VANILLIN AS A SOIL CONSTITUENT 



323 



and a good sample of Hagerstown loam. The paraffined wire 

 pot method 6 was used, six wheat plants were grown in each pot, 

 and two pots were used for each treatment. The plants grew 

 from May 5 to May 24. Photographs of the growing plants 

 were taken, which show the action of vanillin in each soil. At 

 the end of the experiment the green weight was determined. 



The Florida sand used in this experiment had grown citrus 

 fruits in the field and was unproductive. A laboratory exami- 

 nation showed the soil to be acid. Vanillin was isolated from 





■nSCAw 



Fig. 1. Effect of vanillin on clover. (No. 1, Soil untreated. 2, Soil plus 



vanillin.) 



this soil in the investigations referred to above. The Susque- 

 hanna sandy loam was taken from an infertile area in Maryland. 

 The natural growth on this soil was poor, and its response to 

 fertilizer and cultural treatments was only moderate. Its oxi- 

 dizing power and life activities were found to be very weak. 

 The Hagerstown loam is a fertile soil. The soil was taken from 

 a productive field of the Pennsylvania Agricultural Experiment 

 Station. The soil is neutral in reaction, has strong oxidizing 

 power, and grows thrifty plants in pots. 



6 Cir. 18, Bureau of Soils. 



