Ключи к почвенной таксономии 2014

HCF.  Other Udults that have both of the following:

1.  An epipedon that has a color value, moist, of 3 or less throughout; and

2.  In all subhorizons in the upper 100 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 100 cm thick, more than 50 percent colors that have all of the following:

value.

Rhodudults, p. 298

HCG.  Other Udults.

Hapludults, p. 291

Fragiudults

Key to Subgroups

HCBA.  Fragiudults 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 mineral soil surface to the top of an argillic or kandic horizon at a depth of 50 to 100 cm.

Arenic Fragiudults

HCBB.  Other Fragiudults that have both of the following:

1.  In one or more horizons within 40 cm of the mineral soil surface, redox depletions with chroma of 2 or less and also aquic conditions for some time in normal years (or artificial drainage); and

2.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthaquic Fragiudults

HCBC.  Other Fragiudults that have both: 1.  One or more of the following:

horizon that has clay films on both vertical and horizontal surfaces of any peds; or

c.  Between the argillic or kandic horizon and the fragipan, have one or more horizons with 50 percent or more chroma of 3 or less and with a clay content 3

percent or more (absolute, in the fine-earth fraction) lower than that in both the argillic or kandic horizon and the fragipan; and

2.  In one or more horizons within 40 cm of the mineral soil

surface, redox depletions with chroma of 2 or less and also aquic conditions for some time in normal years (or artificial drainage).

Glossaquic Fragiudults

HCBD.  Other Fragiudults that have, in one or more subhorizons above the fragipan and within the upper 25 cm of the argillic or kandic horizon, redox depletions with chroma of 2 or less and also aquic conditions for some time in normal years (or artificial drainage).

Aquic Fragiudults

HCBE.  Other Fragiudults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Fragiudults

HCBF.  Other Fragiudults that meet one or more of the following:

1.  Have a glossic horizon above the fragipan; or

2.  Do not have, above the fragipan, an argillic or kandic horizon that has clay films on both vertical and horizontal surfaces of any peds; or

3.  Between the argillic or kandic horizon and the fragipan, have one or more horizons with 50 percent or more chroma of 3 or less and with a clay content 3 percent or more

(absolute, in the fine-earth fraction) lower than that in both the argillic or kandic horizon and the fragipan.

Glossic Fragiudults

HCBG.  Other Fragiudults that have a color value, moist, of 3 or less and a color value, dry, of 5 or less (crushed and smoothed sample) in either:

1.  An Ap horizon that is 18 cm or more thick; or

2.  The surface layer after mixing of the upper 18 cm.

Humic Fragiudults

HCBH.  Other Fragiudults.

Typic Fragiudults

Hapludults

Key to Subgroups

HCGA.  Hapludults that have either or both:

1.  In each pedon, a discontinuous lithic contact within 50 cm of the mineral soil surface; and

2.  In each pedon, a discontinuous argillic horizon that is interrupted by ledges of bedrock.

Lithic-Ruptic-Entic Hapludults

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following:

1.  Cracks within 125 cm of the mineral 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 wedgeshaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the mineral soil surface; or

2.  Alinear extensibility of 6.0 cm or more between the mineral soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact, whichever is shallower.

Vertic Hapludults

HCGD.  Other Hapludults that have both of the following: 1.  Fragic soil properties either:

a.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

b.  In 60 percent or more of the volume of a layer 15 cm or more thick; and

2.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Fragiaquic Hapludults

HCGE.  Other Hapludults 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 mineral soil surface to the top of an argillic horizon at a depth of 50 to 100 cm; and

2.  Have, in one or more subhorizons within the upper

60 cm of the argillic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Arenic Hapludults

HCGF.  Other Hapludults that have, in one or more subhorizons within the upper 60 cm of the argillic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Hapludults

HCGG.  Other Hapludults that have fragic soil properties either:

1.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

2.  In 60 percent or more of the volume of a layer 15 cm or more thick.

Fragic Hapludults

HCGH.  Other Hapludults that in normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

1.  20 or more consecutive days; or

2.  30 or more cumulative days.

Oxyaquic Hapludults

HCGI.  Other Hapludults that have an argillic horizon that:

1.  Consists entirely of lamellae; or

2.  Is a combination of two or more lamellae and one or more subhorizons with a thickness of 7.5 to 20 cm, each layer with an overlying eluvial horizon; or

3.  Consists of one or more subhorizons that are more than 20 cm thick, each with an overlying eluvial horizon, and above these horizons there are either:

throughout the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick.

