FOOD FOR PLANTS 157 



Sod Culture . 

 vrith 

 300 lbs. Nitrate Cultivation 



Year of Soda per acre without Nitrate 



Average 1921 130 lbs.* 77 lbs.* 



yield 1922 371 " 264 " 



in pounds 1923 259 " 158 " 



per tree 1924 389 " 168 " 



Four-year average 287 lbs.* 167 lbs.* 



Per cent increase due to Nitrate of Soda — 72%. 



In the Round Hill Orchard at Winchester, where 

 the Virginia State College Experiment Station has 

 conducted experiments on 25-year-old York Im- 

 perials for four years, one tree which had had seven 

 pounds of Nitrate of Soda for four years yielded 762 

 pounds in 1924; one tree from check plot yielded only 

 244 pounds. 



Average Yield per Tree in Pounds. 



Year 



1923 



1924 



In a Rome Beauty Orchard in Southern Ohio, 

 where the Extension Department of the Ohio State 

 University is conducting experiments on plots which 

 have had no fertilizer for a period of three years, the 

 average response per tree the second year from the 

 use of five pounds of Nitrate of Soda and five pounds 

 of acid phosphate was, from the fertilized plot 13.2 

 bushels; from the check plot 2.1 bushels. 



* The average weight of a bushel of apples is 48 lbs. 



