In the Tsugaru and the Shimokita Peninsulas, the growth of "Hiba" (Thujopsis dolabrata var. Hondai Makino) is very vigorous, and various podozolized soils are found in the "Hiba" natural forests. These podsolized soils are classified into two types; biased dried type and biased wetted type. In this report, morphology and properties of typical soils of two types were described, and genesis of those soils were discussed. From the analytical data of two soils, it is found that leaching and accumulation of mechanical and chemical substances is clearly recognized. The writer believes that the formation of podzolized soil in the "Hiba" natural forest is due to acid humus derived from the fallen leaves of "Hiba". Moreover, judging from the distribution of humic acid, alumina and magnesium in profiles, it is presumed that vertical leaching in the dried sandy soil dominates than that in the wetted clayey one.
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