368 State Horticultural Society, 



the free acid of the sulphate they form several inert compounds, and 

 only one that has any fungicidal or insecticidal property. This is also 

 true of the new method, if they dry slack their lime with the sulphate 

 solution, or if they use the dry dust Bordeaux prepared by Dr. Bird. 

 I do not know how this is with Leggett's Bordeaux, for I do not know 

 how it is made. When last December I said : "Only when we can 

 grind dry lime and bluestone together can we get a good Bordeaux, that 

 is apply bluestone, sulphate or copper, to our trees," I was wrong on 

 two counts. I have stated above that in a simple aqueous solution, the 

 liquid spray men do put sulphate of copper on their trees, and in the 

 second place, later experiments show that in the grinding of lime and 

 copper sulphate together, the water of crystallization is set free and the 

 same inert compounds are made. The latest method is to grind the 

 lime and sulphate separately and mix them by sifting through a very fine 

 sieve. When this mixture is blown upon the trees, powdered copper 

 siilphate is placed directly upon the fungus, there to slowly but surely 

 do its work. If this proves to be as effective as is hoped, it will be 

 better than the water solution, for it is not at all limited in its application, 

 while copper sulphate solution can be used only before the buds open. 

 As an insecticide for all eating insects both schools use Paris Green 

 or some other arsenical poison. The one adds it to their liquid Bor- 

 deaux, the other to their powdered lime and sulphate. Each can add 

 concentrated lye if deemed advantageous, while only the new school can 

 add sulphate. Both agree in spraying for fungi throughout the season, 

 and this is undoubtedly right. 



As an insecticide for sucking insects the old school uses kerosene 

 emulsion ; the new, lime and a double strength of concentrated lye. 

 Both have a caustic — the one soap — the other lime and lye. But the 

 kerosene in the emulsion, a most valuable ingredient for the destruc- 

 tion of sucking insects, can be used only by the old school. The 

 greater ease, however, with which the lime and lye can be applied, and 

 the cheapness of the dust, may fully compensate for the loss of the 

 kerosene. 



As a fungicide that will not stain the fruit, the old school uses 

 ammoniacal copper carbonate solution, instead of Bordeaux ; the new, is 

 not afraid of staining anything. Their formulae are simple, and the 

 mixtures easily made. For fungous diseases they use ground lime, 

 ground copper sulphate mixed with lime, called "Sal Bordeaux" or "Dry 

 Bordeaux Mixture," sulphur and concentrated lye, if deemed necessary. 

 The lye is hardly needed if the lime is the best, fresh and well burnt. 

 And the sulphur is hardly worth the cost and trouble as a fungicide. 



