158 SOIL 



Waksman, S. a., and Iyer, K. R. N.: Contribution to Our Knowledge of the 

 Chemical Nature and Origin of Humus: IV. Fixation of Proteins by Lignins 

 and Formation of Complexes Resistant to Microbial Decomposition, Soil 

 Science, pp. 69-82, 1933. 



Wherry, Edgar T. : Observations on the Soil Acidity of Ericaceae and Asso- 

 ciated Plants in the Middle Atlantic States, Proc. Acad. Nat. Sci., Phila- 

 delphia, 72, 84-111, 1920. 



Soil Acidity and a Field Method for Its Measurement, Ecology, 1, 



160-173, 1920. 



■The Soil Reactions of the Ferns of Woods and Swamps, Am. Fern 



Jour., 11, 5-6, 1921. 



Wilde, S. A.: The Relation of Soils and Forest Vegetation in the Lake States 

 Region, Ecology, 14, 94-105, 1933. 



Soil Reaction in Relation to Forestry and Its Determination by Sim- 

 ple Tests, Jour. For., 32, 411-418, 1934. 



