Bui. 164, U. S. Dept. of Agriculture. 



Plate II 



Fig. 1.— Effect of Vanillin on Wheat in Florida Sand. 



(Xo. 1, Soil ■untreated; No. 2, vanillin 100 p. p. m.: Xo. 3, vanillin -200 p. p. m.; No. 4, vanillin 

 300 p. p. m.; No. 5, vanillin 400 p. p. m.; No. 6, vanillin 500 p. p. m.) 



Fig. 2.— Effect of Vanillin on Wheat in Susquehanna Sandy Loam. 



(No. 1, Soil untreated: No. 2, vanillin 100 p. p. m.: No. 3. vanillin 200 p. p.m., No. 4, vanillin 

 300 p. p. m.; No. 5, vanillin 100 p. p. m.; No. 6 vanillin 500 p. p. m.) 



Fig. 3.— Effect of Vanillin on Wheat in Hagerstown Loam. 



(Xo. 1, Soil untreated; No. 2, vanillin 100 p. p. m.; Xo. 3, vanillin 200 p. p. m.: Xo. 4, vanillin 

 300 p. p. m.; Xo. 5, vanillin 400 p. p. m.; Xo. 6, vanillin 500 p. p. m.) 



