The Physical Characteristics of the Tea Garden Soil (Part 2)

Abstract

As YODER'S method was not available to analyze the soil aggregate of the Makinohara diluvial upland soils, the method was modified as follows :The dry sieving apparatus has 2 sieves (6 and 2.5mm.), and the wet sieving apparatus consists of 4 sets of 4 sieves (2, 1. 0.5 and 0.1 mm.), the latter is operated for 60 min., with 6 cm. of amplitude and 20 reciprocations per min.By above-mentioned method, the aggregate was analyzed of the Makinohara brown soil and "Kuroboku" sampled from an uncultivated land as well as from a tea garden.The soil mass and the soil aggregate were perfectly separated and determined by wet sieving of the residual finer part after dry sieving of 2.5 mm.The aggregate thus determined was water-stable and indicated the physical structure of the Makinohara diluvial soils clearly.