R2 SUPPLEMENT 2509.18-92-12509.18_2
EFFECTIVE 8/15/92Page 1 of 1
FOREST SERVICE HANDBOOK
DENVER, CO
FSH 2509.18 - SOIL MANAGEMENT HANDBOOK
R2 Supplement No. 2509.18-92-1
Effective August 15, 1992
POSTING NOTICE. Supplements to this title are numbered consecutively. Post by document name. This is the first Region 2 Supplement to this handbook. Retain this transmittal as the first page of this document.
Superseded New
Document Name(Number of Pages)
2509.18_23
Digest:
Establishes Regional Soil Quality Monitoring Standards.
TOM L. THOMPSON
Acting Regional Forester
FSH 2509.18 - SOIL MANAGEMENT HANDBOOK
CHAPTER 2 - SOIL QUALITY MONITORING
2.03 - POLICY.
1. Management activities will be conducted in such a way as to not exceed the Soil Quality Standards. The emphasis is on protecting the soil resource before excessive damage occurs.
2. Where excessive soil impacts already exist from prior activity, the emphasis shall be on preventing any additional detrimental impact, and on reclamation where feasible.
2.05 - DEFINITIONS.
10. Detrimental Compaction:
a. A 15% increase in bulk density from the average undisturbed density, or
b. Bulk density values that exceed the following Threshold Values:
1.25 g/cc - Silt and Clay,
1.30 g/cc - Silty Clay, Silty Clay Loam and Silt Loam,
1.40 g/cc - Loam and Clay Loam,
1.50 g/cc - Sandy Loam, Sandy Clay Loam and Sandy Clay,
1.60 g/cc - Sand and Loamy Sand.
11. Detrimental Displacement - The removal of soil from a continuous area of 100 square feet or more.
12. Detrimental Erosion.
a. Sheet Erosion - The general loss of soil from the soil surface. Indicators include pedestalled rocks and plants, deposition of soil on the uphill side of rocks and plants, and/or erosion pavement.
b. Rills and Gullies - Erosion channels greater than one-inch deep.
13. Effective Ground cover - All living and dead herbaceous and woody materials in contact with the ground and all rocks greater than 3/4 inch in diameter.
14. Detrimental Puddling - Detrimental Puddling typically occurs in conjunction with detrimental compaction. Detrimental Compaction will be used to monitor Detrimental Puddling.
15. Activity Area - An area of land impacted by a management activity or activities. It can range from a few acres to an entire watershed depending on the type of monitoring being conducted. It is commonly a timber sale cutting unit.
2.2 - SOIL QUALITY STANDARDS.
3. Detrimental Compaction, Displacement, Puddling, Severe Burning and Erosion. No more than 15 percent of an activity area will be left in a detrimentally compacted, displaced, puddled, severely burned, and/or eroded condition. This does not include the permanent transportation system.
4. Effective Ground Cover. Required Minimum Percent Effective Groundcover for the first and second year after disturbance:
Erosion Hazard Class / 1st Year / 2nd Year(%) / (%)
Low / 50 / 70
Moderate / 40 / 60
High / 30 / 50
Very High / 30 / 50
Project plans which propose to exceed Regional standards for Detrimental Compaction, Displacement, Puddling, Severe Burning, and Erosion should contain justification and planned mitigation, and be approved by the Forest Supervisor.
Standards for Detrimental Compaction, Displacement, Severe Burning, and Erosion apply to the cumulative effects of management practices over time. If a standard is exceeded in an initial entry, future entries must have no additional detrimental effect unless mitigative measures have been applied or natural recovery has taken place between entries.
2.42 - SOIL SAMPLING TECHNIQUES. Sampling techniques range from extensive visual observations to intensive sampling techniques using statistically sound methodologies. The intensity of sampling must be determined on a case by case basis depending on the values and risks at stake.
"Guidelines For Sampling Some Physical Conditions of Surface Soils" by Howes, Hazard, and Geist (1983), has proven to be an effective intensive sampling technique. When the local site variability is unknown, approximately 20, 100 foot transects should be used.
Soil core samplers, nuclear gages, and cone penetrometers have all been used successfully to measure soil bulk densities. Other methods may be used provided they have been properly validated in the field.