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Sparta Vegetation Management Project

Soils Existing Conditions and Project Effects

October 15, 2016

Prepared by:

Aric Johnson

Range Management Specialist

Natural Resources RDMA

La Grande Ranger District

Wallowa-Whitman National Forest

Sparta Project Soils Report

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Contents Regulatory Framework ........................................................................................................................... 3

Affected Environment ............................................................................................................................. 4

Project Area Soil Characteristics ......................................................................................................... 4

Project Area LTA Descriptions ........................................................................................................... 8

Soil Impact Surveys and Erosion Risk ................................................................................................ 9

Mass Wasting in Project Area ........................................................................................................... 11

Sparta Soil Productivity .................................................................................................................... 11

Soil Compaction and Displacement .................................................................................................. 12

Past and On-going Vegetation Management Projects ....................................................................... 13

Detrimental Soil Conditions (DSCs) ................................................................................................. 14

Effects ....................................................................................................................................................... 15

Methodology and Assumptions ......................................................................................................... 16

No Direct, Indirect, or Cumulative Effects ........................................................................................... 21

Direct and Indirect Effects .................................................................................................................... 21

Cumulative Effects for Soils ................................................................................................................. 33

Consistency with Laws and Policy .................................................................................................... 35

Monitoring ........................................................................................................................................ 35

References ................................................................................................................................................ 36

Appendix A ........................................................................................................................................... 39

Interim Protocol for Assessment and Management of Soil Quality Conditions ................................ 39


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Introduction

The intent of this report is to provide information on existing soil conditions and expected soil conditions

after project implementation in the Sparta project area. The Sparta Vegetation Management Project area

boundary lies within the Eagle/Paddy and Little Eagle 6th Field Hydrologic Unit Code (HUC)

boundaries, on the Whitman District, Wallowa-Whitman National Forest, in Northeast Oregon. Direct,

indirect, and cumulative effects will be evaluated for the soils resources. Cumulative effects to soils from

on-going activities outside the scope of this project such as firewood gathering or livestock grazing in the

project area may occur within project units, and impacts of these on-going activities on project area soils

are considered along with project impacts where they occur together. The focus for this analysis is the

condition of soils within project units.

Regulatory Framework

The regulatory framework providing direction for protecting soil quality comes from the following

principle sources. These policies and legislation are evolutionary, and have led to the soil management

strategies that are employed on the Wallowa-Whitman National Forest today.

Organic Administration Act of 1897

Bankhead-Jones Act of 1937

Multiple Use-Sustained Yield Act of 1960

National Forest Management Act of 1976 (NFMA)

Forest Service Manual 2500 – Chapter 2550 – Soil Management

Region 6 USDA Forest Service 2520 – watershed protection and management R-6 Supplement

No. 2500.98-1

Wallowa-Whitman National Forest Plan (Forest Plan) and Regional Soil Quality standards (R6

SUPPLEMENT 2500-98-1)

The Organic Administration Act of 1897 (16 U.S.C. 473-475) authorizes the Secretary of Agriculture to

establish regulations to govern the occupancy and use of National Forests and “…to improve and protect

the forest within the boundaries, or for the purpose of securing favorable conditions of water flows, and to

furnish a continuous supply of timber for the use and necessities of citizens of the United States.”

The Bankhead-Jones Act of 1937 authorizes and directs a program of land conservation and land

utilization, in order thereby to correct maladjustments in land use, and thus assist in controlling soil

erosion, preserving natural resources, mitigating floods, conserving surface and subsurface moisture,

protecting the watersheds of navigable streams, and protecting the public lands, health, safety, and

welfare.

The Multiple Use-Sustained Yield Act of 1960 directs the Forest Service to achieve and maintain outputs

of various renewable resources in perpetuity without permanent impairment of the land's productivity.

The National Forest Management Act of 1976 (NFMA) charges the Secretary of Agriculture with

ensuring research and continuous monitoring of each management system to safeguard the land's

productivity. To comply with NFMA, the Chief of the Forest Service has charged each Forest Service

Region with developing soil quality standards for detecting soil disturbance and indicating a loss in long-

term productive potential. These standards are built into Forest Plans.

The FSM 2500 Chapter 2550 Soil Management (1990) directive establishes the framework for sustaining

soil quality and hydrologic function while providing goods and services outlined in forest and grassland


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land management plans. Region 6 USDA Forest Service 2520 – watershed protection and management

R-6 Supplement No. 2500.98-1 also defines soil quality standards.

The Forest Plan objective for soil is to manage the soil resource to maintain long-term productivity. The

objective is that management activities on forest lands will not significantly impair the long-term

productivity of the soil or produce unacceptable levels of sedimentation resulting from soil erosion. The

Forest Plan goal and standards for soils are listed below.

Soils: Goal – Manage Wallowa-Whitman NF lands to maintain or enhance soil and land productivity (p.

4-21).

Pertinent standards for this project include:

Conflicts with other uses. Give maintenance of soil productivity and stability priority over uses

described or implied in all other management direction, standards or guidelines.

Protection. Minimize detrimental disturbance to no more than 20% of an activity area.

Protection. Re-establish vegetation following wild fire or management activities where necessary

to prevent excessive erosion.

The Wallowa-Whitman Forest Plan policy is to ensure that Soil disturbing management practices will

strive to maintain at least 80 percent of an activity area in a condition of acceptable productivity potential

for trees and other managed vegetation. Unacceptable productivity potential exists when soil has been

detrimentally compacted, displaced, puddled, or severely burned as determined in the project analysis.

The regional soil quality standard manual direction (R-6 Supplement 2500-98-1 1998) requires

maintaining 80% of an activity area’s soil at an acceptable productivity potential with respect to

detrimental impacts (USFS, 1984), including the effects of compaction, displacement, rutting, severe

burning, surface erosion, loss of surface organic matter, and soil mass movement. The regional soil

quality standards also state that the maintenance of sufficient organic matter and ground cover, both fine

and coarse woody material is essential for soil productivity.

Affected Environment

Project Area Soil Characteristics

In the Sparta project area, soils within the treatment units occur on 14 soil Landtype Associations (LTAs,

Table 1, Figure 1). LTAs were mapped during a Terrestrial Ecological Unit Inventory (TEUI) assessment

conducted on the Wallowa-Whitman National Forest (WWNF 2002). The LTAs are a product of the

interaction between soils, geology, landforms, vegetation and climate. For this project, soils and their

properties are described by LTAs. They are useful for describing soil characteristics and for helping to

guide management of soils during project implementation. The TEUI was completed through resource

surveys by resource specialists through the integration of an ecosystem's elements, such as soils, geology,

geomorphology, climate and potential natural vegetation. Resource Surveys were completed as part of

the TEUI, and soil properties, suitability for forest management, landslide and erosion risk, and other

management considerations were determined. Soils have been classified as Land Type Associations

(LTAs) based on ecological processes identified in TEUI surveys, and each LTA may consist of several

soil series. Other resource surveys for evaluation of soil conditions in the project area were completed by

the project soil scientist during field seasons in 2008-2010 with updates in 2016.

In much of the area residual soils were buried under, mixed, or have formed within a layer of volcanic ash

deposited from the eruption of Mount Mazama approximately 6000 years ago. Soils with a high amount

of ash in surface horizons are common in the project area, ranging from relatively thick to non-existent.

Ash-cap soils derived from volcanic eruptions are most often classified in the silt or sandy loam

categories. They are also characterized by low bulk density, high porosity, and high water holding


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capacity. They tend to be non-cohesive and because of their relatively low strength, are highly

susceptible to compaction (Johnson, Page-Dumroese and Han 2007). Ash-cap soils can be susceptible to

disturbance during forest management, and strategies to predict compaction, displacement and erosion

hazards are essential for planning forest management operations (Curran, Green, and Maynard 2007).

Table 1. Soil Land Type Association (LTA) Classification and Properties

LTA Soil Series

Name

Soil Extent

(%) Ash Mantle

Surface

Texture

Depth to

Bedrock (ft) Parent Material Soil Climate

116

Limberjim 30 thick medium 3-5 basalt Cold, Moist

Syrupcreek 25 thick medium 2-3 basalt Cold, Moist

Mountemily 15 thick medium 10-20 basalt Cold, Moist

Troutmeadows 10 thick medium 2-3 basalt Cold, Moist

117

Limberjim 30 thick medium 3-5 basalt Cold, Moist

Mountemily 20 thick medium >8 basalt Cold, Moist

Bennettcreek 15 mixed medium 2-3 basalt Cool, Somewhat

dry

Rebarrow 10 thick medium >8 basalt Cold, Moist

Syrupcreek 5 thick medium 2-3 basalt Cold, Moist

131

Bucketlake 30 thick medium 10-20 glacial -

undifferentiated Cool, Moist

Bulgar 20 thick medium 10-20 glacial -


Mudlakebasin 15 thick medium 2-3 glacial -


Ducklake 10 thick medium 3-5 glacial -


Tyeecreek 5 thick medium 10-20 glacial -


166

Bordengulch 40 thin medium 2-3 metavolcanic and

metasedimentary rocks Cold, Moist

Threecent 25 thick medium 2-3 metavolcanic and

metasedimentary rocks Cool, Moist

Wahoogulch 15 thin medium 2-3 metavolcanic and

metasedimentary rocks Cool, Somewhat

dry

167

Honeymooncan 25 thick medium 3-5 metavolcanic and


Twobit 15 thick medium 2-3 metavolcanic and


Pasturecreek 10 mixed medium >8 metavolcanic and


168

Pasturecreek 30 mixed medium >8 metavolcanic and


Gutridge 25 thick medium 3-5 metavolcanic and


Twobit 15 thick medium 2-3 metavolcanic and


Honeymooncan 10 thick medium 3-5 metavolcanic and


216

Larabee 40 mixed medium 2-3 basalt Cool, Dry

Bennettcreek 25 mixed medium 2-3 basalt Cool, Dry

Wonder 15 thin medium 2-3 basalt Cool, Somewhat

dry

217

Klickson 40 mixed medium 3-5 basalt Cool, Dry

Larabee 25 mixed medium 2-3 basalt Cool, Dry

Bigcow 15 thin medium 3-7 basalt Cool, Somewhat

dry

256

Kingbolt, rtss 50 thick medium 2-3 pyroclastic flows Cool, Somewhat

dry

Eastpine, rtss 30 mixed medium 2-3 pyroclastic flows Cool, Somewhat

dry

266

Raycreek, mvss 50 mixed medium 2-3 metavolcanic and

metasedimentary rocks Cool, Dry

Eastlakes, mvss 30 minor medium 0.8-2 metavolcanic and

metasedimentary rocks Cold, Dry


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LTA Soil Series

Name

Soil Extent

(%) Ash Mantle

Surface

Texture

Depth to

Bedrock (ft) Parent Material Soil Climate

267

Wahoogulch, mvss

40 thin medium 2-3 metavolcanic and


dry

Hawgrose 25 mixed moderately

coarse 3-5

metavolcanic and metasedimentary rocks

Cool, Dry

Payraise 15 thin medium >8 metavolcanic and


dry

268

Wahoogulch, mvss

40 thin medium 2-3 metavolcanic and


dry

Rock outcrop 25 0 metavolcanic and

metasedimentary rocks

Blackgulch 15 minor medium 0.8-2 metavolcanic and

metasedimentary rocks Cool, Dry

317

Anatone 30 minor medium 0.8-2 Basalt Cool, Dry

Imnaha 25 mixed medium 2-3 Basalt Cool, Dry

Rock outcrop 15 0 Basalt

Bocker 10 minor medium <1 Basalt Cool, Dry

356

Wintercanyon, rtss

40 minor medium 0.8-2 pyroclastic flows and igneous intrusive with

uplift Cool, Dry

VanPatten 25 minor moderately

coarse 0.8-2

pyroclastic flows and igneous intrusive with

uplift Cool, Dry

Van Wagoner 15 minor moderately

coarse 0.8-2

pyroclastic flows and igneous intrusive with

uplift Cool, Dry


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Figure 1- Sparta project Land Type Associations and outlines of project units