Psammentic Hapludults

HCGK.  Other Hapludults 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 mineral soil surface to the top of an argillic horizon at a depth of 50 to 100 cm.

Arenic Hapludults

HCGL.  Other Hapludults 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 mineral soil surface to the top of an argillic horizon at a depth of 100 cm or more.

Grossarenic Hapludults

HCGM.  Other Hapludults that:

1.  Do not have a densic, lithic, or paralithic contact within 50 cm of the mineral soil surface; and

2.  Have an argillic horizon that is 25 cm or less thick.

Inceptic Hapludults

HCGN.  Other Hapludults that have a color value, moist, of 3 or less and a color value, dry, of 5 or less (crushed and smoothed sample) in either:

1.  An Ap horizon that is 18 cm or more thick; or

2.  The surface layer after mixing of the upper 18 cm.

Humic Hapludults

HCGO.  Other Hapludults.

Typic Hapludults

Kandiudults

Key to Subgroups

HCCA.  Kandiudults that have all of the following:

1.  Atexture 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm; and

2.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface; and

3.  In one or more layers either within 75 cm of the mineral soil surface or, if the chroma throughout the upper 75 cm results from uncoated sand grains, within the upper 12.5 cm of the kandic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Arenic Plinthaquic Kandiudults

HCCB.  Other Kandiudults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm; and

2.  Have, in one or more layers either within 75 cm of the mineral soil surface or, if the chroma throughout the upper 75 cm results from uncoated sand grains, within the upper 12.5 cm of the kandic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and

aquic conditions for some time in normal years (or artificial drainage).

Aquic Arenic Kandiudults

HCCC.  Other Kandiudults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Arenic Plinthic Kandiudults

HCCD.  Other Kandiudults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm; and

2.  Have, in all subhorizons in the upper 75 cm of the kandic horizon or throughout the entire kandic horizon if it is less than 75 cm thick, more than 50 percent colors that have all of the following:

fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm.

Arenic Kandiudults

HCCF.  Other Kandiudults 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 mineral soil surface to the top of a kandic horizon at a depth of 100 cm or more; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Grossarenic Plinthic Kandiudults

HCCG.  Other Kandiudults 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

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from the mineral soil surface to the top of a kandic horizon at a depth of 100 cm or more.

Grossarenic Kandiudults

HCCH.  Other Kandiudults that have both of the following:

1.  An ECEC of 1.5 cmol(+)/kg clay or less (sum of bases extracted with 1N NH4OAc pH 7, plus 1N KCl-extractable

Al) in one or more horizons within 150 cm of the mineral soil surface; and

2.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Acrudoxic Plinthic Kandiudults

HCCI.  Other Kandiudults that have an ECEC of 1.5 cmol(+)/kg clay or less (sum of bases extracted with 1N NH4OAc pH 7, plus 1N KCl-extractableAl) in one or more horizons within 150 cm of the mineral soil surface.

Acrudoxic Kandiudults

HCCJ.  Other Kandiudults that have both of the following:

1.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface; and

2.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Plinthaquic Kandiudults

HCCK.  Other Kandiudults that have both of the following:

1.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage); and

2.  Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, one or more of the following:

a.  Afine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0; or

b.  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

c.  Afine-earth fraction containing 30 percent or more particles 0.02 to 2.0 mm in diameter; and

(1)  In the 0.02 to 2.0 mm fraction, 5 percent or more volcanic glass; and

(2)  [(Al plus 1/2 Fe, percent extracted by ammonium oxalate) times 60] plus the volcanic glass (percent) is equal to 30 or more.

Aquandic Kandiudults

HCCL.  Other Kandiudults that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Kandiudults

HCCM.  Other Kandiudults that have, in one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Kandiudults

HCCN.  Other Kandiudults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Kandiudults

HCCO.  Other Kandiudults that:

1.  Have, in one or more horizons within 75 cm of the mineral soil surface, redox concentrations, a color value, moist, of 4 or more, and hue that is 10YR or yellower and becomes redder with increasing depth within 100 cm of the mineral soil surface; and

2.  In normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

with water in one or more layers within 100 cm of the mineral soil surface for either or both:

1.  20 or more consecutive days; or

2.  30 or more cumulative days.

Oxyaquic Kandiudults

HCCQ.  Other Kandiudults that have a sombric horizon within

150 cm of the mineral soil surface.

