Abstract
Soils from the tea farms in Siduoka Prefecture which belong to various soil system were investigated as to their exchangeable acidity (after DAIKUHARA), pH (by quinhydrone) and Mn content (by colorimetric method of WILLARD and GREATHOUSE, 1917) and found : (1) The highest and lowest exchangeable acidity were 174.6 and 0 respcctively ; (2) pH ranged 3.80-6.0 and mostly 4.5 ± ; (3) Quantity of Mn varied from trace to 2.5% (Mn_2O_3) and generally 0.1-0.8% with a few exception ; (4) No definite correlation between the acidity and Mn content was fonnd ; (5) Neither direct qualitative nor quantitative relation between the tea crop and the acidity was noted so far as this investigation is concerned.
