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FSM 2500 – WATERSHED AND AIR MANAGEMENT
CHAPTER 2550
– SOIL MANAGEMENT
Supplement No.: R-10 2500-2006-1
Effective Date: May 5, 2006
Duration: This supplement is effective until superseded or removed.
Approved:
/s/ Paul K. Brewster (for) Date Approved: 04/17/2006
DENNIS E. BSCHOR
Regional Forester
Posting Instructions: Supplements are numbered consecutively by title number and calendar year. Post by document; remove the entire document and replace it with this supplement. Retain this transmittal as the first page(s) of this document. The last supplement to this title was R-10
2500-2005-3 to chapter 2580.
5 Pages New Document
Superseded Document(s) by
Issuance Number and
Effective Date
2550
2551.12a-2551.3 (R-10 Supp 13, 1/83)
2554 (2500-92-1, 1/15/92)
2555 (R-10 Supp 3, 1/68)
2557.2 (R-10 Supp 13, 1/68)
Digest:
2554:
Defines acceptable levels of change in soils properties.
Removes soil quality monitoring standards
4 Pages
6 Pages
1 Page
1 Page

R-10 SUPPLEMENT 2500-2006-1
EFFECTIVE DATE: 05/05/2006
DURATION: This supplement is effective until superseded or removed.
FSM 2500 – WATERSHED AND AIR MANAGEMENT
CHAPTER 2550 – SOIL MANAGEMENT
2550
Page 2 of 5
2554 - SOIL QUALITY MONITORING
This supplement establishes soil quality monitoring standards for soil disturbance created by any management activity. Any greater soil disturbance, exceeding the standards, constitutes significant impairment to the productivity of the land. These standards are necessary for directing and conducting soil quality monitoring and evaluation programs on National Forest
System lands in the Alaska Region.
These definitions are supplemental to those in FSH 2509.18, Soil Management Handbook.
1. Activity Area. The total area of ground surface impacted by an activity (timber sale unit, road segment or plant association). It must be a feasible unit for sampling and evaluation and excludes specified transportation facilities and dedicated trails.
2. Altered Wetness. The interruption of subsurface drainage by making the soils wetter or dryer impacts long-term site productivity. This is generally associated with the construction of roads and trails across a muskeg or other types of wetlands. Detrimental altered wetness is identified when an area becomes perennially flooded or drained and the effective function or value of the wetland is lost.
3. Bulk Density. Soil bulk density is the mass (oven dry weight) of fine earth (particles
< 2 mm) per volume of moist (10kPa) fine earth.
4. Burned. The burning of forest litter and duff layers may be beneficial in some sites.
Soils are considered detrimentally burned when most woody debris and the entire forest floor is consumed down to bare mineral soil or rock. Soil may have turned red due to extreme heat and the fine roots and organic matter are charred in the upper one-half inch of mineral soil. This can also be referred to as severely burned or high fire intensity.
5. Compaction. Compaction of soil decreases porosity and increases soil strength and bulk density as a result of the application of mechanical forces such as weight and vibration.
Compaction increases with repeated application of compactive forces. It is considered detrimental if bulk density is increased more than 15 percent over the undisturbed levels.
6. Displacement. Soil displacement is the horizontal movement of soil from one place to another by mechanical forces such as a blade, wheel slippage, or dragging logs. Detrimental displacement is the removal of the forest floor and 50 percent of the top soil or humus-enriched surface soil, from an area of 100 square feet or more which is at least 5 foot in width. Mixing of surface soils and organic humus by machinery or removal of small areas by scalping for planting purposes is not considered detrimental.

R-10 SUPPLEMENT 2500-2006-1
EFFECTIVE DATE: 05/05/2006
DURATION: This supplement is effective until superseded or removed.
FSM 2500 – WATERSHED AND AIR MANAGEMENT
CHAPTER 2550 – SOIL MANAGEMENT
2550
Page 3 of 5
7. Erosion. Erosion is the detachment and transport of individual soil particles, or aggregates of particles, by ice, wind, water, or gravity. Management practices that increase the erosion rates or mass wasting frequency above natural levels are considered accelerated and detrimental.
Surface erosion occurs as the loss of soil by gravity (dry ravel) or by water as both raindrop splash and overland flow. The rate of erosion generally increases as slope percent increases and ground cover decreases. It is considered detrimental when 50 percent of the topsoil, or humusenriched surface soil from an area of 100 square feet or more is removed.
Mass wasting occurs when large masses of soil and/or rock fall, slide, or flow down a slope. All mass wasting created by management activity is considered detrimental to long-term site productivity.
8. Ground Cover. Ground cover, such as rock fragments larger than 1/2 inch, low growing vegetation (grasses, forbs, and prostrate shrubs), plant litter and debris is more effective than shrub or tree cover for resisting the effects of raindrop impact and surface erosion. Ground cover is based on the amount of surface area it covers. Soil cover is considered to be uniform if more than half of an area is consistently within the percentage range. The cover is considered patchy when more than half of an area falls outside the percentage range.
9. Puddling. Soil puddling is a physical change in soil properties due to shearing forces that alter soil structure and reduce porosity. Detrimental puddling is defined as identifiable ruts or foot prints in mineral soil or in an Oa horizon of an organic soil, caused by heavy equipment operation or recreational traffic.
10. Significant Changes. Significant change in productivity of the soil (the soil component of site productivity) is indicated by changes in soil properties that are expected to result in a reduced productive capacity over the planning horizon. Based on available research and current technology, a guideline of 15-percent reduction in inherent soil productivity potential will be used as a basis for setting values for change in measurable or observable soil properties.
11. Significant Impairment. Significant impairment of the productivity of the land includes changes in soil properties which would result in significant changes in the inherent productivity that lasts beyond the planning horizon.
12. Soil Conservation Practices. Soil conservation practices are the mechanisms used to protect soil quality while meeting other resource goals and objectives. They can be administrative, preventive or corrective in nature and are generally identified during project planning and design. The Soil and Water Conservation Handbook (FSH 2509.22, Region 10
Amendment No. 2), commonly called Best Management Practices, contains specific conservation practices for use in the Alaska Region. Other practices which protect soil productivity may also be applied.

