13 



The following tests will show whether the copper-sulphate has all been 

 neutralized by the lime: 



Potassium ferroeyanide (in solution) No change on adding to mixture. 

 If more lime is required it turns a purple or reddish colour. 



Blue litmus-paper No change. If more lime is required it turns a red 

 colour. 



Knife-blade If metallic copper precipitates on the blade the mixture 

 requires more lime. The potassium ferroeyanide is the best and cheapest 

 indicator. 



Bordeaux mixture is to be recommended where the disease is serious. 

 In other places the use of lime-sulphur will be satisfactory and more 

 economical, as besides its fungicidal value it has considerable insect icidsil 

 value. 



SPRAY OUTFITS. 



As far as results in spraying for canker are concerned, the type of 

 sprayer makes little difference providing thorough work is done. With old 

 trees a sprayer will be required which will give higher pressure than is 

 required on a younger tree, in order to fill all cracks in the bark. In all cases 

 high pressure is an advantage from the standpoint of economy, as double 

 pressure means approximately double quantity applied or double area covered. 

 With the present scarcity of labour and the high labour values which prevail, 

 this is a distinct advantage. Time is also an important consideration, .as the 

 writer has seen 50 per cent, difference in results in a difference of three days' 

 time to control some of the pests of our orchards. In buying an outfit the 

 fruit-grower should not select his type from the standpoint of his present 

 necessities, but look to his requirements for the near future during at least 

 part of the lifetime of his outfit. Improvement in spraying-machines is taking 

 place so rapidly that it is impossible to say which outfit will be the best for 

 the next few years, though it is better to select one that has a larger capacity 

 than the present requirements demand, simple in construction, strong, easily 

 worked, easily cleaned, and one in which high pressure can be maintained. 

 See that the pump especially, and, as far as possible, the parts with which 

 the mixture comes in contact, will not be damaged by the spray, causing 

 frequent renewal and trouble in clogging of nozzles, etc. A few figures on 

 comparative value of spray outfits are given here for the consideration of 

 prospective buyers of outfits. These figures will vary in different districts 

 under different conditions, but the basis for comparing values, providing they 

 are correct, remains constant. It will be noted here that the first cost is 

 largely a secondary consideration, and that the main expense in spraying is 

 due to the cost of labour, which varies with the capacity of the outfit in use. 



COMPARATIVE A'ALUE OF SPRAY OUTFITS. 

 Basis 200 barrels annual output. 



(I.) Barrel Hand-pump. 

 Initial cost, $25.00. 

 Number of barrels per day, 10. 



Interest on investment, 7 per cent $ 1 75 



Depreciation in value, 10 per cent 2 50 



Twenty days, two men at $2.50 100 00 



Twenty days, horse at $2.00 40 00 



$144 25 



