53G STATE BOARD OF AORTCTILTURE. 



SUGGESTIONS,* 



For the beiielit oi" rruit growers wlio may care lo use the dusting method 

 at this time, a few suggestions may prove helpful. 



A duster of sufficient capacity and power should ho used. Efficient 

 w^ork cannot be done with an undersized machine. 



Special dusting sulphur should always be used. The ordinary grades 

 of sulphur are not satisfactory. 



Home-mixing of materials slionld not l»e tried unless a special mixing 

 machine is used. 



Applications should be made from two opposite directions and prefer- 

 ably when there is not any wind. 



Unlike spraying, dusting can be safely done when the foliage is wet. 



More applications of dust than are usually made of the liquid sprays 

 will probably be desirable. However, the number will depend largely 

 upon weather conditions. The applications of dust should, of course, be 

 made before scab infection periods. Cool and rainy weather is favorable 

 to scab development. 



BORDEAUX MIXTURE. 



Bordeaux mixture is made of copper sulphate, lime and water. 



These three substances are combined in various proportions, depend- 

 ing upon the kind of plant to be treated. For apples, pears, cherries and 

 plums (excej)t Japanese varieties) the preparation is usually four 

 pounds of copper sulphate, with about the same amount of lime, to fifty 

 gallons of water. Poison is added as needed. The copper sulphate Avill 

 readily dissolve in two gallons of hot water, to which should be adde<l 

 enough water to make 25 gallons, or one-half barrel. Do not use an 

 iron or tin vessel to dissolve this in, as the copper sulphate will destroy 

 it, and besides the iron will spoil the Bordeaux. A wooden pail is good. 

 Slake the lime into a thin paste and add water to make 25 gallons. Pour, 

 or let these run together into a third barrel, and the Bordeaux is maih'. 

 When it is emptied into the spray barrel or tank, it should be strained 

 through a brass wire strainer to catch any of the coarse particles. 



Whenever it is necessary to use a quantity of the mixture, it is desir- 

 able to have the lime and copper sulphate in "stock solutions." A 

 quantity of lime is slaked to a paste and held so by being covered with 

 water. The copper sulphate, say 50 pounds, is placed in a clean gunny 

 sack and suspended in a barrel (one witli wooden hoo]^s is much to be 

 preferred) containing 25 gallons of watei-. Tliis will dissolve in about 

 a day. One gallon of this ''stock solution"** is equal to two pounds of 

 copper sulphate. 



A good quick way to combine these thre<' substances is as follows: 

 Put the amount of the "stock solution" of cop])er suli)liate required in a 

 barrel, and add enough water to make 25 gaHons, or one-half barrel. 

 Put about 7 pounds of the lime paste in a barrel and add 25 gallons of 

 water, making a thin whitewash. Pour, or let these two run together 

 into a third barrel, or directly into the spray barrel or tank, being sure to 

 strain. When partly run in, test with ferro-cyanide of potash to make 



*Prom Special Bulletin No. 87. Dusting and Spraying Experiments with Apples. 

 **AJways stir this '■stocij solution" before clipping any out, in order that what is used may be 



