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FAG.Endoaquerts

Key to Great Groups 

FAG. Other Aquerts. Endoaquerts, p. 791 

FAG. Endoaquerts are the Aquerts that do not have a soil layer that perches water. These soils commonly are wet from the bottom to the top. They occur in the Far Western States, on the northern Great Plains, and in the Southern States. Before 1992, most were considered Haplaquepts.

Definition 

Endoaquerts are the Aquerts that:

1. Do not have a salic or calcic horizon or a duripan that has its upper boundary within 100 cm of the mineral soil surface;

2. Do not have both of the following:

                a. An electrical conductivity in the saturation extract of less than 4.0 dS/m at 25 oC; and

                b. A pH value of 4.5 or less in 0.01 M CaCl2 (5.0 or less in 1:1 water) in more than 50 percent of the soil volume between the mineral soil surface and a depth of 50 cm in each pedon;

3. Have endosaturation; and

4. Do not have a natric horizon or an exchangeable sodium percentage of 15 percent or more (or a sodium adsorption ratio of 13 or more) within 100 cm of the mineral soil surface. 

Key to Subgroups 

FAGA. Endoaquerts that have, throughout a layer 15 cm or more thick within 100 cm of the mineral soil surface, an electrical conductivity of 15 dS/m or more (saturated paste) for 6 or more months in normal years. Halic Endoaquerts 

FAGB. Other Endoaquerts that have, in one or more horizons within 100 cm of the mineral soil surface, an exchangeable sodium percentage of 15 or more (or a sodium adsorption ratio of 13 or more) for 6 or more months in normal years. Sodic Endoaquerts 

FAGC. Other Endoaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 210 or more cumulative days per year. Aridic Endoaquerts 

FAGD. Other Endoaquerts that have a thermic, mesic, or frigid soil temperature regime and that, if not irrigated during the year, have cracks in normal years that remain both:

1. 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more consecutive days during the 90 days following the summer solstice; and

2. Closed for 60 or more consecutive days during the 90 days following the winter solstice. Xeric Endoaquerts 

FAGE. Other Endoaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year. Ustic Endoaquerts 

FAGF. Other Endoaquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and a depth of 75 cm, 50 percent or more colors as follows:

1. Hue of 2.5Y or redder and either:

                a. A color value, moist, of 6 or more and chroma of 3 or more; or

                b. A color value, moist, of 5 or less and chroma of 2 or more; or

2. Hue of 5Y and chroma of 3 or more; or

3. Chroma of 2 or more and no redox concentrations. Aeric Endoaquerts 

FAGG. Other Endoaquerts that have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface. Leptic Endoaquerts 

FAGH. Other Endoaquerts that have a layer 25 cm or more thick that contains less than 27 percent clay in its fine-earth fraction and has its upper boundary within 100 cm of the mineral soil surface. Entic Endoaquerts 

FAGI. Other Endoaquerts that have, in one or more horizons within 30 cm of the mineral soil surface, one or both of the following in more than half of each pedon:

1. A color value, moist, of 4 or more; or

2. A color value, dry, of 6 or more. Chromic Endoaquerts 

FAGJ. Other Endoaquerts. Typic Endoaquerts 

Definition of Typic Endoaquerts 

Typic Endoaquerts are the Endoaquerts that:

1. Do not have both a thermic, mesic, or frigid soil temperature regime and, if not irrigated during the year, cracks in normal years that remain both:

                a. 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more consecutive days during the 90 days following the summer solstice; and

                b. Closed for 60 or more consecutive days during the 90 days following the winter solstice;

2. If not irrigated during the year, do not have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year;

3. Do not have, in any horizon between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and a depth of 75 cm, any of the following in more than half of each pedon:

                a. Hue of 2.5Y or redder and either:

                                (1) A color value, moist, of 6 or more and chroma of 3 or more; or

                                (2) A color value, moist, of 5 or less and chroma of 2 or more; or

                b. Hue of 5Y or yellower and chroma of 3 or more; or

                c. Chroma of 2 or more and no redox concentrations;

4. Do not have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface;

5. Do not have a layer 25 cm or more thick that contains less than 27 percent clay in its fine-earth fraction and has its upper boundary within 100 cm of the mineral soil surface;

6. Have, throughout all layers 15 cm or more thick within 100 cm of the mineral soil surface, an electrical conductivity of less than 15 dS/m (saturated paste) for 6 or more months in normal years;

7. Have, in all horizons within 100 cm of the mineral soil surface, an exchangeable sodium percentage of less than 15 (or a sodium adsorption ratio of less than 13) for 6 or more months in normal years; and

8. Have, in all horizons within 30 cm of the mineral soil surface, one or both of the following in more than half of each pedon:

                a. A color value, moist, of 3 or less; or

                b. A color value, dry, of 5 or less.

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