Campbell's 1902 Soil Culture Manual. 



73 



solve the sulphate of copper in a coarse sack. To dissolve the sulphate it 

 should be suspended in a bag composed of cloth that will not shed lint. 

 It will dissolve more quickly in hot water. A stock solution may be made. 

 That is, where ten kerosene barrels of water are to be used, forty pounds 

 of the sulphate may be dissolved at one time. One-tenth by measure, may 

 be taken for each barrel of water. This amount may be used for each 

 fifty gallons of the Bordeaux mixture. The lime must always be slacked 

 separately. 



To secure the most complete slacking of the lime, it is well to use 

 the plan followed by masons in preparing for hard finish, using enough 

 water so the lime is at all times covered with the water and kept from the 

 air. This would mean about twenty-four quarts of water to be used in 

 slacking four pounds of lime. After slacking, it would be well to run it 

 through a line copper seive, stirred to remove all the coarser particles 

 which would clog the nozzle. 



The sulphate of copper and the lime should be mixed only a barrel 

 or a tankful at a time, since some chemical change takes place in a short 

 time rendering it less effective. In mixing the Paris green, London purple, 

 or green arsenoid, the proper amount of poison should be put in a bowl 

 and a little water added, then stir and gradually add water until you final- 

 ly have a thin paste. Add this to the Bordeaux mixture last of all since 

 it has a tendency to settle in the bottom of the barrel or tank. 



It is important that the tank or barrel should be tight. It would be 

 found disagreeable to be wet or slopped either with strong arsenical poisons 

 or Bordeaux mixture. It should be carefully remembered that the opera- 

 tor is handling very strong poison and he should guard himself during the 

 use of it as carefully as possible. The operator will find it much easier to 

 spray with the wind than against it and that it is more convenient if 

 possible to spray when there is little wind. The operator should also re- 

 member that if heavy rains follow soon after spraying, the work is lost. 



With a horse power machine the expense for labor in spraying per 

 acre does not exceed 60 cents. With us the cost of poison for the season, using 

 both Bordeaux mixture and green arsenoid is estimated on 80 acres at 

 about $80.00, or not more than $1.00 per acre. This does not reckon the 

 cost of wear and tear of machinery. We would regard it as wise to supple- 

 ment the work of spraying by efforts to trap the larvae which escape the 

 poison from spraying. The larva after attaining its growth in the apple 

 either falls to the ground with the apple and then seeks some hiding place 

 to pupate or if the apple remains on the tree, leaving the apple crawls 

 down the branch and limbs seeking some possible shelter from the birds. 

 Should it find a loose scale of rough bark it may hide under this. Making 

 use of this instinct of the larvae to get under cover as quickly as possible, 

 many orchardists have found very beneficial results in banding the trunk 

 of the tree with burlap or heavy paper, this in strips 8-10 inches in width 



