Solod (SO)

Besides an Ae horizon, the soils of this great group have an AB or BA horizon, which appears to have developed through degradation of the upper part of a former solonetzic B horizon. Both the Ae and AB horizons are usually platy. The upper boundary of the solonetzic B horizon is gradual and usually at greater depth than the B horizon of the associated Solonetzs and Solodized Solonetzs. The solonetzic B horizon commonly does not have strong columnar structure and usually breaks to blocky peds that are hard to very hard when dry. Clay skins are common to frequent in the B horizon. The Cs or Csa horizon commonly occurs below a Cca or Ck horizon.

Solods have a distinct Ae horizon at least 2 cm thick, an AB or BA horizon at least 5 cm thick, and a solonetzic B horizon. The great group is divided into eight subgroups.

Brown Solod (B.SO)

Common horizon sequence: Ah, Ae, AB, Bnt, Ck, Csk

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They are associated with grass and forb vegetation and a subarid to semiarid climate. In areas of these soils there is commonly evidence of previously eroded pits, but they are usually shallow and grass covered.


Brown Solods have an Ah, Ahe, or Ap horizon with color values higher than 4.5 dry and chromas usually higher than 1.5 dry. They have Ae, AB or BA, and solonetzic B horizons as specified for the great group. They do not have faint to distinct mottles that indicate gleying within the upper 50 cm.

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Dark Brown Solod (DB.SO)

Common horizon sequence: Ahe, Ae, AB, Bnt, Ck, Csk

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They are associated with mesophytic grasses and forbs in a semiarid to subhumid climate. Evidence of former eroded pits is common in areas of these soils, but the depressions are shallow and grass covered.

Dark Brown Solods have an Ah, Ahe or Ap horizon with color values lower than 3.5 moist and 3.5-4.5 dry and chromas usually higher than 1.5 dry. They have Ae, AB or BA, and solonetzic B horizons as specified for the great group. They do not have faint to distinct mottles that indicate gleying within the upper 50 cm.

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Black Solod (BL.SO)

Common horizon sequence: Ahe, Ae, AB, Bnt, Ck, Csk

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They are associated mainly with mesophytic grasses and forbs in a subhumid climate, but they also occur in areas of thin or discontinuous shrub and tree cover.

Black Solods have an Ah, Ahe, or Ap horizon with color values lower than 3.5 dry and chromas usually higher than 1.5 dry. They have Ae, AB or BA, and solonetzic B horizons as specified for the great group. They do not have faint to distinct mottles that indicate gleying within the upper 50 cm.

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Dark Gray Solod (DG.SO)

Common horizon sequence: Ahe, Ae, AB, Bnt, Ck, Csk

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They are associated with forest, shrub, and grass vegetation, a subhumid climate, and Eluviated Black Chernozems or Dark Gray Luvisols developed in materials of lower salinity.

Dark Gray Solods have an Ah, Ahe or Ap horizon with color values of 3.5-4.5 dry and chromas usually lower than 2 moist or dry. They have Ae, AB, and solonetzic B horizons as specified for the great group. They do not have faint to distinct mottles that indicate gleying within the upper 50 cm.

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Gray Solod (G.SO)

Common horizon sequence: Ahe, Ae, AB, Bnt, Ck, Csk

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They are associated with forest vegetation, a subhumid climate, and Dark Gray Luvisols developed in materials of lower salinity.

Gray Solods have an Ahe, Ae or Ap horizon with color values higher than 4.5 dry and chromas usually lower than 2 dry. They have Ae, AB or BA, and solonetzic B horizons as specified for the great group. They do not have faint to distinct mottles that indicate gleying within the upper 50 cm.

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Gleyed Brown Solod (GLB.SO)

Common horizon sequence: Ah, Aegj, ABgj, Bntgj, Cskg

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They differ from Brown Solods by having faint to distinct mottles that indicate gleying within 50 cm of the mineral surface.

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Gleyed Dark Brown Solod (GLDB.SO)

Common horizon sequence: Ah, Aegj, ABgj, Bntgj, Cskg

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They differ from Dark Brown Solods by having faint to distinct mottles that indicate gleying within 50 cm of the mineral surface.

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Gleyed Black Solod (GLBL.SO)

Common horizon sequence: Ah, Aegj, ABgj, Bntgj, Cskg

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They differ from Black Solods by having faint to distinct mottles that indicate gleying within 50 cm of the mineral surface.

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Gleyed Dark Gray Solod (GLDG.SO)

Common horizon sequence: Ahe, Aegj, ABgj, Bntgj, Cskg

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They differ from Dark Gray Solods by having faint to distinct mottles that indicate gleying within 50 cm of the mineral surface.

List all known examples

Gleyed Gray Solod (GLG.SO)

Common horizon sequence: Ahe, Aegj, ABgj, Bntgj, Cskg

Soils of this subgroup have a solonetzic B horizon as defined for the Solonetzic order and the properties specified for the Solod great group. They differ from Gray Solods by having faint to distinct mottles that indicate gleying within 50 cm of the mineral surface.

List all known examples

Note: Diagnostic horizons are underlined.