GENERAL PRACTICE. ENEMIES. 261 



in 1 gallon of water, in which boil the sulphur until dissolved [15 minutes]. Then 

 dissolve the soft soap in the water intended for the wash, after which pour into this 

 the dissolved soda and sulphur, mixing the two together, and boil for a short time. 

 Use this as a spray with an ordinary spray pump while hot [90 to 100]. This wash 

 we apply early in the summer, and it acts as a preventive against the perfect insect laying 

 its eggs, or it destroys any that may be hatched out, having escaped the winter spray 

 (page 259), and destroys any fungoid disease. It will not injure the foliage or young 

 fruit." 



This is a very valuable combined fungicide and insecticide. In ordinary seasons it is 

 all that is necessary to destroy mildew, apple-scab fungus, aphides, and red spider. The 

 soft soap contained in the wash may prejudicially affect apple foliage, and a 2-ounce 

 solution of soft soap to a gallon of water is sufficiently strong. With 7 pounds of soft 

 soap instead of 14 pounds the wash effectively eradicates aphides and red spider. 

 Growers in America have to contend with many scale insects ; besides, the foliage there 

 is harder than in this country. 



Eesin compounds make speedy work on aphides, and are sure against young scale. 

 Formula : Caustic soda, \ pound ; resin, 4 pounds. Dissolve the caustic soda in \ 

 gallon of boiling water, add the resin slowly, and boil until dissolved, stirring rapidly, 

 and then add 2^ gallons of water, mixing well. Strain through a thin cloth, while hot. 

 Use 1 quart of the compound to 3 gallons of water at a temperature of 100, and spray 

 upwards so as to reach the under side of the leaves. This will destroy the green aphis, 

 but it is sometimes needful to use the wash stronger for black fly ; yet it is necessary 

 to ascertain the strength that can be borne by the leafage of the trees before applying 

 the wash wholesale. 



Petroleum mixtures are very effective against aphides, but, unless care is exercised 

 in preparation and application, may be injurious to young bark. The following is gene- 

 rally safe : soft soap, 1 pound ; petroleum, \ pint ; water, 10 gallons. Dissolve the soft 

 soap in a gallon of boiling water, add the petroleum, and, with a force-pump, drive the 

 liquid back into the vessel holding it for two or three minutes ; then add the remainder 

 of the hot water, continuing the pumping as before, whilst it is being added rather 

 slowly. Use as a spray as hot as the hand can be borne in it for ten seconds, and always 

 towards evening. It is the action of hot sun on the wet leaves that causes scorching. 

 Petroleum mixtures are safest applied with a pump having two deliveries, one keeping 

 the liquid agitated whilst spraying is effected by the other. 



