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BBC.Haplofibrists

Key to Great Groups 

BBC. Other Fibrists. Haplofibrists, p. 476 

BBC. These are the Fibrists in which the temperature regime is warmer than cryic and less than three-fourths of the fiber volume is derived from Sphagnum. The fibers may have been derived from wood, grasses, sedges, mosses, and other herbaceous plants or from some combination of these. If these soils are drained and cultivated under the present technology, the organic materials will decompose either slowly or rapidly, depending on the management used and the temperature. Eventually, within some decades, the Haplofibrists that are drained and cultivated will be replaced first by Hemists and Saprists and then by mineral soils. Most of these soils in the United States support native vegetation. 

Definition 

Haplofibrists are the Fibrists that:

1. Have a soil temperature regime warmer than cryic;

2. Have less than three-fourths of their fiber volume derived from Sphagnum either in the upper 90 cm or more of the control section or in the soil above a densic, lithic, or paralithic contact, fragmental materials, or mineral soil materials shallower than 90 cm. 

Key to Subgroups 

BBCA. Haplofibrists that have a layer of water within the control section, below the surface tier. Hydric Haplofibrists 

BBCB. Other Haplofibrists that have a lithic contact within the control section. Lithic Haplofibrists 

BBCC. Other Haplofibrists that have one or more limnic layers with a total thickness of 5 cm or more within the control section. Limnic Haplofibrists 

BBCD. Other Haplofibrists that have a mineral layer 30 cm or more thick that has its upper boundary within the control section, below the surface tier. Terric Haplofibrists 

BBCE. Other Haplofibrists that have, within the organic materials, either one mineral layer 5 cm or more thick or two or more mineral layers of any thickness in the control section, below the surface tier. Fluvaquentic Haplofibrists 

BBCF. Other Haplofibrists that have one or more layers of hemic and sapric materials with a total thickness of 25 cm or more in the control section, below the surface tier. Hemic Haplofibrists 

BBCG. Other Haplofibrists. Typic Haplofibrists 

Definition of Typic Haplofibrists 

Typic Haplofibrists are the Haplofibrists that:

1. Have a total of less than 25 cm hemic and sapric materials below the surface tier;

2. Do not have a limnic layer(s) 5 cm or more thick within the control section;

3. Do not have a lithic contact within the control section;

4. Do not have a mineral layer between 5 and 30 cm thick or two or more thin, continuous mineral layers within the organic materials in the control section, below the surface tier;

5. Do not have a mineral layer 30 cm or more thick that has its upper boundary within the control section, below the surface tier; and

6. Do not have a layer of water within the control section, below the surface tier.

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