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The Hard Labor series consists of very deep, moderately well drained, slowly permeable soils that formed in material weathered from felsic igneous and metamorphic rock, primarily granite and granite gneiss. The Hard Labor soils are on summits and side slopes of the Piedmont uplands.

Typically, the Bt horizon is yellowish brown (10YR 5/6) clay with moderate coarse subangular blocky structure parting to moderate thick platy structure. It is firm, slightly sticky and moderately plastic and has common fine and very fine roots; common prominent light yellowish brown (2.5Y 6/3) clay films on faces of peds, in pores, and in former root channels; few fine flakes of mica; few fine red (2.5YR 4/8) masses of oxidized iron on faces of peds and is moderately acid.

This layer acts as an aquitard, perching water in late winter and early spring.

Slake tests are performed to identify the possible presence of coherent/cemented materials. Only air-dry soil fragments or aggregates should be tested by the slaking procedure. Large intact samples are separated into fist size aggregates <75-mm in size. Care should be taken not to destroy naturally cemented aggregates (e.g., potential plinthite nodules) as the material is separated. Submersion is for a minimum of one hour, but overnight (about 8 hours) is preferred.

For a complete discussion, visit:
Soil Survey Field and Laboratory Methods Manual
Soil Survey Investigations Report No. 51, Version 2
Issued 2014

3.7 Soil Stability, Dispersion, and Slaking (pp.148-162)
3.7.5 Slaking (Disaggregation) for Identification and Semiquantification of Cemented Materials
John Kelley and Michael A. Wilson, United States Department of Agriculture, Natural Resources Conservation Service, Soil Survey Staff

Citation: Soil Survey Staff. 2014. Soil Survey Field and Laboratory Methods Manual. Soil Survey Investigations Report No. 51, Version 2.0. R. Burt and Soil Survey Staff (ed.). U.S. Department of Agriculture, Natural Resources Conservation Service.

Slaking v. Disaggregation

As footnoted in the Field Book for Describing and Sampling Soils (FBDSS), disaggregation is or equals “slaking”. However, at one time a distinction was made between materials that disaggregated as opposed to those that slaked. The term "slakes" was limited to fragments that exhibited a violent rupture as the fragments break down (a popping off of the materials as opposed to simply sloughing away). This is a common characteristic of fragments taken from a fragipan and is used by many to identify fragic soil properties.

Currently, slaking is defined as the breakdown of soil aggregates into smaller microaggregates when the aggregates are immersed in water. The slake test provides a measure of soil stability when soil aggregates are exposed to rapid wetting. No distinction is now made as to how the material reacts as it disaggregates.

Only air-dry soil fragments or aggregates should be tested by the slaking procedure. Large intact samples are separated into fist size aggregates <75-mm in size. Care should be taken not to destroy naturally cemented aggregates (e.g., potential plinthite nodules) as the material is separated. Submersion is for a minimum of one hour, but overnight (about 8 hours) is preferred.

For a complete discussion, visit:
Soil Survey Field and Laboratory Methods Manual
Soil Survey Investigations Report No. 51, Version 2
Issued 2014

3.7 Soil Stability, Dispersion, and Slaking (pp.148-162)
3.7.5 Slaking (Disaggregation) for Identification and Semiquantification of Cemented Materials
John Kelley and Michael A. Wilson, United States Department of Agriculture, Natural Resources Conservation Service, Soil Survey Staff

Citation: Soil Survey Staff. 2014. Soil Survey Field and Laboratory Methods Manual. Soil Survey Investigations Report No. 51, Version 2.0. R. Burt and Soil Survey Staff (ed.). U.S. Department of Agriculture, Natural Resources Conservation Service.

Slaking v. Disaggregation

As footnoted in the Field Book for Describing and Sampling Soils (FBDSS), disaggregation is or equals “slaking”. However, at one time a distinction was made between materials that disaggregated as opposed to those that slaked. The term "slakes" was limited to fragments that exhibited a violent rupture as the fragments break down (a popping off of the materials as opposed to simply sloughing away). This is a common characteristic of fragments taken from a fragipan and is used by many to identify fragic soil properties.

Currently, slaking is defined as the breakdown of soil aggregates into smaller microaggregates when the aggregates are immersed in water. The slake test provides a measure of soil stability when soil aggregates are exposed to rapid wetting. No distinction is now made as to how the material reacts as it disaggregates.

Only air-dry soil fragments or aggregates should be tested by the slaking procedure. Large intact samples are separated into fist size aggregates <75-mm in size. Care should be taken not to destroy naturally cemented aggregates (e.g., potential plinthite nodules) as the material is separated. Submersion is for a minimum of one hour, but overnight (about 8 hours) is preferred.

For a complete discussion, visit:
Soil Survey Field and Laboratory Methods Manual
Soil Survey Investigations Report No. 51, Version 2
Issued 2014

3.7 Soil Stability, Dispersion, and Slaking (pp.148-162)
3.7.5 Slaking (Disaggregation) for Identification and Semiquantification of Cemented Materials
John Kelley and Michael A. Wilson, United States Department of Agriculture, Natural Resources Conservation Service, Soil Survey Staff

Citation: Soil Survey Staff. 2014. Soil Survey Field and Laboratory Methods Manual. Soil Survey Investigations Report No. 51, Version 2.0. R. Burt and Soil Survey Staff (ed.). U.S. Department of Agriculture, Natural Resources Conservation Service.