Orders: Organic - Subgroups
Subgroup |
Great Group |
|||
Fibrisol |
Mesisol |
Humisol |
Folisol |
|
Typic |
X |
X |
X |
Not applicable |
| Fibric | Not applicable |
X |
X |
Not applicable |
Mesic |
X |
Not applicable |
X |
Not applicable |
Humic |
X |
X |
Not applicable |
X |
Limnic |
X |
X |
X |
Not applicable |
Cumulic |
X |
X |
X |
Not applicable |
Terric |
X |
X |
X |
Not applicable |
Terric Fibric |
Not applicable |
X |
X |
Not applicable |
Terric Mesic |
X |
Not applicable |
X |
Not applicable |
Terric Humic |
X |
X |
Not applicable |
Not applicable |
Hydric |
X |
X |
X |
Not applicable |
Hemic |
Not applicable |
Not applicable |
Not applicable |
X |
Lignic |
Not applicable |
Not applicable |
Not applicable |
X |
Histic |
Not applicable |
Not applicable |
Not applicable |
X |
Typic subgroup
Soils of the Typic subgroup do not have any of the horizons discussed below.
Fibric subgroup
Soils of the Fibric subgroup have a subdominant fibric layer thicker than 25 cm in the middle or bottom tiers.
Mesic subgroup
These soils have a subdominant mesic layer thicker than 25 cm in the middle or bottom tiers.
Humic subgroup
These soils have a subdominant humic layer thicker than 25 cm in the middle or bottom tiers.
Terric subgroup (Terric Mesisol 2)
Soils of these subgroups have a contact with a mineral horizon within the depths specified by the depth relationship diagram. The Terric prefix can also be used before Fibric, Mesic, or Humic suffixes for soils that meet both sets of criteria.
Limnic subgroup
These soils have a limnic layer beneath the surface tier.
Cumulic subgroup
These soils have either multiple layers of mineral material (pond or alluvial sediments) that together are more than 5 cm thick or on layers 5 to 30 cm thick.
Hydric subgroup
These soils have a layer of water that extends from a depth of not less than 40 cm to a depth of more than 1.6 m.
The final four subgroups are only found in the Folisol great group.
Hemic subgroup
Soils of this subgroup are composed dominantly of the moderately decomposed F horizon in the control section and may have subdominant H and O horizons, each less than 10 cm thick.
Humic subgroup
Soils of this subgroup are composed dominantly of the well-decomposed H horizon in the control section and may have subdominant F and O horizons each less than 10 cm thick.
Lignic subgroup
Soils of this subgroup are dominated by F or H horizons composed primarily of moderately to well-decomposed woody materials. These materials occupy more than 30% of the surface area of the F and H horizons. The decaying wood that makes up the F and H horizons generally consists of fallen trees. (Organic Vegetation)
Histic subgroup
Soils of this subgroup are dominated by F or H horizons and are directly underlain by a O horizon greater than 10 cm.
