206 SCHOOL AND HOME GARDENS 
The standard Bordeaux mixture may be used success- 
fully on plants whose leaves are not easily injured. It 
hurts the foliage of peach trees and may also discolor 
the fruits of apple or pear trees. The strength may be 
decreased or increased as desired. 
The 5-5-50 formula is copper sulfate, five pounds ; 
lime, five pounds; water, fifty gallons. By reducing the 
quantity of copper sulfate and increasing the lime, the 
danger of scorching may be lessened. 
Peach Bordeaux mixture, or the 8-9-50 formula, is 
copper sulfate, three pounds ; lime, nine pounds; water, 
fifty pounds. This formula is used extensively for 
spraying peach trees, and is not likely to injure the 
foliage. 
Bordeaux mixture and insecticide. To fifty gallons of 
Bordeaux mixture add four ounces of Paris green or 
three pounds of lead arsenate. 
Potassium sulfide. Use one ounce of potassium sul- 
fide in three gallons of water. This does not discolor the 
leaves. It is especially effective in preventing mildews 
and rusts. 
Sulfur. Flowers of sulfur is used to prevent mildews, 
such as that of the rose. Dust the powder over the 
plants when they are damp. 
Formalin. Formalin is used very extensively for pre- 
venting scab on seed potatoes. Use one ounce of 
formalin to two gallons of water. 
