280 STATE BOARD OF AGRICULTURE. 



REMEDIES FOR THE SCALE. 



For the last ten years experiments with various remedies for the scale 

 have been tested. Among the first was whale-oil soap, and when a potash 

 soap was used at the rate of two pounds in a gallon of water it made a 

 fairly effectual remedy, but as it cost seven or eight cents per gallon for 

 the diluted mixture, it was rather expensive treatment. Kerosene and 

 crude petroleum both in a pure state and in soap and mechanical emul- 

 sions were next recommended. Especially upon peach trees, the use of 

 kerosene and petroleum often resulted disastrously from the fact that 

 it was very difficult to secure uniformity in the emulsions. To destroy 

 the scale it is desirable to have 20 to 25 per cent of oil in the emulsion, 

 and if the oil separates there is always danger on the one hand of in- 

 juring the trees and on the other of not having it strong enough to kill 

 the scale. It sometimes happens that the presence of scale in an orchard 

 is not noticed until after growth has started and if sufficiently numerous 

 to do much harm to the trees, it will be well to spray the trees when the 

 insects are in the larval form, as at that time they can be destroyed with 

 remedies that can be applied without injuring the trees. A kerosene 

 emulsion made with 10 per cent of oil for apple trees and 8 per cent for 

 all others, used about the first of July and then if necessary, at the last 

 of August, will do much to keep down the numbers and thus lessen 

 the injury to the trees until the time comes when the more powerful 

 applications can be used. 



THE SULPHUR AND LIME MIXTURE. 



Some years ago it was ascertained by California fruit growers that a 

 mixture containing sulphur, lime and salt, which they were using as a 

 sheep dip, was a very effectual remedy against the San Jose scale. It 

 has now been thoroughly tested in the eastern states and is generally 

 regarded as the cheapest, safest and in every way the best remedy. 

 Many persons are omitting the salt, but it seems to have some value in 

 holding the mixture upon the trees in case heavy rains occur. In Oregon 

 the salt was replaced by four or five pounds of copper sulphate for fifty 

 gallons of the wash, but this seems to add nothing to its value even as a 

 fungicide and it may well be omitted. 



In order to secure results from this mixture, the sulphur must be 

 brought into chemical combination with the lime so that it will dissolve 

 in the water. This can only be secured by the application of heat and in 

 the preparation of the sulphur and lime mixture, it is always necessary 

 to boil it for forty-five to sixty minutes either with a fire or by the use 

 of steam. 



When only a small quantity is to be prepared an iron kettle can be 

 used for boiling the mixture. If it can be jacketed, or set in brick work, 

 it will result in economy of fuel and will also facilitate the boiling. 

 There are also various stock-food cookers that answer Avell for boiling 

 the sulphur and lime mixture. When steam is used, it can be furnished 

 from a traction engine or by the use of a small, steam boiler. There are 



