FIGHTING THE RED SPIDER 473 



Sulfid of Potash Stock Solution. Granulated, powdered concen- 

 trated lye, 15 pounds; sulphur, 18 pounds; water to make 20 gallons. 

 Stir the sulphur and lye together in a vessel which will allow plenty 

 of room for boiling. When well mixed, add about one pint of water, 

 placing it in a slight hollow in the mixture, and stir in slowly. The 

 mixture will soon begin to melt and boil, forming a red fluid; stir 

 until the boiling ceases, and then add water to make 20 gallons. This 

 stock solution will keep for awhile, or indefinitely when protected from 

 the air. 



Preparation of the Spray Mixture with Sulfid of Potash. Place 

 10 to 15 pounds of sublimed sulphur, or 14 to 20 pounds of ground 

 sulphur in a spray tank with 4 gallons of flour paste and 1 to 2 gallons 

 of the sulfid of potash stock solution; add water to make 100 gallons. 

 For summer or spring spraying after the danger of rains is over, 

 the minimum amount of sulphur is sufficient. 



Flour-paste Spray for Red Spider. Mr. W. B. Parker of the 

 Bureau of Entomology of the U. S. Department of Agriculture has 

 demonstrated the efficacy of a paste spray to be used during the 

 summer while the insects are active: 



Take 8 pounds of cheap flour and stir into a thin batter by adding a little 

 cold water at a time until 8 gallons of water is used. Mash out all lumps. 



Cook until paste is formed, stirring constantly to prevent caking or burning. 

 Cooking slowly until the paste just begins to boil will usually be about right. If 

 the paste is not sufficiently cooked, the resulting spray will not be effective, and 

 if overcooked the paste will harden when thoroughly cool, and will not mix 

 with water very readily. 



Add cold water to the properly cooked paste, to make 100 gallons in the 

 spray tank. Keep constantly stirred while spraying. Apply thoroughly to both 

 the upper and under surfaces of the leaves. Use a nozzle making a coarse spray 

 under 150 Ibs. pressure, as the driving force is necessary to penetrate the webs 

 and reach the spider. A fine mist spray would not be effective. This is a 

 contact insecticide and the liquid must actually touch the spider. Watch care- 

 fully, and if newly hatched spiders are appearing, repeat the spraying in about 

 seven days. Commercial paste, ready for diluting, can be purchased if desired. 



Phylloxera. This pest of the grape-vine is closely allied to the 

 aphides, and lives both upon the root and leaf, though in this State 

 the root type prevails and the leaf form is seldom seen. No remedy 

 has yet been found effectual, but escape is had by using roots resisting 

 the insects, as described in Chapter XXVI. The insects are recognized, 

 by the aid of a magnifier, as minute yellow lice, chiefly on the rootlets. 

 Full account of the insect is given in Bulletin 192, University of 

 California Experiment Station. 



The Woolly Aphis. A louse of dark red color, occurring in 

 groups, covered with a woolly substance which exudes from the 

 bodies of the insects. The woolly aphis is an almost universal pest of 

 the apple, though as shown by experience, some varieties are prac- 

 tically exempt from it. As the pest lives both upon root and top, its 

 annihilation is impossible, but it may be reduced so that the fruitful- 

 ness and vigor of the tree are not impaired. The use of wood ashes 

 around the tree close to the trunk has been beneficial. Removing the 

 earth above the main roots, in a circle two to four feet in diameter 

 and soaking the ground with kerosene emulsion, using from three to 



