42 LEAD ARSENATE. 



vations had been made. This would seem to indicate very strongly 

 that practically all the injury resulted from this last application. 



SUMMARY OF RESULTS FOB THE TWO YEARS' EXPERIMENT. 



No injury resulted to apple foliage in either 1907 or 1908 from 

 three applications of lead arsenate, made from sodium arsenate and 

 lead acetate, or sodium arsenate and lead nitrate, when applied at 

 the rate of 1J pounds (dry basis) to 50 gallons of water. 



No injury resulted to apple foliage in 1908 from the use of lead 

 arsenate made by the two methods, from which the salts formed as 

 by-products were not removed, when applied the same number of 

 times and at the same rate. (This experiment was not tried in 1907.) 



No injury was caused to the foliage of the apple in 1907 or 1908 

 by three applications of lead acetate or lead nitrate in strength 

 greater than would occur in any but the most carelessly made lead 

 arsenate. 



No injury was caused to the foliage of the apple in 1907 or 1908 

 from three applications of sodium acetate and acetic acid, acetic acid 

 alone, or sodium nitrate, a in strengths produced from the amounts 

 formed in the preparation of 1J pounds of lead arsenate by the two 

 methods, made to 50 gallons. These results were expected, as lead 

 arsenate is being used in apple orchards very extensively in all parts 

 of the country and with success. 



No noticeable injury resulted to peach foliage in 1907 from two 

 or three applications of lead arsenate (made by the two methods) 

 at the rate of 1J pounds (dry basis) to 50 gallons of water. The 

 fruit from these trees was a bright red color, which was desirable 

 rather than otherwise, as its quality was not impaired. 



Three applications of lead arsenate of the same strength (made 

 by the two methods) in 1908 caused very marked injury to peach 

 foliage and also to the fruit. The same when applied with lime in 

 the proportion of 4 pounds to 50 gallons produced considerable 

 injury, but to a less extent. Injury to the fruit was decreased about 

 50 per cent by the use of lime. 



In 1908 three applications of lead arsenate, made from sodiu 

 arsenate and lead acetate, and from sodium arsenate and lead nitrate 

 without removing the salts formed as by-products, resulted in the 

 same injury as from the use of the washed product. The same 

 applied with lime at the rate of 4 pounds to 50 gallons produced about 

 50 per cent less injury to the fruit. 



Three applications of lead nitrate, in the proportion of 2.1 ounces 

 and 4.2 ounces to 50 gallons of water, produced slight injury to peach 



<* Lodeman reports injury to the foliage of apple and quince from the application 

 of nitrate of soda at the rate of 2 ounces in 2 gallons of water. Cornell Agr. Exper. 

 Sta., 1893, Bui. No. 60, p. 291. 



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