Chapter 3: Key to Soil Great Groups

A. Cryosolic order

AA. Cryosolic soils that are formed primarily in organic materials and have permafrost within 1 m of the surface… Organic Cryosol

AB. Other Cryosolic soils that are formed in mineral materials, have marked evidence of cryoturbation, and have permafrost within 2 m of the surface… Turbic Cryosol

AC. Other Cryosolic soils that are formed in mineral materials, do not have marked evidence of cryoturbation, and have permafrost within 1 m of the surface… Static Cryosol

B. Organic order

BA. Organic soils that are formed primarily in upland organic (folic) materials, generally of forest origin, and are rarely saturated with water… Folisol

BB. Other Organic soils that are formed in relatively undecomposed organic materials and have a dominantly fibric middle tier… Fibrisol

BC. Other Organic soils that are formed in organic materials, are in an intermediate stage of decomposition, and have a dominantly mesic middle tier… Mesisol

BD. Other Organic soils that are formed in organic materials, are in an advanced stage of decomposition, and have a dominantly humic middle tier… Humisol

C. Vertisolic order

CA. Vertisolic soils that have either a surface color value of ≥3.5 dry if well to imperfectly drained or an Ah horizon <10 cm in thickness if poorly drained… Vertisol

CB. Other Vertisolic soils that have either a surface color value of <3.5 dry if well to imperfectly drained or an Ah horizon ≥10 cm in thickness if poorly drained… Humic Vertisol

D. Podzolic order

DA. Podzolic soils that have a Bh horizon ≥10 cm in thickness… Humic Podzol

DB. Other Podzolic soils that have a Bhf horizon ≥10 cm in thickness… Ferro-Humic Podzol

DC. Other Podzolic soils… Humo-Ferric Podzol

E. Gleysolic order

EA. Gleysolic soils that have a Btg horizon and usually have an eluvial horizon … Luvic Gleysol

EB. Other Gleysolic soils that have either an Ah horizon ≥10 cm in thickness or an Ap horizon ≥15 cm in thickness and have at least 2.0% organic C in the surface horizon… Humic Gleysol

EC. Other Gleysolic soils… Gleysol

F. Solonetzic order

FA. Solonetzic soils that have a slickenside horizon within 1 m of the mineral surface… Vertic Solonetz

FB. Other Solonetzic soils that have an Ae horizon 2 cm in thickness with a distinct AB or BA horizon (disintegrating Bnt)… Solod

FC. Other Solonetzic soils that have an Ae horizon ≥2 cm in thickness . . . Solodized Solonetz

FD. Other Solonetzic soils… Solonetz

G. Chernozemic order

GA. Chernozemic soils that have a surface color value of 4.5-5.5 dry and a chroma usually >1.5 dry… Brown Chernozem

GB. Other Chernozemic soils that have a surface color value of 3.5-4.5 dry and a chroma usually >1.5 dry… Dark Brown Chernozem

GC. Other Chernozemic soils that have a surface color value of <3.5 dry and a chroma usually ≤1.5 dry… Black Chernozem

GD. Other Chernozemic soils that have a surface color value of 3.5-4.5 (3.5-5.0 for Ap) dry, a chroma usually ≤1.5 dry, and characteristics indicating eluviation associated with soils formed under forest vegetation… Dark Gray Chernozem

H. Luvisolic order

HA. Luvisolic soils that have a forest mull Ah horizon and a mean annual soil temperature ≥8°C… Gray Brown Luvisol

HB. Other Luvisolic soils… Gray Luvisol

I. Brunisolic order

IA. Brunisolic soils that have an Ah or Ap horizon ≥10 cm in thickness and pH of ≥5.5 (0.01 M CaCl2)… Melanic Brunisol

IB. Other Brunisolic soils that have either no Ah horizon or an Ah (or Ap) horizon <10 cm in thickness and pH of ≥5.5 (0.01 M CaCl2)… Eutric Brunisol

IC. Brunisolic soils that have an Ah or Ap horizon ≥10 cm in thickness and pH of <5.5 (0.01 M CaCl2)… Sombric Brunisol

ID. Other Brunisolic soils that have no Ah horizon or an Ah (or Ap) <10 cm in thickness and pH of <5.5 (0.01 M CaCl2)… Dystric Brunisol

J. Regosolic order

JA. Regosolic soils that have an Ah or Ap horizon ≥10 cm in thickness… Humic Regosol

JB. Other Regosolic soils… Regosol

Source : The Canadian System of Soil Classification (Third Edition)

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