108 Keys to Soil Taxonomy
for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Xerertic Calciargids GEEC. Other Calciargids that have both:
1. One or both of the following:
a. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Ustertic Calciargids GEED. Other Calciargids that have one or both of the following:
1. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or
2. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower.
Vertic Calciargids GEEE. Other Calciargids that are either:
1. Irrigated and have aquic conditions for some time in normal years in one or more layers within 100 cm of the soil surface; or
2. Saturated with water in one or more layers within 100 cm of the soil surface for 1 month or more in normal years.
Aquic Calciargids
GEEF. Other Calciargids that:
1. Have a texture class (fine-earth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the soil surface to the top of an argillic horizon at a depth of 50 cm or more;
and
2. Have a moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Arenic Ustic Calciargids GEEG. Other Calciargids that have a texture class (fine-earth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the soil surface to the top of an argillic horizon at a depth of 50 cm or more.
Arenic Calciargids GEEH. Other Calciargids that have both:
1. One or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) durinodes or are brittle and have at least a firm rupture-resistance class when moist; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Durinodic Xeric Calciargids GEEI. Other Calciargids that have one or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) durinodes or are brittle and have at least a firm rupture-resistance class when moist.
Durinodic Calciargids GEEJ. Other Calciargids that have both:
1. One or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) nodules or concretions; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Petronodic Xeric Calciargids
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GEEK. Other Calciargids that have both:
1. One or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) nodules or concretions; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Petronodic Ustic Calciargids GEEL. Other Calciargids that have one or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) nodules or concretions.
Petronodic Calciargids GEEM. Other Calciargids that have both:
1. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric; and
2. Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
a. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
b. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrixerandic Calciargids GEEN. Other Calciargids that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
1. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
2. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrandic Calciargids
GEEO. Other Calciargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on xeric.
Xeric Calciargids GEEP. Other Calciargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on ustic.
Ustic Calciargids GEEQ. Other Calciargids.
Typic Calciargids
Gypsiargids
Key to Subgroups
GEDA. Gypsiargids that are either:
1. Irrigated and have aquic conditions for some time in normal years in one or more layers within 100 cm of the soil surface; or
2. Are saturated with water in one or more layers within 100 cm of the soil surface for 1 month or more in normal years.
Aquic Gypsiargids GEDB. Other Gypsiargids that have one or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that either contain 20 percent or more (by volume) durinodes or are brittle and have at least a firm rupture-resistance class when moist.
Durinodic Gypsiargids GEDC. Other Gypsiargids that have both:
1. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric; and
2. Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
a. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
b. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent
110 Keys to Soil Taxonomy
or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrixerandic Gypsiargids GEDD. Other Gypsiargids that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
1. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
2. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrandic Gypsiargids GEDE. Other Gypsiargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on xeric.
Xeric Gypsiargids GEDF. Other Gypsiargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on ustic.
Ustic Gypsiargids GEDG. Other Gypsiargids.
Typic Gypsiargids
Haplargids
Key to Subgroups
GEFA. Haplargids that have both:
1. A lithic contact within 50 cm of the soil surface; and 2. An argillic horizon that is discontinuous throughout each pedon.
Lithic Ruptic-Entic Haplargids GEFB. Other Haplargids that have both:
1. A lithic contact within 50 cm of the soil surface; and 2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the
soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Lithic Xeric Haplargids GEFC. Other Haplargids that have both:
1. A lithic contact within 50 cm of the soil surface; and 2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Lithic Ustic Haplargids GEFD. Other Haplargids that have a lithic contact within 50 cm of the soil surface.
Lithic Haplargids GEFE. Other Haplargids that have both:
1. One or both of the following:
a. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Xerertic Haplargids GEFF. Other Haplargids that have both:
1. One or both of the following:
a. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface;
or
b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the
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soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Ustertic Haplargids GEFG. Other Haplargids that have one or both of the
following:
1. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or
2. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact if shallower.
Vertic Haplargids GEFH. Other Haplargids that are either:
1. Irrigated and have aquic conditions for some time in normal years in one or more layers within 100 cm of the soil surface; or
2. Saturated with water in one or more layers within 100 cm of the soil surface for 1 month or more in normal years.
Aquic Haplargids GEFI. Other Haplargids that:
1. Have a texture class (fine-earth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the soil surface to the top of an argillic horizon at a depth of 50 cm or more;
and
2. Have a moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Arenic Ustic Haplargids GEFJ. Other Haplargids that have a texture class (fine-earth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the soil surface to the top of an argillic horizon at a depth of 50 cm or more.
Arenic Haplargids GEFK. Other Haplargids that have both:
1. One or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) durinodes or are brittle and have at least a firm rupture-resistance class when moist; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Durinodic Xeric Haplargids GEFL. Other Haplargids that have one or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) durinodes or are brittle and have at least a firm rupture-resistance class when moist.
Durinodic Haplargids GEFM. Other Haplargids that have both:
1. One or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) nodules or concretions; and
2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Petronodic Ustic Haplargids GEFN. Other Haplargids that have one or more horizons, within 100 cm of the soil surface and with a combined thickness of 15 cm or more, that contain 20 percent or more (by volume) nodules or concretions.
Petronodic Haplargids GEFO. Other Haplargids that have both:
1. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric; and
2. Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
a. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
b. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrixerandic Haplargids
112 Keys to Soil Taxonomy
GEFP. Other Haplargids that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the soil surface, one or both of the following:
1. More than 35 percent (by volume) particles 2.0 mm or larger in diameter, of which more than 66 percent is cinders, pumice, and pumicelike fragments; or
2. A fine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter, of which 5 percent or more is volcanic glass, and [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is 30 or more.
Vitrandic Haplargids GEFQ. Other Haplargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on xeric.
Xeric Haplargids GEFR. Other Haplargids that, in normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on ustic.
Ustic Haplargids GEFS. Other Haplargids.
Typic Haplargids
Natrargids
Key to Subgroups
GEBA. Natrargids that have both:
1. A lithic contact within 50 cm of the soil surface; and 2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on xeric.
Lithic Xeric Natrargids GEBB. Other Natrargids that have both:
1. A lithic contact within 50 cm of the soil surface; and 2. A moisture control section that, in normal years, is dry in all parts for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and a soil moisture regime that borders on ustic.
Lithic Ustic Natrargids
GEBC. Other Natrargids that have a lithic contact within 50 cm of the soil surface.
Lithic Natrargids GEBD. Other Natrargids that:
1. In normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on xeric; and
2. Have one or both of the following:
a. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in most years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact, whichever is shallower.
Xerertic Natrargids GEBE. Other Natrargids that:
1. In normal years, are dry in all parts of the moisture control section for less than three-fourths of the time (cumulative) when the soil temperature at a depth of 50 cm below the soil surface is 5 oC or higher and have a soil moisture regime that borders on ustic; and
2. Have one or both of the following:
a. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in most years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or b. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact, whichever is shallower.
Ustertic Natrargids GEBF. Other Natrargids that have one or both of the
following:
1. Cracks within 125 cm of the soil surface that are 5 mm or more wide through a thickness of 30 cm or more for some time in normal years and slickensides or wedge-shaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the soil surface; or
2. A linear extensibility of 6.0 cm or more between the soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact, whichever is shallower.
Vertic Natrargids