Insecticides and Fungicides. 245 



26. Copper Carbonate Mixture. 



Copper carbonate 1 pound 



"Water 50 gallons 



Mix the copper carbonate into a paste with a little water before attempt- 

 ing to add it to the fifty gallons. 



27. Copper Acetate Solution. 



Dibasic acetate of copper 6 ' ounces 



Water 50 gallons 



Use finely powdered acetate of copper, mix it into a paste with a little 

 water, then dilute with the full amount of water. 



28. Potassium Sulphide Solution. 



Potassium sulphide 1 ounce 



Water 2 to 3 gallons 



Dissolve the potassium sulphide in the water. 

 Valuable as a spray for mildews. 



29. Corrosive Sublimate. 



Corrosive sublimate 1 ounce 



Water 7 to 8 gallons 



This is valuable as a preventive of potato scab. In a wooden vessel, dis- 

 solve the poison in one gallon of water, then dilute to the full amount. Place 

 the scabby seed potatoes in a sack, immerse them in tlie solution and allow 

 them to soak one to two hours. The solution and the treated potatoes are ex- 

 tremely poisonous. 



30. Formalin. 



Formalin, a 40 per cent solution of formaldehyde gas in water, is being 

 used extensively as a preventive of potato-scab and of the grain-smuts, and 

 gives most excellent results. It is cheap, efficient and non-poisonous. For po- 

 tato-scab, soak the seed two hours in the following solution : 



Formalin i/i pint 



Water 15 gallons 



For grain-smuts soak the seed for one to two hours in the following : 



Formalin 1 pint 



Water 50 gallons 



METHODS OF TREATMENT FOR INSECT PESTS AND PLANT DISEASES. 



Apple. — For apple-scab, spray with 22; first, when fruit buds are swelling; 

 second, when blossoms are unfolding: third, after petals fall; and thereafter 

 every 10 days or two weeks as long as wet weather persists. For codling moth. 

 add Paris green or one of the arsenic sprays to the Bordeaux for the third and 

 subsequent applications ; then begin late in June and spray every two weeks 

 with 1 or 2 until three weeks before the fruit is to be picked. If trees are in- 

 fested with San Jose scale spray with 10 or 11 when trees are dormant. For 

 green-aphis, use 13. as soon as leaf buds start and repeat whenever the aphis 

 Tjecomes abundant on the foliage. For woolly-aphis, branch-form, use 13 ; for 

 root-form, use 16 or 19. For tingis, spray with 13 when eggs are hatching and 

 practice clean ciilture. For apple-tree anthracnose, spray as soon as possible 

 after crop is gathered with 21 and repeat in two weeks ; write for bulletin No. 60. 



Barley. — To prevent smut use 30. 



BeoM. — For anthracnose, soak seed in 30 ; when plants are two or three inches 

 liigh spray with 22 and repeat two or three times at intervals of 10 or 12 days. 

 For weevil, fumigate seed with 19. 



