I am very pleased that “Studies of Land Classification” has been discussed with much interest among agricultural researchers over the last 10 years. Especially Prof. NAGASAKI and KITAMURA's book titled “Studies of Land Classification” published by University of Tokyo is informative on this subject. I would like to comment on this research field in the light of my own experience.
Following my experience, it is not so meaningful to seek the single aim and single method of analizing land classification research. “Land Classification” itself has a very broad meaning and we can approach it from many directions. So if we seek a single and integrated aim and method, we will lose the real and important results of land classification studies. The important thing might be that researchers of land classification should know clearly that every research field has its own aim. At the biginning of land classification research there is an aim, not a method.
Many discussions appear in this book concerning economic land classification, and I expect some may have reservations about economic land classification. As I write in this paper, at one glance, economic land classification cannot be thought as the category of land classification which many land scientists think it to be. Economic land classification has its own special history in U.S.A. But, I understand its ultimate aim is the interpretation of concept and component of land productivity in perms of economics in soil science.