing 

 everything promptly and at the right time, the man must know that 

 the reproductive bodies or spores of the black-rot fungus live over 

 winter in the old berries, that these escape in spring and infect the 

 young leaves and fruit before the former are fully grown and the latter 

 are the size of bird shot. Furthermore, he must know that the spores 

 are present throughout the growing season every ready to infect newly 

 exposed parts. With this knowledge in his possession, it needs no 

 great amount of argument to convince him that to be successful he must 



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