20 



This solution is used almost exclusively for the hop aphis. It is 

 quite as effective against other species of aphis. 



The whale-oil soap without the quassia is of somewhat less efficiency. 



FUNGICIDES, AND HOW TO PREPARE THEM. 



Fungicides are mainly preventive in their effects, a fact that should 

 never be forgotten. Their beneficial action is to prevent the growth 

 of the fungus and the germination of the spores. When the fungicide 

 has been washed off by rain or otherwise removed, the prompt appear- 

 ance of the fungus may be expected, as rarely or never are the spores 

 destroyed. The most important fungicides are sulphur and its com- 

 pounds, and the copper salts. In orchard operations sulphur is used 

 mainly for the grape mildew, ordinary commercial sulphur being 

 dusted on the vines. Of the copper sprays, Bordeaux mixture is by 

 far the most important and practically the only one emjDloyed in the 

 Northwest. 



The following description of methods to be used in preparing fun- 

 gicides is quoted from Farmers' Bulletin No. 38, Spraying for Fruit 

 Diseases, prepared by B. T. Galloway, of the U. S. Department of 

 Agriculture: 



BORDEAUX MIXTURE. 



All things considered, it is believed that the best results will be obtained from the 

 use of what is known as the 50-gallon formula of this preparation. This contains — 



Water 50 gallons. 



Copper sulphate 6 pounds. 



Unslacked lime 4 pounds. 



It has been found that the method of combining the ingredients has an important 

 bearing on both the chemical composition and physical structure of the mixture. 

 The best results have been obtained from the use of the Bordeaux mixture made in 

 accordance with the following directions: In a barrel or other suitable vessel place 

 25 gallons of water. Weigh out 6 pounds of copper sulphate, then tie the same in 

 a piece of coarse gunny sack and suspend it just beneath the surface of the water. 

 By tying the bag to a stick laid across the top of the barrel no further attention will 

 be required. In another vessel slack 4 pounds of lime, using care in order to obtain 

 a smooth paste, free from grit and small lumps. To accomplish this it is best to 

 place the lime in an ordinarj^ water pail and add only a small quantity of water at 

 first, say a quart or a quart and a half. When the lime begins to crack and crumble 

 and the water to disappear, add another quart or more, exercising care that the lime 

 at no time gets too dry. Toward the last considerable water will be required, but if 

 added carefully and slowly a perfectly smooth paste will be obtained, provided, of 

 course; the lime is of good quality. When the lime is slacked add sufficient water 

 to the paste to bring the whole up to 25 gallons. When the copper sulphate is entirely 

 dissolved and the lime is cool, pour the lime milk and copper sulphate solution slowly 

 together into a barrel holding 50 gallons, as shown in figure 1. The milk of lime should 

 be thoroughly stirred before pouring. The method described insures good mixing, 

 but to complete this work the barrel of liquid should receive a final stirring, for at 

 least three minutes, with a broad wooden paddle. 



It is now necessary to determine whether the mixture is i)ei'fect — that is, if it will 

 be safe to apply it to tender foliage. To accomplish this, two simple tests may be 



