Agriculture Reference
In-Depth Information
SOIL ORDERS IN CSTC
Keys to Soil Orders
A. Soils that:
¤ Do not have andic soil properties in 60% or more of the thickness between the soil surface and
either a depth of 60 cm, or a lithic or paralithic contact if shallower
¤Have organic soil materials that meet one or more of the following:
¤O erlie cindery, fragmental, or pumiceous materials and/or Ýll their interstices, and directly
below these materials either a lithic or paralithic contact
¤
When added with underlying cindery, fragmental, or pumiceous materials, total 40 cm or more
between the soil surface and a depth of 50 cm
¤
Constitute two thirds or more of the total thickness of the soil to a lithic or paralithic contact,
and minerals soils which, if present, have a total thickness of 10 cm or less
¤
Are saturated with water for 6 months or more per year in most years (or artiÝcially drained),
have an upper boundary within 40 cm of the soil surface, and have a total thickness of either
¤
60 cm or more if three fourths or more of their volume consists of moss, or if their bulk
density, moist, is less than 0.1 Mg/m
3
¤
40 cm or more if they consist either of sapric or hemic materials, or of Ýbric materials
with less than three fourths (by volume) moss Ýbers and a bulk density, moist, of 0.1Ï0.4
Mg/m
3
Histosols
B. Other soils that have the following combination of horizons:
¤Have an anthrostagnic epipedon and hydragric horizon
¤Have a Ýmic epipedon and phos-agric horizon
¤Have a siltigic epipedon or cumulic epipedon
Anthrosols
C. Other soils that do not have anthropic epipedon and do not have argic horizon
above a spodic horizon, but have:
¤A spodic horizon that has its upper boundary within 100 cm of the minerals soil surface
¤
No andic property in 60% or more of the thickness either
¤Within 60 cm either of the minerals soil surface, or of the top of an organic layer with andic
property, whichever is shallower, if there is no lithic or paralithic contact within that depth
¤
Between the minerals soil surface, or the top of an organic layer with andic properties, whichever
is shallower, and a lithic or paralithic contact that is present within 60 cm either of the mineral
soil surface or of the top of an organic layer with andic property, whichever is shallower
Spodosols
D. Other soils that have andic soil property in 60% or more of the thickness either
¤Within 60 cm either of the mineral soil surface, or of the top of an organic layer with andic
property, whichever is shallower, if there is no lithic or paralithic contact, within that depth
¤
Between the minerals soil surface, or the top of an organic layer with andic properties, whichever
is shallower, and a lithic or paralithic contact that is present within 60 cm either of the mineral
soil surface or of the top of an organic layer with andic property, whichever is shallower
