ly] LANDSCAPES AND VEGETATION 561 



than any measurement of individual ones, but it commonly provides 

 the most reliable ecological basis for any agricultural, forestral, or 

 allied planning. 



Further CoNsmERATiON 



Almost any modern work on general physical geography or geology 

 will have some treatment of landforms as such, though the approaches 

 and classification may vary greatly in diiTerent works. A useful account, 

 largely along the lines followed in the present chapter, is to be found in 

 Henry D. Thompson's Fundamentals of Earth Science (Appleton-Century- 

 Crofts, New York, pp. xiii + 461, 1947). As for the usually far wider, 

 constructional landforms that were deemed to be too variable or, alterna- 

 tively, too general for useful consideration in any detail here, the mountain 

 ones are well treated in R. Peattie's Mountain Geography (Harvard 

 University Press, Cambridge, Mass., pp. xiv + 257, 1936) and the plains 

 and plateaux in M. D. Haviland's Forest, Steppe and Tundra (Cambridge 

 University Press, Cambridge, Eng., pp. [xi] -f 218, 1926). 



For further details about land utilization, including many botanical 

 aspects, reference may be made to Edward H. Graham's Natural Principles 

 of Land Use (Oxford University Press, London etc., pp. xiii + 274, 1944). 

 This gives an extensive and valuable annotated bibliography from which 

 any interested reader may select further works to his taste. A very 

 readable introductory book is Paul B. Sears's Life and Environment 

 (Teachers College, Columbia University, New York, pp. xx -j- 175, 1939). 