Sombric Kandiudults

HCCR.  Other Kandiudults that have, in all subhorizons in the upper 75 cm of the kandic horizon or throughout the entire

kandic horizon if it is less than 75 cm thick, more than 50 percent colors that have all of the following:

1.  Hue of 2.5YR or redder; and 2.  A value, moist, of 3 or less; and

3.  A dry value no more than 1 unit higher than the moist value.

Rhodic Kandiudults

HCCS.  Other Kandiudults.

Typic Kandiudults

Kanhapludults

Key to Subgroups

HCDA.  Kanhapludults that have a lithic contact within 50 cm of the mineral soil surface.

Lithic Kanhapludults

HCDB.  Other Kanhapludults that have both of the following:

1.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface; and

2.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Plinthaquic Kanhapludults

HCDC.  Other Kanhapludults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Arenic Plinthic Kanhapludults

HCDD.  Other Kanhapludults that have a texture class (fineearth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm.

Arenic Kanhapludults

HCDE.  Other Kanhapludults that have an ECEC of 1.5 cmol(+)/kg clay or less (sum of bases extracted with 1N NH4OAc pH 7, plus 1N KCl-extractableAl) in one or more horizons within 150 cm of the mineral soil surface.

Acrudoxic Kanhapludults

HCDF.  Other Kanhapludults that have both of the following: 1.  Fragic soil properties either:

a.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

b.  In 60 percent or more of the volume of a layer 15 cm or more thick; and

2.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Fragiaquic Kanhapludults

HCDG.  Other Kanhapludults that have, throughout one or more horizons with a total thickness of 18 cm or more within

75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Kanhapludults

HCDH.  Other Kanhapludults that have, in one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Kanhapludults

HCDI.  Other Kanhapludults that:

1.  Have, in one or more horizons within 75 cm of the mineral soil surface, redox concentrations, a color value, moist, of 4 or more, and hue that is 10YR or yellower and becomes redder with increasing depth within 100 cm of the mineral soil surface; and

2.  In normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

with water in one or more layers within 100 cm of the mineral soil surface for either or both:

1.  20 or more consecutive days; or

2.  30 or more cumulative days.

Oxyaquic Kanhapludults

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HCDK.  Other Kanhapludults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Kanhapludults

HCDL.  Other Kanhapludults that have fragic soil properties either:

1.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

2.  In 60 percent or more of the volume of a layer 15 cm or more thick.

Fragic Kanhapludults

HCDM.  Other Kanhapludults that have, in all subhorizons in the upper 50 cm of the kandic horizon or throughout the entire kandic horizon if it is less than 50 cm thick, more than 50 percent colors that have all of the following:

1.  Hue of 2.5YR or redder; and 2.  A value, moist, of 3 or less; and

3.  A dry value no more than 1 unit higher than the moist value.

Rhodic Kanhapludults

HCDN.  Other Kanhapludults.

Typic Kanhapludults

Paleudults

Key to Subgroups

HCEA.  Paleudults that have one or both of the following:

1.  Cracks within 125 cm of the mineral 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 wedgeshaped peds in a layer 15 cm or more thick that has its upper boundary within 125 cm of the mineral soil surface; or

2.  Alinear extensibility of 6.0 cm or more between the mineral soil surface and either a depth of 100 cm or a densic, lithic, or paralithic contact, whichever is shallower.

Vertic Paleudults

HCEB.  Other Paleudults that have a horizon 5 cm or more thick, either below an Ap horizon or at a depth of 18 cm or more from the mineral soil surface, whichever is deeper, that has one or more of the following:

1.  In 25 percent or more of each pedon, cementation by organic matter and aluminum, with or without iron; or

2.  Al plus 1/2 Fe percentages (by ammonium oxalate)

totaling 0.25 or more, and half that amount or less in an overlying horizon; or

3.  An ODOE value of 0.12 or more, and a value half as high or lower in an overlying horizon.

Spodic Paleudults

HCEC.  Other Paleudults that have all of the following:

1.  Atexture 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 mineral soil surface to the top of an argillic horizon at a depth of 50 cm or more; and

2.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface; and

3.  In one or more layers either within 75 cm of the mineral soil surface or, if the chroma throughout the upper 75 cm results from uncoated sand grains, within the upper 12.5 cm of the argillic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Arenic Plinthaquic Paleudults

HCED.  Other Paleudults 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 mineral soil surface to the top of an argillic horizon that is 50 cm or more below the mineral soil surface; and

2.  Have, in one or more layers either within 75 cm of the mineral soil surface or, if the chroma throughout the upper 75 cm results from uncoated sand grains, within the upper 12.5 cm of the argillic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and

aquic conditions for some time in normal years (or artificial drainage).