R-10 SUPPLEMENT 2500-2006-1
EFFECTIVE DATE: 05/05/2006
DURATION: This supplement is effective until superseded or removed.
FSM 2500 – WATERSHED AND AIR MANAGEMENT
CHAPTER 2550 – SOIL MANAGEMENT
2550
Page 4 of 5
13. Soil Productivity. Soil productivity (the soil component of long-term site productivity) is the inherent capacity of a soil to support the growth of specified plants, plant communities, or a sequence of plant communities. Soil productivity may be expressed in terms of volume or weight/unit area/year, percent plant cover, or other measures of biomass accumulation.
2554.02 – Objective
To meet the direction in the National Forest Management Act of 1976 and other legal mandates.
To manage National Forest System lands under principals of multiple use and sustained yield without permanent impairment of land productivity, and maintain or improve soil productivity.
Specific objectives are:
1. Plan and conduct land management activities so reductions of soil productivity potential caused by detrimental compaction, displacement, puddling, alter wetness, and severe burning are minimized. Maintain nutrient capital on all lands at acceptable levels.
2. Plan and conduct land management activities so soil loss from accelerated surface erosion and mass wasting, caused by those activities, will not result in an unacceptable reduction in soil productivity and water quality.
3. The Alaska Region, and Forests within it, will have realistic, measurable soil protection standards and guidelines that can be monitored and are in accordance with, and supportive of, land management objectives as outlined in Land Management Plan or other resource plans.
2554.03 – Policy
Environmental Assessments and Environmental Impact Statements will address the potential of affecting soils from compaction, puddling, displacement, surface erosion, altered wetness, and damage by severe burning if these are identified as concerns during the Interdisciplinary Team process or other appropriate stages of project development. When detrimental impacts are likely to be caused by an activity, develop and evaluate alternative prescriptions. To achieve established soil management objectives, plan appropriate mitigating and/or rehabilitation measures.
Plan and conduct monitoring activities to determine if soil productivity protection objectives and standards are met and realistic.
Schedule periodic management reviews to determine if soil management objectives are achieved.

R-10 SUPPLEMENT 2500-2006-1
EFFECTIVE DATE: 05/05/2006
DURATION: This supplement is effective until superseded or removed.
FSM 2500 – WATERSHED AND AIR MANAGEMENT
CHAPTER 2550 – SOIL MANAGEMENT
2550
Page 5 of 5
Soil quality standards are the allowable levels of change and will provide reasonable assurance that no long-term losses in inherent productivity of the soil will result. They represent the maximum tolerable disturbance levels, and are combinations of: (1) values for severity of soil property alteration and (2) a real extent of disturbance.
1. Values for Severity. As defined below.
2. Areal Extent Standards for the Alaska Region. a. Detrimental Compaction, Displacement, Puddling, Mass Movement, Erosion, and
Severely Burned. Leave a minimum of 85 percent of an area in a condition of acceptable productivity potential for trees and other managed vegetation following land management activities. Specified (system) roads which include cut, fill, road bed, landings and log transfer facilities are excluded from the activity area, but side cast and other waste materials are not excluded. b. Ground Cover. The minimum percent effective and uniform ground cover, following a ground disturbing activity, must be at least:
85 percent ground cover on slopes less then 35 percent,
90 percent ground cover on 35-75 percent slopes or,
95 percent ground cover on slopes over 75 percent. c. Soil Drainage and Wetness. Detrimental altered wetness can occur in no more than
5 percent of an activity area.
3. Assessment. The total acreage of all detrimental soil conditions should not exceed 15 percent of the total acreage within the activity area minus exclusions. Consider restoration treatments if detrimental conditions are about 15 percent or more of the activity area.