In this paper, the morphological and chemical properties of four profiles of forest soil in forest area on basalt plateau in northern Corea, are discussed. The elevation of plateau is between 1000 and 1100 meters above sea level. The respective profiles lie in the vicinity of lat. 41°31'N. and long. 128°19'E. The surface of this plateau are covered with volcanic ash and sand in varying thickness from several to thirty centimeters. On basing the forest stock and other facts, Prof. T. NAKAI, a botanist, estimated the age of this volcanic eruption must be 250〜300 years ago. The forest consist mainly of picea, and mix some larix and betula. The climate is very humid and the mean annual values record ; temperature 1.1℃, precipitation 837 mm and humidity 71%. Therefore, the present profiles are the resultant of such soil forming conditions. Some analytical data on fine soil of one profile are given in the following two tables.[table][table]The data in above tables indicate a fairly advanced state of podzolizauion, and all horizons show fairly high acidity and low calcium saturation. Acidity decreases with depth and harmonizing with this, the calcium saturation increases with depth. The degree of podzolization differs in different places.

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Shizuoka prefecture is one of the chief districts of citrus production in Japan. Author studied the soil profiles of citrus orchard in this district and the results are summarized as follows. 1. Nomenclature from the result of mechanical analysis is mostly fine clay or fine clayey loam. 2. SiO_2-Al_2O_3 ratio of clay fraction is, with some exception, about 2.5. 3. Nitrogen and humus contents are scanty in surface soil (N 0.224〜0.118% and humus 4.862〜2.108%), and much less in deeper horizon. C-N ratio is 10〜9 in general, and 12〜14 exceptionally in Izu district. Content of available phosphorus is low even in surface soil (P_2O_5 0.0281〜0.0031% soluble in 1/5 N HCl), still less in deeper horizon. On the other hand, content of available potash is sufficient (K_2O 0.133〜0.026%). 4. pH value is mostly 5〜6. Exchangeable base is scanty contained (S=20.66〜10.29 m. e./100g surface soil), and Mg increases with depth. Saturation degree is also low.

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