1.  5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface; and

2.  In one or more layers either within 75 cm of the mineral soil surface or, if the chroma throughout the upper 75 cm results from uncoated sand grains, within the upper 12.5 cm of the argillic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied

by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Plinthaquic Paleudults

HCEG.  Other Paleudults that have both of the following: 1.  Fragic soil properties either:

a.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

b.  In 60 percent or more of the volume of a layer 15 cm or more thick; and

2.  In one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Fragiaquic Paleudults

HCEH.  Other Paleudults that have, in one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Paleudults

HCEI.  Other Paleudults that in normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

1.  20 or more consecutive days; or

2.  30 or more cumulative days.

Oxyaquic Paleudults

HCEJ.  Other Paleudults that have an argillic horizon that:

1.  Consists entirely of lamellae; or

2.  Is a combination of two or more lamellae and one or more subhorizons with a thickness of 7.5 to 20 cm, each layer with an overlying eluvial horizon; or

3.  Consists of one or more subhorizons that are more than 20 cm thick, each with an overlying eluvial horizon, and above these horizons there are either:

a.  Two or more lamellae with a combined thickness of 5 cm or more (that may or may not be part of the argillic horizon); or

b.  A combination of lamellae (that may or may not be part of the argillic horizon) and one or more parts of the argillic horizon 7.5 to 20 cm thick, each with an overlying eluvial horizon.

Lamellic Paleudults

HCEK.  Other Paleudults 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 mineral soil surface to the top of an argillic horizon at a depth of 50 to 100 cm; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Arenic Plinthic Paleudults

HCEL.  Other Paleudults that have a sandy particle-size class throughout the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick.

Psammentic Paleudults

HCEM.  Other Paleudults 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 mineral soil surface to the top of an argillic horizon at a depth of 100 cm or more; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Grossarenic Plinthic Paleudults

HCEN.  Other Paleudults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Paleudults

HCEO.  Other Paleudults 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 mineral soil surface to the top of an argillic horizon at a depth of 50 to 100 cm; and

2.  Have, in all subhorizons in the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick, more than 50 percent colors that have all of the following:

fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending

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from the mineral soil surface to the top of an argillic horizon at a depth of 50 to 100 cm.

Arenic Paleudults

HCEQ.  Other Paleudults 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 mineral soil surface to the top of an argillic horizon at a depth of 100 cm or more.

Grossarenic Paleudults

HCER.  Other Paleudults that have fragic soil properties either:

1.  In 30 percent or more of the volume of a layer 15 cm or more thick that has its upper boundary within 100 cm of the mineral soil surface; or

2.  In 60 percent or more of the volume of a layer 15 cm or more thick.

Fragic Paleudults

HCES.  Other Paleudults that have, in all subhorizons in the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick, more than 50 percent colors that have all of the following:

1.  Hue of 2.5YR or redder; and 2.  A value, moist, of 3 or less; and

3.  A dry value no more than 1 unit higher than the moist value.

Rhodic Paleudults

HCET.  Other Paleudults.

Typic Paleudults

Plinthudults

Key to Subgroups

HCAA.  All Plinthudults.

Typic Plinthudults

Rhodudults

Key to Subgroups

HCFA.  Rhodudults that have a lithic contact within 50 cm of the mineral soil surface.

Lithic Rhodudults

HCFB.  Other Rhodudults that have a sandy particle-size class throughout the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick.

Psammentic Rhodudults

HCFC.  Other Rhodudults.

Typic Rhodudults

Ustults

Key to Great Groups

HDA.  Ustults that have one or more horizons within 150 cm of the mineral soil surface in which plinthite either forms a continuous phase or constitutes one-half or more of the volume.

Plinthustults, p. 302

HDB.  Other Ustults that:

1.  Do not have a densic, lithic, paralithic, or petroferric contact within 150 cm of the mineral soil surface; and

2.  Have a kandic horizon; and

3.  Within 150 cm of the mineral soil surface, either:

a.  With increasing depth, do not have a clay decrease of 20 percent or more (relative) from the maximum clay content; or

b.  Have 5 percent or more (by volume) skeletans on faces of peds in the layer that has a 20 percent lower clay content and, below that layer, a clay increase of 3 percent or more (absolute) in the fine-earth fraction.

Kandiustults, p. 299

HDC.  Other Ustults that have a kandic horizon.

