Page 104 - E-BOOK English
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The representatives of Leptosols in Thailand
Skeletic Leptosols
Skeletic Leptosols have coarse fragments
averaged ≥ 40% (by volume) over a depth of 100
cm from the surface soil or to continuous rock,
technic hard material or a cemented or indurated
layer, whichever is shallower.
Huai Yot series (Ho) is a representative of
Skeletic Leptosols. Huai Yot soils are derived from
fine grain clastic rocks namely shale, phyllite or
equivalent rocks and occurr on denudation surface.
They usually occurr on an eroded hill. They are
mostly found on steep sloping areas of the north,
central, and south of Thailand. Relief is undulating
to hilly with slopes ranging from 5-35 percent.
Drainage is well drained. Permeability is estimated
to be rapid. Surface runoff is rapid and soils are very
susceptible to erosion. They are very shallow soils
to bed rocks and characterized by a brown or dark
yellowish brown loam surface or A horizon overlying
a strong brown and/or yellowish brown very gravelly
loam or very gravelly clay loam which in turn overlies
a layer of bed rock within 50 cm from the surface
soil. Soil pH is very strongly acid to strongly acid
(pH 4.5-5.5) throughout the soil profile. Shallow to
bedrock is the main constraint for rice production.
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