50 SPRAYING THE APPLE ORCHARD. 



mixture is ready to be drawn off through the hose. While 

 it is running out the two half barrels are again filled, and 

 when the sprayer has been filled they are allowed to run 

 into the mixing tank while the sprayer is on the way to the 

 orchard. Thus the labor of dipping the mixtures from one 

 barrel to the other is obviated and half the time of mixing 

 is saved, and it is time that costs in spraying. A large hose 

 should lead from the tank to the sprayer and the outlet of 

 the tank should be guarded with fine brass or copper gauze 

 or screening to prevent particles of lime and dirt escaping. 

 The mixture should also be run through a strainer as it 

 enters the spray barrel. 



With good lime there is no reason why by following the 

 above directions a good mixture should not be made, but it 

 is always safest to test the mixture to see that it contains 

 no free copper which will burn the foliage. The best test 

 is that with ferro-cyanide of potassium or yellow-prussiate 

 of potash. Secure five cents worth of the crystals from the 

 druggist and dissolve in ten times their bullc in water. Add 

 a few drops to the Bordeaux mixture. If they remain the 

 same color, it is well made. If they turn bro^vn, there is 

 free copper in the mixture and more lime solution should 

 be added until this reaction does not take place. 



The above formula for Bordeaux mixture is weaker than 

 that usually advised and than we should recommend for 

 potatoes, but for the past few seasons, largely due to the 

 unusual cold, wet weather in May and early June, there 

 has been considerable trouble throughout the country with 

 Bordeaux mixture burning the foliage and russetting the 

 fruit when made by the standard formulas. Less injury 

 has resulted from the more dilute solutions. Extensive ex- 

 periments are now being made to determine the cause of 

 this injury, and how it may be obviated, but until they have 

 been completed it will be safer to use the dilute solution as 

 described above. Probably in normal seasons no injury 

 would result. On account of this injury in wet Aveather it 

 will be well to avoid spraying while the foliage is wet or 