Kanhaplustults, p. 300

HDD.  Other Ustults that:

1.  Do not have a densic, lithic, paralithic, or petroferric contact within 150 cm of the mineral soil surface; and

2.  Within 150 cm of the mineral soil surface, either:

a.  With increasing depth, do not have a clay decrease of 20 percent or more (relative) from the maximum clay content; or

b.  Have 5 percent or more (by volume) skeletans on faces of peds in the layer that has a 20 percent lower clay content and, below that layer, a clay increase of 3 percent or more (absolute) in the fine-earth fraction.

Paleustults, p. 301

HDE.  Other Ustults that have both of the following:

1.  An epipedon that has a color value, moist, of 3 or less throughout; and

2.  In all subhorizons in the upper 100 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 100 cm thick, more than 50 percent colors that have all of the following:

value.

Rhodustults, p. 302

HDF.  Other Ustults.

Haplustults, p. 299

Haplustults

Key to Subgroups

both within the upper 12.5 cm of the argillic horizon and within

75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Haplustults

HDFD.  Other Haplustults that have a texture class (fineearth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the mineral soil surface to the top of an argillic horizon at a depth of 50 cm or more below the mineral soil surface.

Arenic Haplustults

HDFE.  Other Haplustults that:

1.  Have, in one or more horizons within 75 cm of the mineral soil surface, redox concentrations, a color value, moist, of 4 or more, and hue that is 10YR or yellower and becomes redder with increasing depth within 100 cm of the mineral soil surface; and

2.  In normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Haplustults

HDFG.  Other Haplustults that have a CEC (by 1N NH4OAc pH 7) of less than 24 cmol(+)/kg clay in 50 percent or more of the entire argillic horizon if less than 100 cm thick or of its upper 100 cm.

Kanhaplic Haplustults

HDFH.  Other Haplustults.

Typic Haplustults

Kandiustults

Key to Subgroups

HDBA.  Kandiustults that have an ECEC of 1.5 cmol(+)/kg clay or less (sum of bases extracted with 1N NH4OAc pH 7, plus 1N KCl-extractableAl) in one or more horizons within 150 cm of the mineral soil surface.

Acrustoxic Kandiustults

HDBB.  Other Kandiustults that have, in one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Kandiustults

HDBC.  Other Kandiustults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 cm or more; and

2.  Have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Arenic Plinthic Kandiustults

1.  Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0; and

U L T

2.  When neither irrigated nor fallowed to store moisture, either:

a.  A mesic or thermic soil temperature regime and a moisture control section that is dry in some part for 135 or fewer of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

b.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that is dry in some or all parts for fewer than 120 cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 8 oC.

Udandic Kandiustults

HDBF.  Other Kandiustults that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Kandiustults

HDBG.  Other Kandiustults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Kandiustults

HDBH.  Other Kandiustults that, when neither irrigated nor fallowed to store moisture, have either:

1.  A thermic, mesic, or colder soil temperature regime and a moisture control section that in normal years is dry in some part for more than four-tenths of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

2.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that in normal years:

fallowed to store moisture, have either:

1.  A mesic or thermic soil temperature regime and a moisture control section that in normal years is dry in some

part for 135 or fewer of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

2.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that in normal years is dry in some or all parts for fewer than 120 cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 8 oC.

Udic Kandiustults

HDBJ.  Other Kandiustults that have, in all subhorizons in the upper 75 cm of the kandic horizon or throughout the entire kandic horizon if it is less than 75 cm thick, more than 50 percent colors that have all of the following:

1.  Hue of 2.5YR or redder; and 2.  A value, moist, of 3 or less; and

3.  A dry value no more than 1 unit higher than the moist value.

Rhodic Kandiustults

HDBK.  Other Kandiustults.

Typic Kandiustults

Kanhaplustults

Key to Subgroups

HDCA.  Kanhaplustults that have a lithic contact within 50 cm of the mineral soil surface.

Lithic Kanhaplustults

HDCB.  Other Kanhaplustults that have an ECEC of 1.5 cmol(+)/kg clay or less (sum of bases extracted with 1N NH4OAc pH 7, plus 1N KCl-extractableAl) in one or more horizons within 150 cm of the mineral soil surface.

Acrustoxic Kanhaplustults

HDCC.  Other Kanhaplustults that have, in one or more layers within 75 cm of the mineral soil surface, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Kanhaplustults

HDCD.  Other Kanhaplustults 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 mineral soil surface to the top of a kandic horizon at a depth of 50 to 100 cm.

Arenic Kanhaplustults

HDCE.  Other Kanhaplustults that have both of the following: