BULLETIN OF THE 



No. im 



Contribution from the Bureau of Soils, Milton Whitney, Chief 

 January 30, 1915. 



(PROFESSIONAL PAPER.,) 



FIELD TEST WITH A TOXIC SOIL CONSTITUENT, 



By J. J. Skinner, 

 Scientist in Soil Fertility Investigations. 



INTRODUCTION. 



The presence of vanillin in soils and in a number of plants has led 

 to a study of its effect on growth. Its harmful effect on wheat plants 

 in water and nutrient culture solutions has been demonstrated, while 

 the experiments reported in this paper deal with its effect in soils on 

 crops grown in the field and in pots in the greenhouse. 



Until recently vanillin had not been definitely isolated or identified 

 in soils, but much information had been obtained in the work of this 

 laboratory to indicate its presence in a number of soils. The isolation 

 of vanillin in crystal form from certain soils and its definite identi- 

 fication has now been accomplished 1 and its effect on soil fertility has 

 become an interesting subject for investigation. 



Vanillin has been reported in the seeds and roots of oats, 2 seeds of 

 white lupine, 3 asparagus shoots, 4 in raw-beet sugar, 5 and in the leaves 

 and roots of a number of other plants. It has recently been reported 

 to occur in rotten oak wood, in pineapples, in lawn grass, in ungermi- 

 nated wheat, in wheat bran, in the roots, tops, and seeds of wheat 

 seedlings, and in water in which wheat seedlings grew. 6 Its presence 

 in wood and various forms of vegetation has led to the conclusion that 

 vanillin in soils has its origin in vegetable debris. 



Vanillin has the characteristics of an aldehyde, and, like the salicylic 

 aldehyde already reported, 7 is toxic to plants, though to a less degree. 



T, E. C, J. Agr. Res. 1, 357 (1914). 

 « de Routon, Compt. rend., 125, 797 (1897). 



* Campani and Grimaldi, Chem. Centr., 1, 377 (1888). 



* Von Lippmann, Ber. Chem. Ges., 18, 3335 (1885). 



s Scheibler, Ber. Chem. Ges., 13, 335 (1880) Lippmann, ibid,, 662. 

 6 Sullivan, M. X., Jour. Indus, and Eng. Chem., 6, 119 (1914). 



* Schreiner, O., and Skinner, J. J., Bui. 108, U. S. Department of Agriculture, 1914. 



Note. — The effect upon plant growth of vanillin, a toxic soil constituent, as demonstrated in pot experi- 

 ments and field tests, is described in this bulletin. 

 67216°— 15 