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Soil depth, combined with the depth of the unconsolidated material lying over bedrock in the project area

ranges from very shallow (about a foot) to over ten feet. The surface soil layer is the layer that supports

the root zone for fine and medium size roots.

Soils with an ash mantle commonly have a different surface texture than the material buried beneath the

ash. Typically, soil textures in the project area are silt loams with varying rock content. Subsurface

layers in the project area are generally rockier than surface layers. Source material for soils includes

basalts and other volcanic rocks, meta-sedimentary rocks, and glacial deposits.

Project Area LTA Descriptions

The majority of the treatment units are located within the following LTAs. This is a partial list of LTAs

that describes the dominant soil features within selected LTAS. The descriptions are listed here to

provide more background on dominant features of soils in LTAs in the project area. The soil information

provided is for the dominant soil series in each LTA. Soil erosion hazard ratings for each soil series are

reflected in LTAs

Landtype 116

This LTA consists of andesitic and Columbia River basalts with gentle sloping hills and plateau surfaces

with less than 30% slope and supports moist forests with some dry forest and dry grass. This LTA covers

923 acres, or about 16% of the treatment units. The dominant soil series is a deep silt loam ash that

occurs on stable ridgetops and sideslopes of the plateaus and the backslopes of mountains.

Major Soil Series

Soil Depth

Surface (0 to 10”)

Surface Texture

K factor

Bulk Density

Drainage Class

Erosion Hazard Rating

Limberjim 40-60 Gravely Silt loam .24 .65 - .85 Well Low

Landtype 216

This LTA consists of andesitic and Columbia River basalts with gentle sloping hills less than 30% slope

and supports dry forests with some portions of dry grass and dry shrubs. This LTA covers 1,001 acres

(approximately 17%) of treatment units. This soil is a moderately deep ash soil that occurs on the

backslopes of mountains.

Major Soil Series

Soil Depth

Surface (0 to 10”)

Surface Texture

K factor

Bulk Density

Drainage Class


Bennetcreek 20-40 Silt loam .24-.37 .75-.95 Well Low

Landtype 256

This LTA consists of metasediments on gentle sloping hills with less than 30% slope and supports dry

forests and dry forests with some portions of dry grass. This LTA covers 968 acres (approximately 17%)

of treatment units. The major soil series associated with this LTA are Kingbolt and Eastpine soil series.

These series are frigid (cold) and xeric (dry) soils. The Kingbolt series consists of moderately deep, well-

drained soils on ridges, benches and shoulders of mountains. Kingbolt soils are formed in ash overlying

colluvium and residuum from argillite or other metasedimentary, metavolcanic or rhyolitic

bedrock. Eastpine series consists of moderately deep, well drained soils on ridges, shoulders, and

backslopes of mountains. Eastpine soils are form in colluvial and residual material derived from

metasedimatary rocks with an influence of volcanic ash.


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Major Soil Series

Soil Depth

Surface (0 to 8”)

Surface Texture

K factor

Bulk Density

Drainage Class


Kingbolt

Eastpine 0-40

Ashy silt

loam .28-.55 0.65-1.0 Well Low-Mod

Landtype 266

This LTA consists of metasediments on gentle sloping hills with less than 30% slope and supports dry

forests and dry forests with some portions of dry grass. This LTA covers 2166 acres (approximately

38%) of treatment units. The major soil series associated with this LTA was Kamela and Anatone and the

table below is a combination of the two dominantly Anatone combined with Kamela characteristics. This

soil is a moderately deep rocky loam with an ash influence that occurs on ridgetops and sideslopes of

mountains.

Major Soil Series

Soil Depth

Surface (0 to 8”)

Surface Texture

K factor

Bulk Density

Drainage Class


Kamela (Anatone)

30 Gravely

loam .10-.15 1.2-1.7 Well Mod

Soil Impact Surveys and Erosion Risk

Surveys of soil disturbance in 2008-2010 and 2016 conducted by the project soil scientist showed that soil

conditions from past vegetation management and other activities are in recovery from past and on-going

impacts. Units were selected from throughout the project area to obtain a representative sample of project

units proposed primarily for ground-based treatments based on the amount of treatment acres and soil

characteristics. Past management activities included timber harvest, fuelwood cutting for personal use,

livestock grazing, soil effects associated with noxious weed treatments, road use, recreation activities, and

past wildfire.

Most project units have a history of land use, and evidence of past timber harvest was common. Surface

erosion or recent slope instability was not evident in the project area outside of roads and trails, but many

existing roads showed signs of surface erosion and rilling. Residual soil disturbance such as old skid

trails and landings were observed in treatment units, but much of the soil disturbance from past activities

was recovering. Soil disturbance and detrimental soil conditions survey results are provided later in this

report.

Soil erosion ability is a function of detachability, infiltration rate, permeability of lower soil horizons,

uniformity of slope and slope percent, water concentration potential, distribution of annual precipitation,

rainfall intensities, soil temperatures, and the depth and density of effective ground cover following

disturbance. Soil erosion is a natural process that can be accelerated by land management activities.

Soils on steep slopes with poor vegetative cover are more susceptible to erosion than are soils on flatter

terrain. Vegetation, and the duff and litter protect the soil surface from raindrop impact, dissipates the

energy of overland flow, and binds soil particles together. From resource surveys done by the project soil

scientist existing established ground cover is over 60% in most areas within the project, helping to protect

against surface soil erosion.

Table 2 shows the sedimentation properties and response of soils in the project area. From TEUI surveys

it was found erosion risk varied by LTA, ranging from low to high for disturbed sites, and mostly low to


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medium risk for undisturbed sites. The treatment area used for this discussion is for treatment proposed

in Alternative 2, which represents the largest area of proposed treatment. The majority of the project area

units (51%) are in the low sediment delivery efficiency range with 88% in the low-low/medium sediment

delivery efficiency range. Sediment erosion efficiency is the relative efficiency of landforms to route

eroded debris into first order stream channels and deliver sediment into mainstem streams. The factors

used to rate LTAs for sediment delivery efficiency are: surface runoff response, slope gradient and shape,

low order stream density, stream channel geomorphic type; position in the watershed in terms of distance

to a mainstem perennial channel; and potential for shallow rapid landslides. Low risk areas for sediment

delivery efficiency can absorb a great deal of surface water before individual soil particles are detached.

Surface runoff normally is well dispersed and does not become concentrated in first order streams. These

LTAs limit surface water and sediment from being routed quickly to first order stream systems. As a

result, first order stream catchment basins do not have evidence of rilling and channels do not have a

history of scour or non-vegetated deposition. Normally these Landtype Associations do not have a

history of shallow rapid landslides being delivered into mainstem streams. In summary LTAs in the low

range for sediment delivery efficiency have a set of the following site features: low slope gradients

<25%, more than 80 percent vegetation cover; deep, moderately coarse textured subsoils; very little

exposed bedrock; low drainage density for first order streams; and the area is not normally exposed to

rain-on-snow events or high intensity rainstorms. Landtype Associations with moderate sediment

delivery efficiency represent 29% of treatment units. These have a set of the following site features:

slope gradients between 25 and 45 percent; vegetation cover is 30 to 80 percent; sub-soil depths that vary

from shallow to moderately deep; exposed bedrock is less than 25 percent of the area; moderate drainage

density of confined or entrenched first order stream systems with both source and transport stream types;

area exposed to infrequent rain-on-snow events or high intensity rainstorms.

About 30 acres or less than 0.7% of tractor or skyline system logging are in the high sediment erosion

efficiency areas. In contrast to low-ranked areas, these landscapes do not absorb a great deal of surface

water before individual soil particles detach. These Landtype Associations have a set of the following

site features: steep slope gradients (45%+); less than 30 percent vegetation cover; shallow subsoils;

exposed bedrock exceeds 25 percent of the area; high drainage density of confined or entrenched first

order streams; and the area is exposed to frequent rain-on-snow events or high intensity rainstorms.

Surface runoff in these areas is poorly regulated and concentrated flows are routed rapidly into first order

drainages, and they are extremely efficient in routing surface water and sediment into first order stream

systems. Slope shapes are less complex with few breaks in grade to offer slope storage of eroding debris.

First order catchment basins have evidence of past rilling and stream channels have evidence of scour or

non-vegetated deposition. Normally these Landtype Associations have had a relatively frequent history

of shallow rapid landslides or high incidence of colluvial material delivered directly into mainstem

streams.

Units 4, 54, 66, 67, and 81 all have high sediment delivery potential and are either tractor and/or machine

pile units. Units 32, 48, 87, 91, 92, 96, 104, 115, 117, 118, 113, 140 and 152 all have high risk for soil

erosion when disturbed and are either tractor and/or machine pile units.

Table 2. Sedimentation Properties and Response.

LTA

Total Treatment Unit Acres

(Tractor, Skyline, RX Burn)

Sediment Delivery

Efficiency

Soil Erosion Risk

(Disturbed Sites)

Soil Erosion Risk

(Undisturbed Sites)

Landslide Risk- Deep-

Seated

Landslide Risk-

Shallow-Rapid

116 923 L L-M L L L

117 186 M H L L-M M

131 45 L L-M L L-M L

166 15 L L-M L L L


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LTA

Total Treatment Unit Acres

(Tractor, Skyline, RX Burn)

Sediment Delivery

Efficiency

Soil Erosion Risk

(Disturbed Sites)

Soil Erosion Risk

(Undisturbed Sites)

Landslide Risk- Deep-

Seated

Landslide Risk-

Shallow-Rapid

167 205 M H L L-M M

168 30 H H M M-H H

216 1001 L L-M L L L

217 13 M H L-M L L

256 968 L L-M L L L/L

266 2166 L-M M L-M L L

267 138 M H M L-M M

268 37 H H M-H M H

317 45 M M-H M L L

356 3 L M L-M L-M L

Mass Wasting in Project Area

Slopes over 40% are at higher risk for landslides, and have been evaluated for landslide risks during TEUI

surveys and by observations during site surveys. Generally the project area is a stable landscape and the

potential for new landslides to occur is relatively low. The soils in the project area have been evaluated

for deep seated landslide potential and for shallower, rapid slides on slopes over 40%, and the risk ratings

are mostly in the low to medium risk range (Table 2). Some terrain is “hummocky”, indicating old healed

deep-seated landslide deposits, but no recent mass failures such as slumps or debris flows were found,

even though much of the area has been previously harvested. Most sites are in the low to medium risk

range for shallow, rapid landslides such as debris flows. Old landslide landforms are noted within the

project area, especially on the east side of the project area. However, none appear active and none appear

to be caused by past land management. There is evidence of very slow soil creep in steeper inner gorge

areas, especially in the Little Eagle Creek drainage, but no evidence of recent larger scale mass soil

movements were observed. Triggers for movement would likely include above average

precipitation/snowpack and earthquakes. The most unstable areas in the analysis area are found on 67

unit acres in LTAs 168 and 268. These areas have a more “flashy” response to precipitation events that

can elevate the risk of debris flows.

Sparta Soil Productivity

Soil productivity of a site is defined as the ability of a site to produce vegetative biomass, as determined

by conditions (e.g. soil type and depth, rainfall and temperature) in that area. Productivity is the capacity

or suitability of a soil for establishment and growth of plant species, primarily through moisture and

nutrient availability. The long-term productivity of forest soils can be adversely affected by removal of

nutrients and alterations in soil structure such as compaction. Removal of nutrients can occur through the

removal of vegetation (i.e. trees, shrubs and grasses), erosion, and preparation of sites for treatment and

burning. Long term soil productivity of forested ecosystems relies on a continual flux of coarse woody

material. Important nutrients to the soil ecosystem, such as carbon, sulfur, phosphorus and nitrogen, are

supplied by decaying coarse woody material (CWM, Graham 1994). Timber harvest, slash disposal and

site preparation can reduce the amount of organic material in the forest floor to below what is needed to

ensure soil productivity (Harvey et al. 1987).

Soil nutrients are primarily replenished through the decomposition of organic matter such as litter, duff,

coarse woody debris, and root turnover (Benson, 1982). Organic matter (surface litter and duff) depth

was commonly observed to be 1-4 inches within the Sparta project area. Ground cover, generally

consisting of matted pine grasses, heartleaf arnica, woods strawberry, common snowberry (in warm/dry

habitats), big huckleberry, prince’s pine and twin flower (cool/dry habitats), and shade tolerant conifer

seedlings, is well established in the disturbed areas within the forested portions of the units. On the


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droughty scab soils in forest openings, lichens, mosses, and to a lesser extent pine grass leaves and

crowns account for a high proportion of the surface litter. Biological soil crusts exist in some forest

openings. Amounts of coarse woody material (CWM over 12 inches in diameter at the small end and at

least 6 feet in length) are low across the units. Potential future down wood recruitment from standing

dead trees depends upon their location relative to firewood cutting access.

Soil Compaction and Displacement

In the Sparta project area soil compaction is a primary disturbance factor affecting soil productivity.

More information on the effects current management is having on project area soils is provided in the No-

Action alternative discussion in the Effects section of this report. Skid trails, landings and non-surfaced

roads, ATV trails, livestock trails and dispersed campsites all have led to increased soil compaction and

bulk density throughout the project area. Visual surveys by the project soil scientist in 2008-2010 and

2016 indicated vegetation re-growth and biological activity is breaking up some of the surface

compaction (0-4 inches) of soil on the historic skid trails and closed roads.

Soil displacement is the movement of soil from one place to another by mechanical forces and is typically

associated with roads, landings, and skid trails. Effects include reduced water holding capacity, loss of

ground cover, nutrients and soil microorganisms, and increased runoff due to an increased amount and

condition of bare ground exposed (Page-Dumroese et al 2006). Some displacement has occurred in most

surveyed units. This form of disturbance was evident where machinery had sharply turned or where

previous harvesting had occurred during periods of wet or moist soil conditions. Steeper slopes are more

vulnerable to soil displacement. During resource surveys, locations where surface soil displacement had

occurred in the past were often revegetated with a high percent of ground cover.

Table 3. Sparta Project Land Type Associations and Treatment units for the Proposed Action (Alternative 2) showing acres and percentages of project area within each LTA (source-project GIS information). Units are both ground-based and skyline harvest, or proposed as prescribed burns.

Landtype Total Unit

Acres

Percent %

Treatment Units

116 923 16 93, 95-97,101,102,108,113,122,124-148

117 186 3 84-87,91,92,94-97,99,100-105,132,133,139-141,

131 45 <1 2-5

166 15 <1 128,151,152

167 205 4 05-07,20,21,21A,22-28,28A,29-32,47-49,55,81,152

168 30 <1 01,04

216 1,001 17 01,08,09,11-20,21A,22,36,75-86,88,89,89A,90-93,99,103-107,113,114,116,120,122-126,149,150,153

217 13 <1 87,88

256 968 17 52,53,57-67,73,74

266 2,166 38 11-14,27,31-45,45A,46-48,50-55,65-67,69,73,74

267 138 2 114-119

268 37 <1 54,55,66,67,69,73

317 45 <1 81,106-113

356 3 <1 61


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Table 4 shows the hydrologic properties of soils in LTAs for the project area. Numerous intermittent

tributaries and ephemeral swales were found within the project area. A few channels have been logged,

used as skid trails, and grazed. Un-channelized swales or ephemeral draws exist throughout the project

area. Despite the past logging and skidding operations, the swales have good re-establishment of

vegetation and ground cover and in most cases are not showing signs of channel development.

Table 4. Hydrologic properties of soils in the Sparta Project area by LTA.

LTA Total Treatment

Unit Acres Surface Runoff

Channel Density

Stream Flow Duration

Stream Flow Amount

Aquifer Recharge

116 923 Low Low Intermittent Occasional storm flow Low

117 186 Moderate Moderate Intermittent or

Perennial Low flow Low

131 45 Low Moderate Perennial High flow Moderate to High

166 15 Low Moderate Intermittent Occasional storm flow Low

167 205 Moderate Moderate-High Intermittent or


168 30 Moderate High Intermittent Low flow Low

216 1,001 Low Low Intermittent Occasional storm flow Low

217 13 Moderate Low-Moderate Intermittent or



266 2,166 Low Moderate Intermittent Occasional storm flow Low

267 138 Moderate Moderate-High Intermittent or


268 37 Flashy High Intermittent Low flow Low

317 45 Moderate Low-Moderate Intermittent Low flow Low


Mean annual precipitation averages 20 to 40 inches per year, primarily in the form of snow with some

spring and fall rains and summer storms. Surface runoff ranges from low to moderate in the project area.

LTA 268 has flashy flows, with high flow peaks that diminish quickly. Channel density in units ranges

from low to moderate. Aquifer recharge through soils in the project area is considered low except in LTA

168. The major soil complexes represented within the analysis area exhibit moderate permeability rates

and in upland areas are mostly well drained.

Past and On-going Vegetation Management Projects

Several vegetation management projects have been completed in portions of the project area over past

decades. Historically, the majority of the project units were conventionally logged (utilizing both rubber

tired and tracked skidders) and hand felled. Multiple entries over many decades for timber harvest and

other purposes have occurred, and residual soil disturbance is wide spread in extent. Much of the past

timber harvest in the Sparta area selected larger individual trees for removal. For older harvest methods,

skid trails often were not pre-designated and as a result were randomly distributed throughout the old

units. Main skid trails were spaced approximately 50 to 100 feet apart. Evidence of old compaction


14

(platey sub-surface soils) is currently being reduced by the established root systems of vegetation and

rodent burrows. During resource surveys, it was commonly observed that exposed mineral soil was low

along re-vegetated skid roads; and old skid trails typically had a high percent of ground cover. Re-

vegetation on old skid trails helps break up compaction through root penetration. Old landings from

previous harvest in many areas were re-vegetating, with some evidence of reduction in soil compaction.

However, in most cases, skid trails and landings represent the greatest amount of legacy compaction in

the project area.

Detrimental Soil Conditions (DSCs)

Currently, detrimental compaction and puddling exist primarily on landings and skid trails. Detrimental

compaction and puddling also exist at dispersed campsites and on major livestock/wildlife trails.

Compaction and puddling adversely affect infiltration rate, water holding capacity, soil microorganisms,

plant cover (including biological soil crusts), and plant roots. Annual cycles of activity by large grazing

animals, campers, and vehicle and equipment operators can re-compact roads, trails and campsites.

Detrimental displacement persists on all roads (top of cut to bottom of fill), landings, major skid trails,

borrow areas, old ditches, and at landslides. Detrimental displacement adversely affects all soil properties

and characteristics, including but not limited to topsoil thickness, soil depth, water holding capacity,

ground cover, woody debris, fertility, infiltration, permeability, and soil microorganisms.

Severe burning occurs under firepits at campsites, under/around partly decomposed logs and stumps that

burn during prescribed fire and wildfire, and under hand piles, grapple piles and slash piles that are

burned. No severe burning or detrimental burn effects were found in the analysis area. Light to moderate

intensity wildfire can reduce organic matter by consuming litter, duff and rotten logs, but can also cause

new inputs of organic matter through increases in litter fall. These conditions are not detrimental to soils.

Moderately high to high intensity wildfire would greatly reduce organic matter on the soil surface, which

would increase potential for detrimental erosion, but would provide large inputs of coarse wood over

several decades.

Surface erosion was primarily observed on road surfaces or fill slopes, primarily due to heavy rainfall or

snowmelt. Types of erosion included sheet, rill and gully erosion. Organic matter loss exists on roads,

trails (once used as roads), skid trails, landings, landslide scars, old wildfire areas, and pockets of low

ground cover shallow-soil rangelands in lower elevation areas in the southern part of the project area.


15

Table 8. Existing detrimental soil conditions in project area at representative ground-based harvest units.

Sparta

Ground-based acres

(except where noted)

Latest past harvest

year

Litter/duff (in)

Coarse Woody Debris

(per acre)

DSC's (%)

4 24 unknown 4

7 7 unknown 4

12 106 1979 5

13 10 1979 3

14 85 1979 3

18 24 1979 3

32 119 (F) unknown 2/0 0 4

34 78 (F) 1993 1/0 0 4

35 46 (F) 1993 1/0 0 4

36 125 (F) 1979 4

38 122 1996 1/0 1 4

40 14 (F) 2001 4

41 139 (F) 1993 2

43 200 (F) 1993 2

45 90 2001 3

46 176 (F) 1993 2

48 34 unknown 2/0 0 4

50 31 1989 3

52 89 (GP/RXF) 2001 1/0 0 3

53 108 2001 1/0 0 3

61 6 (RXF) unknown 1/1 1 4

62 97 (RXF) unknown 1/1 1 4

73 252 (RXF) unknown 1/0 1 2

74 137 (RXF) unknown 1/0 1 2

81 144 1987 1/1 1 4

89 27 1993 5

90 13 (S) 1993 1/1 1 4

91 32 1993 5

107 15 1987 1/0 1 5

118 39 1993 4

119 8 (S) 1993 4

125 41 1987 3

129 55 1987 1/2 1 4

131 54 (F) 1987 1/2 1 4

134 43 (F) 1993 5

139 10 (S) 2001 6

152 8 2000 1/2 2 6 F = Forwarder yarding GP = Grapple Piling RXF = Prescribed burning S = Skyline yarding

Effects

Introduction

Direct effects happen at the time and place of the action. Soil compaction or displacement is a good

example. When a skidder travels over wet ground and compacts or displaces soil, a direct effect may

result. Indirect effects happen later in time or a different place, such as soil erosion resulting from a

management activity. Indirect effects happen when the soil surface is disrupted, but soil loss does not


16

occur until a storm event at some later time. Cumulative effects consider an activity area (timber harvest

unit), and assess all past, present and reasonably foreseeable future activities to determine the total impact

of all activities that overlap in time and space. Cumulative effects can be both positive and negative.

Effects on soils from a project may be positive or negative. Effects may include alteration of physical,

chemical, and/or biological characteristics or properties of soils. Standards and guidelines in the Forest

Plan (1990) are designed to protect soil function, soil productivity, and soil stability.

The most adverse effects of management activities on soils are detrimental compaction, puddling,

displacement, severe burning over larger areas, erosion, and mass wasting. Other concerns include

adverse changes in vegetation and organic matter on the soil surface, and adverse changes in water table

(USFS 1998). Soil compaction, puddling, displacement, severe burning, and impacts to ground cover

(vegetation and organic matter) are direct effects; soil erosion, mass wasting, and changes in water table

are indirect effects. Cumulative effects are the sum of incremental changes in past, present, and

reasonably foreseeable future direct/indirect effects on the soil resource that overlap both in time and

space.

Methodology and Assumptions

Management activities can result in direct, indirect and cumulative effects on soil productivity and soil

stability. The focus for this analysis of effects is the condition of soils within project units. The bounds

of analysis for determining direct, indirect and cumulative effects of the project’s activities on the soil

resource are the project units. This area was selected because direct and indirect effects to soils that

would occur where management is proposed to take place and are not expected to extend outside the

project unit boundaries. The temporal bounds for this analysis can be decades, however most detrimental

soil impacts from this project will begin recovery after project activities are complete.

The magnitude of the effects of an activity on soil productivity and soil stability depend on the extent and

patterns of change due to management activities. Minimizing productivity losses associated with any

action can be accomplished by managing the extent of detrimental soil conditions within activity areas

through treatment prescription and/or mitigation. Planned management activities must minimize new soil

damage and must provide for soil restoration measures when and where they are appropriate (Forest Plan

1990, Soils Standard & Guides).

Resource surveys were conducted in 2008-2010 and 2016 to determine detrimental soil disturbance

(DSCs) for soils in treatment units. The results of these surveys are shown in Table 8. For current

conditions, soil quality is being maintained in at least 80% of the area of each proposed activity unit as

required by Region and Forest Plan standards. The features of detrimentally disturbed soils are shown in

Table 7. The protocol for determining detrimental soil conditions based on field soil conditions (Howes,

2001) is listed in the Appendix and is briefly described here.


17

Table 7. Features of detrimentally disturbed soils (Howes 2001)

Detrimental Soil Conditions (DSCs): Soil Effects Models

Soil DSCs were determined for the Proposed Action. To be compliant with the Forest Plan, project

implementation must minimize post-project DSCs so they do not cumulatively exceed 20% within an

activity area. Other impacts like vegetation removal may have a cumulative impact on soil cover or

coarse woody material needed as a long-term source of soil nutrients.

Soil quality conditions were assessed in proposed timber harvest units using the Interim Protocol for

Assessment and Management of Soil Quality Conditions (Howes, 2001). Detrimental soil conditions

were determined by the transect method (Howes, 2001). For these assessments, each project unit

represents an activity area. Units were selected from throughout the project area to obtain a

representative sub-sample of project units proposed for mostly ground-based treatments based on soil

characteristics, past harvest amounts, and the amount of unit acreage. Sampled units were thought to

represent typical conditions for project units. In areas with non-existent or low (0-5%) adverse soil

conditions, a level 1 survey estimate of detrimental soil conditions was made in selected units to the

nearest percent based on unit conditions.

The contribution to DSCs from roads within harvest units was calculated and added in to the DSC

calculation by converting road mileage to road acreage, consistent with DSC calculation protocols

(Howes 2001). Road mileage was determined for National Forest administered land in the analysis area

using GIS roads information. For DSC calculations, GIS road mileage for each proposed harvest unit and

prescribed fire unit was adjusted by excluding all roads that were adjacent to the units unless they were

shared between units. Road mileage was converted to road acreage. Road mileage data for units was

converted to acres using the formula, [(miles) times (acres/mile) = acres]. Soil resource surveys focused

on areas containing ground based harvest units from prior projects because effects of past harvest were

expected to be greater in these units. Also, projected effects of the Proposed Action on soils will be

higher for tractor, ground-based logging systems.

Predicted soil DSCs generated by action alternatives were developed using soil effects models developed

by soil scientists on the Wallowa-Whitman National Forest to describe effects of various types of forest

Class 2: Moderate Disturbance

Soil surface:

Wheel tracks or depressions are >6” deep.

Litter and duff layers partially intact or missing.

Surface soil partially intact and may be mixed with subsoil.

Burning consumed duff layer, root crowns, and surface roots of grasses. Surface soil is blackened.

Soil resistance to penetration with tile spade or probe:

Increased resistance is present throughout top 4-12 inches of soil.

Observations of soil physical conditions:

Change in soil structure from crumb or granular structure to massive or platy structure, restricted to the surface 4-12 inches.

Platy structure is generally continuous.

Large roots may penetrate the platy structure, but fine and medium roots may not.

Class 3: High Disturbance

Soil surface:

Wheel tracks or depressions highly evident with depth being >12” deep.

Litter and duff layers are missing.

Evidence of topsoil removal, gouging and piling.

Soil displacement has removed the majority of

the surface soil. Surface soil may be mixed with subsoil. Subsoil partially or totally exposed.

Burning consumed duff layer, root crowns and surface roots of grasses. Evidence of severely burned soils (mineral surface soil red in color)

Soil resistance to penetration with tile spade or probe:

Increased resistance is deep into the soil profile (>12 inches).

Observations of soil physical conditions:

Change in soil structure from granular structure to massive or platy structure extends beyond the top 12 inches of soil.

Platy structure is continuous.

Roots do not penetrate the platy structure.


18

management on soils. The effects models provide a reasonable estimate of direct and indirect effects of

project activities on soils, with the results expressed in increased DSCs generated by each treatment type.

These effects of forest management may be less or more pronounced in units located in different LTAs,

depending on sensitivity.

For this analysis, and the model application, it is assumed that the soil response to management impacts

will be similar across different LTAs. Topographic factors, local soil texture, rock content, and hillslope

stability and other factors all play a role in management response of soils, and influence the effectiveness

of soils effects models for predicting DSCs. The models use information from post-project monitoring of

different types of activities to estimate the amounts of DSCs generated by forest treatments (Bliss 2001,

2003, 2004). They have been used extensively in environmental analysis of soils for past forest projects.

Predicted DSCs are based on the effects model for each type of treatment proposed. DSCs were

calculated for each unit where soil resource surveys were done to determine the extent of post-project

detrimental soil conditions (Table 11).

Soil Effects Model Assumptions

Summary of Effects Models:

Ground-based Harvesting Effects Model: 10-20% ground disturbance, with 6-12% new

DSCs.

Skyline Yarding Effects Model: 10-25% ground disturbance, with 0-1% DSCs.

Temporary Road Construction Effects Model: 3.0 ac/mile DSCs.

Grapple Piling Effects Model: 5-8% ground disturbance, with 1-2% DSCs.

Grapple-Piled Slash Burn Effects Model: 1-2% DSCs.

Landing Slash Burn Effects Model: 0.5-1% DSCs.

Hand-Piled Slash Burn Effects Model: 0-1% DSCs.

Underburn Effects Model: 0-4% severe burn, but no DSCs.

Ground-based Harvesting Effects Model Harvesting effects estimated by this model are primarily soil compaction and displacement, and minor

amounts of puddling. Local data (Bliss 2003a) indicate new ground-based yarding activities would

disturb about 10-20% of the ground surface, with about 5-10% DSCs per unit before implementation of

any mitigations. These results are based on past monitoring which shows that about 50% of skid trail

width has been observed to be detrimentally compacted and displaced. It is assumed that landings would

occupy about 1-2% of a unit. The effect of skid trails plus landings for tractor/yarder harvest systems

would generate 6-12% new DSCs. The range of possible effects is wide due to several variables

including type of harvest equipment used, operator skill, layout, current infrastructure, past harvest

effects, landform characteristics, and soil site conditions. New DSCs would be lower in units with DSCs

from previous entries because old skid trails and landings that are detrimentally disturbed from past

harvest can be re-used. Based on conditions in Sparta units, 10% DSCs are assumed to be generated by

ground-based logging, including skid trails and landings. In units with RHCAs, where

processor/forwarder harvest systems are proposed to be used to cross RHCAs, DSCs are estimated to be

4-6%. Processor forwarder effects are less because they use wider tires with less ground pressure, and

operate on slash, which helps reduce soil compaction and displacement.

Skyline Yarding Effects Model The effects of skyline yarding are based on definitions of detrimental compaction and displacement in

Howes 2001. Yarding effects would be primarily soil displacement. Landings are typically spaced about

200 feet apart. Trees would be directionally-felled towards one or two skyline corridors. Logs would be

yarded with one end suspended and limbs attached. Limbs would be removed and piled on hillslopes

adjacent to landings. Each tree would produce 2-4 logs. Logs would be yarded with tops attached. The


19

largest logs would have few to no limbs. Local data (Bliss 2004c) indicates yarding would disturb 10-

25% of the ground surface, and leave 0-1% new DSCs in each unit. Whole-tree yarding and good ground

cover widely found in the project units consisting of elk sedge-pinegrass or shrubs help moderate the

effects to soils. Most soil displacement would be less than 2 inches deep.

Grapple Piling Effects Model The effects of grapple piling are based on definitions of detrimental compaction and displacement in

Howes 2001. The equipment to be used for grapple piling of woody debris would be a low ground

pressure (5-6 psi) tracked excavator with a grapple on a 25 to 30-foot long boom from the center of the

vehicle. The tracks would consist of metal cleats. Normal use would track a maximum of about 8% of a

treatment unit. Where fuels are less dense, less of the unit would be tracked. Total ground disturbance

would be about 5-8%, with an estimate of 1-2% DSCs (Kreger 2004). Actual DSCs would be affected by

variables such as soil density, percent rock in/on the soil surface greater than 3 inch diameter, soil

moisture, ground cover (vegetation type and woody debris tonnage), type of equipment used, and operator

skill.

Grapple-Piled Slash Burn Effects Model Burn effects are based on definitions in Debano et. al. 1998 and USFS 1998. Pile burn effects qualify as

detrimental soil conditions if they are severe burns and occupy an area of at least 100 square feet (USFS

1998). Local data from past projects in a similar area (Hanson 2005) indicates grapple piles would

occupy 1-2% of units (4 to 7 piles/acre up to 12 feet in diameter) and are typically more than 100 square

feet. The range of effects from grapple piling and burning these piles would be 1-2% DSCs.

Landing Slash Burn Effects Model Landing slash burn effects are based on definitions in Debano et. al. 1998 and USFS 1998. Pile burn

effects qualify as detrimental soil conditions if they are severe burns and occupy an area of at least 100

square feet (USFS 1998). Local data (Bliss 2004c) indicates slash piles at skyline landings are typically

100-1000 square feet in size (11-36 feet in diameter). When burned, these piles would cause about 0.5-

1.0% DSCs. Slash piles in ground-based units can be larger, however DSCs from pile burning at landings

would be in the same range.

Hand-Piled Slash Burn Effects Model Burn effects are based on definitions in DeBano et. al. 1998 and USFS 1998. Pile burn effects qualify as

detrimental soil conditions if they are severe burns and occupy an area of at least 100 square feet (USFS

1998). Local data (Bliss 2003a, Bliss 2004c, Hansen 2005) indicates that most of the area under hand-

piled burn piles would qualify as severe burn effects, and that burn piles typically occupy 1-4% of the

ground surface but are usually less than 100 sq. ft (11.3 feet in diameter). Therefore, pile burning would

cause only 0-1% DSCs.

Underburn Effects Model Burn effects are based on definitions in DeBano et. al. 1998 and USFS 1998. Underburn effects qualify

as detrimental soil conditions if they are severe burns and occupy an area of at least 100 square feet

(USFS 1998). Local data (Bliss 2003a) indicates there would be 0-4% severe burn effects in prescribed

fire underburn areas, but no DSCs because severe burn areas would be under 100 square feet. Prescribed

fire usually results in a mosaic of low, moderate and high fire severity that is classified mostly as low

severity burn class. Severe burn effects typically occur adjacent to and under logs and in burned out

stump holes. Underburn effects may range from low-severity burn class to high-severity burn class, but

do not qualify as detrimental soil conditions. Low severity burn areas typically exhibit a relatively minor

risk of increased erosion. The risk increases substantially in moderate to high severity burn areas, which

usually occupy a very limited amount of ground in prescribed burns.


20

Mitigations

The effects analyses in this report are based on full implementation of the following mitigation measures

and project design criteria for the Sparta project.

The mitigating measures listed below will be implemented to meet the standards in the Land and

Resource Management Plan (LRMP) of the Wallowa-Whitman National Forest. Best management

practices (BMPs) are forest management practices designed to prevent the degradation of forest lands and

water quality during and after timber harvest. Forestry BMPs have been shown to be effective at

controlling sediment, erosion, and nutrients from forest management activities (Lynch and Corbett 1990;

Stuart and Edwards 2006).

These standards state:

Minimize detrimental soil conditions with total acreage impacted (compaction, puddling,

displacement, and severe burning) not to exceed 20 percent of the total acreage within the project

area including landings and system roads. Also see PDF below on width between skid trails.

The Plan requires use of "approved skid trails, logging over snow or frozen ground or dry soils, or

some equivalent system for limiting the impact and aerial extent of skid trails and landings and to

prevent cumulative increases from multiple entries in tractor logging areas.

The following guidelines from The Watershed Management Practices Guide for Achieving Soil and

Water Objectives for the Wallowa-Whitman National Forest (Hauter and Harkenrider 1988) as adapted,

are applicable to this planning area:

Width between skid trails: Maintain a minimum of 60 feet between main skid trails to the extent

possible. The distance may be greater depending on the type of equipment being used and site

conditions.

Soil Moisture: "Under saturated soil conditions no off-trail skidding or machine falling is

allowed. Skidding on designated trails may be allowed as long as such use does not cause deep

rutting causing erosion damage, or erosion damage potential. Allowing skidding under these

conditions makes mitigation by subsoiling/scarifying less effective and should be avoided both on

and off trails." Existing skid trails will be used as much as possible.

Subsoiling/Scarifying: Skid trails and landings will be evaluated for the need for

subsoiling/scarifying following treatment by the sale administrator and district watershed

personnel. Sub-Soil treatment will be determined by the district resource specialists and based on

soil depth and characteristics. Sufficient woody material will be left to maintain long term site

productivity. This recommendation specifies a minimum of 10 tons per acre of woody material

greater than 3 inches in diameter.

1) Subsoil to a depth of 20-24 inches on multiple pass skid trails and all landings.

Equipment to complete subsoiling may include:

a) Use of a winged ripper with triggered tines to allow for more effective subsoiling

in stony soil. Discontinue subsoiling where large rocks are continually brought

to the soil surface, or operate with the shoes at a shallower depth (15 inches).

b) Use of a tracked excavator with subsoiling tines.

2) Scattering of organic matter to provide a minimum of 50% effective ground cover.

3) Seeding with native seed to facilitate vegetation recovery

Water Bars- Construct water bars on skid trails and firelines where soil disturbance is evident (and at the

direction of the administrator), using the spacing guide below:


21

Gradient Spacing

Under 20 % 80 ft.

20 - 39 % 40 ft.

Greater than 40 % 25 ft.

Construct waterbars on all temporary roads per standard gradient-related spacing guidelines (see

Hauter & Harkenrider 1988, p. 47).

Construct waterbars on erosion-sensitive sections of roads, where pre-project erosion has and will

continue to damage the road surface.

Construct 3-inch deep diagonal hand-dug waterbars (6 inches deep from bottom of trough to top

of berm) (using standard gradient-related spacing guidelines) along any skyline corridor where

dragging logs bared any area to mineral soil longer than 30 feet lineal distance (Hauter &

Harkenrider 1988). This work must be done before the unit is underburned, because erosion

hazard will increase after the unit is underburned.

Use lower ground pressure harvest and yarding equipment

Maximize use of old skid trails and old landings.

Seed roads, landings, and skid trails after logging is completed, as needed, with site-specific seed

mix, for erosion control. Consider using waterbars and slash on skid trails.

No Direct, Indirect, or Cumulative Effects

The following activities in the action alternatives would have a negligible potential to effect soils

resources:

Danger tree removal

Snag Retention

Snag Creation

Right-of-way acquisition

These activities will not be discussed further in this analysis.

Direct and Indirect Effects

Alternative 1 Under Alternative 1 current management would continue. There would be no additional ground

disturbing activities or vegetation removal; therefore, there would be no potential for increasing

detrimental soil conditions above the existing levels.

Soils conditions in the project area reflect past impacts from vegetation management including timber

harvest, road use and maintenance, livestock grazing, fuelwood cutting, activities associated with noxious

weed treatments, recreation activities including camping, All-Terrain Vehicle (ATV) use, snowmobile

use, use of trails, and past wildfire (Table 5). Direct and indirect effects to soils from these activities

would persist under this alternative. The following discussion describes the effects of current conditions

with a focus on past and on-going management activities that can affect soils.

Table 5. Summary of past and on-going activities, Sparta Project. These projects all contribute to direct and indirect effects on soils.

Alternative 1- No Action

Recent Past and Ongoing Actions

Vegetation Management and Timber Harvest.

Livestock Grazing (3 allotments).

Fuelwood Cutting (annually).

Noxious Weed Treatments along open roads (annually).


22

Alternative 1- No Action

Recreation: camping, ATV use, use of trails to wilderness (annually).

Foreseeable Future Actions (in next 10 years):

Private land development adjacent to project units.

Past Vegetation Management Projects

The effects of soil disturbance on soil productivity and the duration of adverse effects largely depend

upon the type and extent of disturbance. Disturbances such as roads and ditches generally are permanent

because the soil structure is severely altered during construction. Compaction resulting from tractor

yarding can potentially last for several decades (Froehlich and McNabb, 1984), thereby reducing

productivity. Soil surface erosion rates following timber harvest can potentially remain elevated for two

to seven years, depending upon the removal method and site characteristics. The effects of nutrient

removal through woody debris removal, soil erosion, burning and site preparation can be short lived, or

long lasting depending upon the extent, duration and intensity of the disturbance.

Past projects involved timber harvest, pre-commercial thinning, underburn, non-system road construction,

construction of log landings, and road reconstruction and road maintenance. Soil productivity has been

reduced through soil compaction, puddling, displacement, erosion, mass wasting or severe burning caused

by management actions during the implementation of these projects. Detrimental soil conditions from

these activities (Table 5) will continue to recover over time. Soil compaction will slowly decrease in the

top 4 inches of soil due to frost, fibrous plant roots and rodents. Compaction below 4 inches will change

very slowly over the next century as roots of shrubs and trees and deep burrowing rodents enter that layer.

Displaced soil from temporary roads, skid trails and landings will remain displaced unless equipment is

used to replace it. Accelerated erosion will rapidly decrease, but will only approach pre-project levels as

ground cover reaches pre-project levels, which will take a few years to decades.

Fuelwood Cutting

Cutting and removal of standing and down fuelwood or course woody material (CWM) in the project area

has reduced recycling of nutrients to the soil (within a few hundred feet of open roads) and caused

detrimental soil compaction where vehicles were driven off-road to retrieve fuelwood. The potential for

causing detrimental compaction depends on vehicular access, soil conditions at time of fuelwood

retrieval, and frequency of entry.

For these sites, shallow-rooted vegetation and rodents will slowly reduce detrimental compaction to a

depth of about 4 inches over the next few decades. Deeper compaction and detrimental displacement are

reversible only with mechanical treatment. Detrimental soil conditions (DSCs) from fuelwood cutting are

very minor, less than 0.01% across the project area, and no increase in extent is expected.

Livestock Grazing

Table 6. Livestock grazing allotments and acreages within Sparta project area

Allotment Name National Forest Acres Acres within Project Area

Eagle Valley 32,569 10,130

Goose Creek 27,269 7,227

Trouble Gulch 1,111 593

Total Acres 17,951

Livestock can cause detrimental compaction on major trails, and around watering areas and some salting

sites. Accelerated erosion also can occur at these high-use sites. The affected area overlaps most of the

entire project area, which is divided into 3 allotments (Table 6). Activities include use and maintenance

of water developments and the use of established trails by livestock. Annual grazing in the allotments has


23

led to cumulative effects in the form of detrimental soil compaction and displacement at high use sites.

The area affected by livestock with detrimental soil conditions is very small, likely much less than 0.1%

of the analysis area and no increase in extent is expected.

Noxious Weed Treatments

This activity causes negligible soil disturbance and no detrimental soil conditions. Effects of noxious

weed treatment activities on soil resources are negligible when they are applied at times and locations that

minimize risk and according to label.

Recreation Activities

Off road vehicle (ATVs) use at campsites and picnic areas causes’ detrimental soil compaction,

detrimental puddling and can lead to soil erosion. Hiking on developed trails maintains bare soil

conditions and accelerates erosion on those trails. The affected area (excluding road use which is

discussed above) is much less than 1% of the project analysis area. No change is expected in detrimental

soil conditions due to repeated annual use of dispersed recreation sites and facilities.

Wildfire

Erosion rates after a major wildfire would increase 100 times or more, from about 0.05 ton/acre/year to

more than 5 tons/acre/year for moderate to high severity (DeBano et al 1998) wildfire in a burned area

large enough to allow overland flow to reach a stream. Effects would be similar to those documented on

the forest for the Monument Fire (Bliss 2003b).

Severe burn effects followed by infrequent short-duration, high-intensity (10 to 100-year 30-minute)

storms and more common long-duration (2 to 5-year 6 to 24-hour) storms would likely cause severe

erosion and sedimentation on steeper slopes before adequate ground cover canopy cover would be

achieved. Based on ground cover recovery studies in the Blue Mountains (Johnson 1998), under natural

conditions with no livestock grazing it is estimated it would take about 1 year to achieve minimum

desired ground cover in low severity burn areas, about 2-3 years in moderately low severity burn areas,

and about 3-5 years in moderately high and high severity burn areas. It would take decades to achieve

optimal desired condition of 85-100% ground cover under a forest canopy.

Were wildfire to occur in or above any unstable or marginally stable area, there is a high probability that

movement in existing unstable areas would accelerate, and that new landslides would develop in

marginally stable areas. Total acreage of a debris avalanche, or slump/earthflow could exceed 10 acres in

some areas, such as along Eagle Creek or Little Eagle Creek. Moderate to high severity wildfire in or

above any unstable or marginally stable area would accelerate landslide movement. Movement may be

slow (slump or soil creep) to fast (debris flow or avalanche). Slumps and soil creep or earthflows may be

short to long-duration events. Movement may occur once over a period of seconds to minutes, or may

occur over longer periods. Debris flows or avalanches are rapid events; elapsed time would be seconds to

minutes (Varnes 1978).

Detrimental Soil Conditions (DSCs)

Previous entries for timber harvest, slash disposal and road building were the major causes of direct

effects leading to DSCs for project area soils. Firewood cutting, recreation uses including ATV use on

trails or cross country and livestock grazing generally have caused lesser amounts of DSCs within the

proposed treatment units. DSC values described here are the result primarily of direct effects to soils

from compaction or displacement by various management activities. The direct effects from management

can lead to indirect effects such as soil erosion. Direct effects on forest soils gradually recover over time.

DSC surveys essentially measure residual effects of past and on-going management on the soil resource.


24

Alternatives 2 and 3

Alternatives 2 and 3 would remove biomass with tractor/ground-based logging on 3,846 and 3,459 acres,

respectively. Skyline cable system logging would occur on 570 and 323 acres respectively. Vegetation

would be removed by logging systems on a total of 4,416 acres for Alternative 2 and 3,782 acres for

Alternative 3. Other effects analyzed include fuels treatments, and soils effects from system and

temporary roads. The focus for this analysis of effects of the project is the condition of soils within

project units. It is estimated that detrimental soil disturbance would occupy approximately 8% to just

under 20% of the project acres for most units after project implementation.

Alternative 2 and Alternative 3 were analyzed for this project to determine the magnitude of effects on the

soil resource. Alternative 2 has the greatest potential effect on soils, so this analysis will focus on

Alternative 2 effects. Table 9 lists all proposed project activities. Table 10 shows tractor logging and

skyline logging areas by project alternative and land type association. Project effects are predicted based

on soil effects models discussed in later sections of this report, rather than LTAs.

Table 9. Action Alternatives management activities for Sparta Project.

Management Activities Alternative 2 Alternative 3

Forested Stand Treatments Acres Acres

Commercial Thinning (HTH) 4,196 3,600

Partial Overstory Removal (HOR) 217 181

Aspen Restoration/Conifer Removal 14 13

Total Commercial Harvest Acres 4,427 3,794

Pre-commercial thinning (PCT) post-harvest 3,997 3,401

Pre-commercial thinning (PCT) only 1,362 1,510

Total PCT Acres 5,359 4,911

Fuels Treatments Acres Acres

Post-Activity Prescribed Fire (RXF) Treatments

5,527 4,876

Natural Fuels Prescribed Fire (RXF) 4,793 4,543

Total RXF Acres 10,320 9,419

Logging System Activities Acres Acres

Tractor 2,715 2,324

Forwarder 1,129 1,134

Skyline 569 323

Total Logging System Acres 4,413 3,781

Transportation Activities Miles/Units Miles/Units

Maintain NF System Roads for log haul 128.5 122.5

Open Roads (ML2-3) 80.7 79.9

Closed Roads (ML1) 47.8 42.6

Total Temporary Road Miles 2.9 0.34

New Construction 2.56 0

Existing Wheel tracks 0.34 0.34

Decommissioning System Roads 6.9 6.9

Reconstruction of System Roads 26.6 25.7

Bridge Replacement/Reconstruction 1 Bridge 1 Bridge

Bridge Abutment Repair 2 Bridges 2 Bridges

Table 10. Proposed Action logging systems and treatment areas by land type association (LTA)

Logging System Alternative 2 Logging System Alternative 3

Map Unit

Tractor Forwarder Skyline Total

Map Unit


Acres

116 715 100 108 923 116 570 108 80 759

117 62 18 107 187 117 33 0 70 103


25

Logging System Alternative 2 Logging System Alternative 3

Map Unit


Map Unit


Acres

131 24 0 21 45 131 0 0 13 13

166 15 0 0 15 166 <1 0 0 <1

167 49 1 128 178 167 41 3 78 122

168 2 0 28 30 168 0 0 0 0

216 898 7 94 999 216 755 7 57 819

217 13 0 0 13 217 1 0 0 1

256 <1 0 0 <1 256 <1 0 0 <1

266 819 1,003 15 1,837 266 815 1,016 0 1,831

267 101 0 37 138 267 101 0 24 125

268 2 0 0 2 268 2 0 0 2

317 14 0 31 45 317 4 0 <1 4

Totals 2,715 1,129 569 4,413 Totals 2,324 1,129 323 3,781

Detrimental Soil Conditions

Detrimental soil condition are caused by any management practice that results in loss of productivity due

to soil compaction, puddling, displacement, erosion, mass wasting or severe burning.

DSCs ranged from 3-19% on project units after treatment and mitigations.

Table 11. Alternative 2 DSCs in select treatment units based on soils models surveys

Unit

Ground-based acres


Existing DSC's

(%)

Post-Harvest DSC's

Unit

Ground-based acres


Existing DSC's (%)

Post-Harvest DSC's

4 24 (GP) 4 17 81 144 4 5

7 7 4 17 89 27 (GP) 5 18

12 106 (GP) 5 18 90 13 (S) 4 4

13 10 3 16 91 32 (GP) 5 18

14 85 3 16 107 15 5 18

18 24 3 16 118 39 (GP) 4 17

32 119 (F) (GP) 4 17 119 8 (S) 4 5

34 78 (F) (GP) 4 17 125 41 (GP) 3 16

35 46 (F) (GP) 4 17 129 55 (GP) 4 17

36 125 (F) 4 17 131 54 (F) (GP) 4 17

38 122 4 17 134 43 (F) (GP) 5 18

40 14 (F) (GP) 4 17 139 10 (S) 6 7

41 139 (F) 2 15 152 8 (GP) 6 19

43 200 (F) 2 15 618 311 (RXF) 4 17

45 90 (GP) 3 16 620 117 (RXF) 3 16

46 176 (F) 2 15 630 367 (RXF) 4 17

48 34 (GP) 4 17 F = Forwarder yarding GP = Grapple Piling

RXF = Prescribed burning S = Skyline yarding

50 31 3 16

52 89 (GP/RXF) 3 5

53 108 3 16

61 6 (RXF) 4 17


26

Unit

Ground-based acres


Existing DSC's

(%)

Post-Harvest DSC's

Unit

Ground-based acres


Existing DSC's (%)

Post-Harvest DSC's

62 97 (RXF) 4 17

73 252 (RXF) 2 15

74 137 (RXF) 2 15

Effects for the proposed action (Alternative 2) would have the greatest effect on soils of all the

alternatives. Effects described here are for both action alternatives, based on the effects of

implementation of the Alternative 2. Effects to soils would be slightly less for Alternative 3 because of

reduced harvest treatment acres for this alternative.

For comparisons between alternatives estimated total detrimental soil conditions for both action

alternatives were calculated based on the anticipated type of treatment. These estimates are for post-

project detrimentally disturbed soil as a result of implementing the project only, and do not account for

existing detrimentally disturbed soil areas. Detrimental soil conditions are estimates based on soils

effects models. Results of the models for the project estimate acres of detrimentally disturbed soil, and

are shown in Table 12.

Table 12. Total detrimental soil condition acres estimated from Sparta project by action alternative.

Treatment Detrimental Soil Conditions (acres)

Alternative 2 Alternative 3

Ground-Based Logging 353 302

Forwarder Logging 147 147

Skyline Logging 57 32

Prescribed Burn 0 0

Totals 557 481

Alternative 2 creates an estimated additional 500 acres of detrimentally disturbed soil based on soil

effects models for ground-based logging, and 57 acres for skyline logging, with total detrimentally

disturbed soils of 557 acres. Alternative 3 will create 449 acres of ground-based and 32 acres of skyline

detrimentally disturbed soil with total detrimentally disturbed soils of 481 acres.

The effects to soils from implementation of all action alternatives would be similar in terms of total

DSCs. Acres of DSCs for Alternative 3 soil effects would be less than Alternative 2. The difference

between Alternative 2 and Alternatives 3 and 4 is less than 100 acres of DSCs. Implementation of

Alternative 2 will lead to more soil effects than alternative 3. Alternative 3 would create about 76 acres

or 14% less DSCs than Alternative 2. For ground-based logging, Alternative 3 would create 51 acres less

DSCs than Alternative 2. Reducing ground based logging would have the greatest effect on reducing

DSCs for comparison of alternatives.

These results provide background information on how Alternative 2 compares to other alternatives

regarding detrimental soil conditions. The difference in alternatives shows that there would be less

detrimentally disturbed soil in Alternative 3. Effects to soils for this analysis in the following discussion

are discussed in term of erosion and mass wasting risk, and soil quality. The following discussion

highlights specific effects of the implementation of the action alternatives.

Vegetation Removal Effects

Commercial harvest treatments in both alternatives would remove a considerable amount of forest

overstory and understory vegetation depending on the prescription for the stand. Commercial harvest

would take place on 4,427 and 3,794 acres respectively for Alternatives 2 and 3 (Table 9). Non-

commercial thinning would remove mostly understory trees, and would take place on 1,362 and 1,510


27

acres for Alternatives 2 and 3. Prescribed burns and other fuels treatments would primarily target

understory vegetation. Fuels treatments would take place on 4,793 and 4,543 acres for Alternatives 2 and

3. Removal of vegetation would reduce the amount of material available for erosion control and nutrient

recycling. Overall, removal of vegetation would have effects, but not adversely affect short and long-

term soil productivity as effects tend to be localized.

Erosion: Any increase in erosion as a result of removing vegetation would be indirect. Harvest of trees

would reduce canopy cover by about 10-30%, which would reduce interception loss by the forest canopy

by a small percentage. It would also increase rainfall delivery to the ground, again by a small percentage.

This could lead to increased localized erosion in bare compacted soil areas during intense rainfall events,

and would increase potential for localized erosive overland flow following ground-disturbing activities

(yarding, grapple-piling of slash, pile burning and underburning) until ground cover potential is increased

by litterfall and re-growth of vegetation. The effects of increased erosion potential would slowly return to

pre-harvest levels as tree canopies expand over 20-30 years to fill space vacated by harvested trees. For

this project erosion is not expected to increase significantly as result of vegetation removal based on

WEPP model runs. See the Sparta hydrology report for modeling results. Risk of delivery of sediment to

streams from operation in project units is very low.

Mass Wasting: All effects would be indirect. Root systems of trees reduce soil creep on steeper slopes,

usually steeper than 60%. Root systems of trees also reduce landslide potential especially in areas where

the seasonal or permanent ground water table is at or near the soil surface, such as in RHCAs. Current

stability of harvest units and adjacent areas is relatively stable. Harvest of trees in steeper areas outside of

RHCAs would slightly increase potential for soil creep and landslides in those areas.

Mass wasting potential on steep slopes would increase for 5-20 years as roots of stumps rot, then would

stabilize and drop as roots of existing trees grow into those areas and as new trees establish deep root

systems. Mass wasting potential in areas with high ground water table (in RHCAs) would slowly

decrease as trees in upslope harvest units grow.

Soil Quality: Soil quality effects would be direct and indirect. Felling of trees would cause some soil

compaction and displacement, but the effects would be non-detrimental. Harvest of trees would reduce

annual production of fine organic matter (needles, twigs, limbs) necessary for erosion control and nutrient

recycling in forests.

All coarse woody material (CWM) from trees would not be removed during harvest operations. Residual

CWM from harvest operations would include stumps, tops, limbs, defect, breakage, trees felled during

temporary road construction, and trees felled for access or safety purposes during yarding. In skyline

yarding units, tops would be removed to landings. In all units, most harvest-generated slash left in units

would be piled and burned. Therefore, most residual CWM from harvest operations would be in large

logs left for wildlife purposes and in stumps. CWM left in stumps would likely be in the 0.5-1.5 tons/acre

range (Bliss 2004d). CWM left in logs for wildlife purposes would also most likely be in the 0.5-1.5

tons/acre range (Bliss 2004d). Therefore, total residual CWM would likely be in the 1.0-3.0 tons/acre

range. This analysis does not account for CWM piled and burned, and burned during underburning, nor

does it account for in-fall of green and dead trees.

CWM provides many long-term benefits for soils and the environment. It is a food source for many

organisms that recycle wood into the soil, including plants, fungi, ants, and soil animals. It is a slow-

release source of nitrogen and other nutrients. It is one of the ground cover components important for

erosion control. It is a source of complex carbon compounds essential for maintenance of soil structure.

It provides habitat for small rodents that churn the soil surface, thereby incorporating woody debris and

other organic materials into the soil. Removal of timber from the units would reduce the above long-term

benefits of CWM.


28

Status of CWM tonnage in harvest units over the next 20-30 years to the next harvest cycle is uncertain.

Few trees are expected to die and fall to the ground in this time period. Inputs from snag falls, lightning

strikes, wind microbursts and prescribed fire tree mortality would add perhaps 1 ton/acre of CWM in

affected sites. Prescribed fire at intervals would reduce CWM by burning rotten stumps and rotten logs.

Therefore, it is likely that, on a landscape basis, CWM tonnage in units would go down over the next 20-

30 years due to frequent prescribed fire.

Ground-based Yarding Systems

Ground-based yarding is proposed on 3,844 acres (tractor and forwarder) for Alternative 2, with slightly

less acres and overall effects to soils for the Alternative 3 (3,458 acres). Consequently, DSCs generated

by Alternative 3 would be slightly less for ground-based logging. Ground-based yarding is done on

slopes up to about 30% slope gradient; there are inclusions of steeper slope areas in some units. Landings

would be spaced about 500 to 800 feet apart, would range from about 0.06 acre (50 ft x 50 ft) to 0.23 acre

(100 ft x100 ft) in size, and may include portions of system roads. Each landing would service an area

from a few acres to about 15 acres in size. Landings would occupy about 1-2% of each unit. Landings

are assumed to be 100% detrimental compaction and displacement.

Erosion: All effects of ground-based yarding on erosion potential would be indirect. Natural ground

cover in forested areas is 85-100%. Reduction of ground cover to less than 60% on skid trails and

landings would increase risk of accelerated sheet, rill and gully erosion during intense rainfall events,

especially in compacted bare soil areas longer than 30 feet (Hauter & Harkenrider 1988). Potential for

this to occur would increase as slope gradient and skid trail length increase and as canopy and ground

cover decrease.

The potential affected area is the 10-20% of a unit that would be in new skid trails and landings, and

reused skid trails and landings from previous entries. Implementation of standard mitigations (waterbars,

etc) would reduce potential for accelerated erosion. The objective of these mitigations is to disrupt water

erosion processes until ground cover objectives can be achieved.

Some risk for erosion of skid trails exists as analyzed using the WEPP (1999) erosion model. Erosion

predicted was for 5 and 10 year storm events, with the maximum amount predicted for a 10-year event of

0.06 tons/acre. No erosion was predicted for storm events with less than a 5 year return interval. A similar

erosion scenario is likely for landings where disturbance is greater, but slopes are generally flat on project

landings, leading to less erosion potential. For this project erosion is not expected to increase

significantly as result of ground-based yarding based on WEPP model runs. See the Sparta hydrology

report for modeling results. Risk of delivery of sediment to streams from operation in project units is

very low.

Erosion potential would drop as ground cover (litter, basal area of vegetation, biological soil crusts)

increase following logging, and would achieve minimal acceptable levels of 60-70% in about 2-5 years in

most areas. Erosion potential would also decrease as canopy cover (trees, shrubs, grasses) increases over

the disturbed areas.

Mass Wasting: All effects of ground-based yarding on mass wasting potential would be indirect. Risk

of increasing mass wasting potential is low because sensitive areas were excluded from units during unit

design.

Soil Quality: Direct effects of ground-based yarding on soil quality would include soil compaction,

puddling, displacement, and organic matter loss. Indirect effects could include increased erosion and

mass wasting potential. Soil disturbance on skid trails and landings would range from minimal

displacement of duff and vegetation to gouging and displacement and/or compaction of the soil up to

several inches deep. New ground-based yarding activities (including landings) would cause soil


29

disturbance within each unit, primarily compaction and displacement. Use of existing skid trails would

reduce potential for creating new DSCs, and would reduce final DSCs.

Over time, shallower soil compaction in subsoiled and unsubsoiled areas would naturally recover by frost

heave, rodents, and fibrous roots of plants to a depth of 4 inches over a period of 10-30 years. Deeper

(greater than 4-6 inches) compaction would persist for more than 100 years. Displacement would remain

unmitigated. Erosion potential would be higher on un-subsoiled skid trails and landings.

Skyline Yarding System

569 acres of skyline yarding would occur in Alternative 2, and 323 acres under Alternative 3. Skyline

yarding is done on slopes steeper than 30-35% slope gradient; and there are inclusions of less steep areas

in some units. Roadways and road fills would be used as is for landings. Landings would be spaced

about 200 feet apart. About 40-50 feet of road and road fill would be used for each landing. Skyline

corridors below landings would average about 12 feet wide and may be several hundred feet long. From

past harvest, it is estimated about 8 percent of units would be in skyline corridors (Bliss 2003a).

Trees would be directional-felled toward skyline corridors, then cut into lengths, and whole-tree yarded.

The trees closest to the landing would be yarded first. Trees would be single-suspension yarded, which

means the smallest diameter end of the log, including the piece with the top attached, would be dragged

on the ground. Overall, the risk of adverse effects from skyline yarding would drop quickly after the first

few years.

Erosion: All effects of skyline yarding on erosion potential would be indirect. Natural ground cover in

forested areas is 85-100%. Reduction of ground cover to less than 60% in skyline corridors would

increase risk of accelerated sheet, rill and gully erosion during intense rainfall events, especially in bare

soil areas longer than 30 feet (Hauter & Harkenrider 1988). Potential for this to occur would be highest

on the 1% of skyline corridors where DSCs may occur by logs dragging over the soil surface.

Implementation of standard mitigations for skyline corridors (i.e. waterbars if bare soil areas exceed 30

feet in length) would reduce potential for erosion. The objective of this mitigation is to disrupt water

erosion processes until higher amounts of ground cover can be achieved. Risk for erosion for skyline

yarding is less than for ground-based logging.

Mass Wasting: All effects of skyline yarding on mass wasting potential would be indirect. Risk of

increasing mass wasting potential is low because sensitive areas would be excluded from units during unit

design.

Soil Quality: Direct effects of skyline yarding on soil quality would include soil compaction and

displacement; indirect effects would include erosion. Soil disturbance in skyline corridors would range

from minimal displacement of duff and vegetation to gouging and displacement of the soil up to several

inches deep. Site conditions that would affect soil effects would include slope configuration (concave

versus convex), log weight, and quality of ground cover (coarse woody debris, sedge-grass cover). The

upper half of all corridors normally would receive the most severe soil damage; the exception is where the

slope is concave. Evidence of soil displacement in skyline corridors would persist for decades until

rodents, windthrow, soil creep and vegetation alter the soil surface. Bare soil areas in skyline corridors

would naturally develop minimal acceptable ground cover (i.e. 60-75%) in 1-5 years as litter falls from

trees and/or as plants re-colonize the sites.

Non-commercial Thinning

3,997 acres of post-harvest non-commercial thinning and 1,362 acres of non-commercial thinning only

would occur in Alternative 2. Slightly less than this amount (3,401 and 1,510 acres) would occur under

Alternative 3. For these treatments, usually trees smaller than 2-inch dbh would normally be lopped and

left on the ground. Trees larger than 2-inch dbh would be considered for machine and hand piling and


30

pile burning. Thinning and machine piling may be done at the same time with the same piece of

equipment on slopes less than 30% gradient.

Erosion: All effects of thinning on erosion potential would be indirect. Additions of woody debris

would have no effect on erosion potential, unless ground cover is below natural potential.

Mass Wasting: All effects of thinning on mass wasting potential would be indirect. No effects are

anticipated.

Soil Quality: Direct effects of thinning include adding fine organic matter and coarse woody material to

the soil surface, and increasing ground cover. Indirect effects include adding nutrients to the soil as

organic matter decomposes. Less than 5 tons/acre of standing coarse woody material from live trees

would be felled, lopped, and then hand-piled and burned as described below. Effects of machine thinning

on slopes less than 30% gradient would be as described under Grapple Pile Slash below. The coarse

woody material would slowly decay to humus over a few to several decades. Residual fine organic matter

would decay to humus in a few years to a few decades.

Grapple Pile Slash and Burning Piles in Ground-based Units

Slash in 1,668 ground-based acres in harvest units would be grapple piled following harvest and before

underburning for the proposed action. Areas in units where grapple piling take place would be slightly

less for Alternative 3 (1,540 acres), consequently effects to soils would be slightly less. All of the grapple

piles would be burned. Most of the burn effects at these sites would be high fire severity, also referred to

as severe burns (USFS 1998). There would be some moderate and low fire severity around the edges of

the piles. Severe burns in areas over 100 square feet qualify as DSCs. Most pile burns would be between

100 and 1000 square feet, so they would qualify as DSCs when burned.

Erosion: Effects would be less intense and smaller in area than those described above for ground-based

yarding Systems.

Soil Quality: The Grapple Piling Effects Model indicates there would be about 5-8% ground disturbance,

including about 1-2% DSCs. Burning of grapple piles creates 12-% DSCs. Actual DSCs would be

affected by variables such as soil texture, soil moisture, ground cover (vegetation type and woody debris

tonnage), type of equipment used, and operator skill. Reduction of ground cover to nearly bare ground in

burn pile areas would increase risk of accelerated sheet, rill and gully erosion during intense rainfall

events, especially in bare soil areas with continuous areas longer than 30 feet (Hauter & Harkenrider

1988). Potential for this to occur are low in burn pile areas because they usually will expose less than 30

linear feet of soil. Grapple piles would be between 100 and 1000 square feet in area, so they would

qualify as DSCs when burned. Total combined DSCs from grapple piling and burning piles is 2-4%.

Effects of pile burning on soil quality would be direct and indirect. Direct effects would include

consumption of fine organic matter and coarse woody material on and in the soil, mortality of plants and

animals on and in the soil surface under and near the pile, change in nutrient availability, and change in

soil structure and infiltration rate. Burning would volatilize some nutrients, and would make other

nutrients available for plant growth. Indirect effects would include increased local erosion rates. Severe

burn effects to soils under burn piles would slowly recover over a period of about 10-20 years.

Burn Machine and Hand-piled Slash at Landings

Slash piles at landings of skyline and ground-based units and hand and grapple piles would be burned.

Most of the burn effects at these sites would be high fire severity, also referred to as severe burns (USFS

1998). There would be some moderate and low fire severity around the edges of the piles. Severe burns

in areas over 100 square feet qualify as DSCs. Most of the hand piles would be smaller than 100 square

feet, so most would not qualify as DSCs. However, larger hand piles and all of the slash piles at landings


31

would be between 100 and 1000 square feet, so they would qualify as DSCs when burned. However,

burning slash piles at existing landings would not create additional DSCs.

Erosion and Mass Wasting: Burning of piles would have a negligible effect on erosion potential and

mass wasting potential.

Soil Quality: Burning of slash piles at landings of ground-based and skyline units would produce up to

0.5-1% DSCs. The estimated mean burn effect would be 1.5-3% DSCs in ground-based units and 0.5-2%

DSCs in skyline units. Effects of pile burning on soil quality would be direct and indirect and are similar

to burn effects described in grapple pile burning. Severe burn effects under burn piles would self-mitigate

over a period of about 10-20 years.

Hand or Machine Pile Slash in Non-Commercial Units

A total of up to 663 acres of slash in non-commercial units would be hand or machine piled to reduce fuel

loading before underburning for Alternative 2 and 780 acres in Alternative 3. Machine and hand piles

would be about 6 to 15 feet in diameter and could cover about 3-5% of the ground surface in each unit.

Machine piles would be larger than hand piles.

Erosion and Mass Wasting: Hand piling of slash would have no measurable effect. Machine piling will

have similar effects to grapple piling and burning of slash piles discussed in an earlier section of this

report. Machine piling will likely occur on a small percentage of treatment acres.

Soil Quality: Effects of pile burning on soil quality would be direct and indirect and are similar to burn

effects described in grapple pile burning. Severe burn effects under burn piles would be restored slowly

over a period of about 10-20 years. Hand pile burning adds 0-1% additional DSCs, and grapple pile

burns can add 1-2% DSCs. The amount of slash produced from non-commercial thinning is usually less

than in commercial logging, so DSCs estimates from burn piles will probably be less than more intensive

treatments like grapple piling and burning.

Underburn Skyline and Ground-based Units

About 4,196 acres in harvest units would be underburned for under Alternative 2 and 3,476 acres under

Alternative 3. Effects would be similar to those described in the next section on underburn (RXF) units,

with the following exceptions: Stream channels and certain landslide-prone areas were excluded from the

harvest units, but are included in RXF units or non-commercial units.

Underburn (RXF) Units

About 4,793 acres in RXF units would be underburned mostly in forested areas for Alternative 2 and

4,543 in Alternative 3. A few acres of non-forested area will be included in RXF areas. Intensities would

be a mosaic pattern of no, low, moderate and high fire severity. High fire severity is the same as

detrimental burning. Forested landscapes would experience predominantly low-severity and moderate

severity burns. Pockets of high severity burns could occur as stumps or larger logs are consumed.

Erosion: Effects of underburning on erosion potential would be indirect. The potential for erosion from

prescribed fire is low, as modeled by WEPP (1999). A 5 to 10 year storm may result in up to 0.13

ton/acre soil loss, which is very low. Erosion potential increases as fire reduces organic ground cover.

Reducing ground cover below 50-60% on hillslopes can increase the risk of severe sheet and rill erosion

during heavy rainfall events. Adequate ground cover needed to protect hillslope soils takes about 1 to 3

years to recover after prescribed burning. However, these effects would be at the low end of the normal

range of conditions one would expect following wildfire. Potential for increased erosion and

sedimentation potential in and below moderate-severity burn areas would be higher than normal for at

least 1-3 years, until ground cover returns to pre-fire levels.


32

Mass Wasting: Effects of underburning on mass wasting potential would be indirect. There are no

known high risk (active or marginally stable) mass wasting sites in prescribed burn units. Short-term

reduction in transpiration by grass, shrubs and trees killed by prescribed fire would slightly increase mass

wasting potential in wetlands below burned areas. Mass wasting potential would be higher than normal

until evapo-transpiration and ground cover return to pre-fire levels, which would take at least 1-3 years.

Soil Quality: Effects of underburning on soil quality would be direct and indirect. Direct effects would

include low to high fire severity effects, partial to complete consumption of fine organic matter and

coarse woody material on and in the soil, mortality of plants and animals on and in the soil surface, and

change in nutrient availability. Severe burn effects (i.e., formation of orange soil) would occur around

burned-out stumps, under well-burned logs, and in other deep fuel concentration areas. However, few if

any areas would be large enough to qualify as detrimental burning. Burning would volatilize some

nutrients, and would make other nutrients available for plant growth. For example, pinegrass usually

grows much taller and blooms profusely one to two years after non-lethal fire due to higher availability of

nitrogen and other nutrients. Indirect effects would include increased erosion and mass wasting potential,

as discussed above. Detrimental soil displacement would be permanent. Detrimental soil compaction and

puddling would be naturally recover through by frost heave, rodents, and fibrous roots of plants to a depth

of 4 inches over a period of 10-30 years. Deeper compaction would persist for more than 100 years. It

would take decades for organic matter to return to natural levels on fillslopes, and decades to centuries for

cutslopes; travelways would never achieve potential.

Most burn effects would recover over a period of about 1-10 years, depending on severity. The major

exceptions would be shrub or tree canopy killed by fire, coarse woody material in and on the soil that is

consumed by fire, and high fire severity (orange soil areas).

Summary of Direct and Indirect Effects for Alternatives 2 and 3:

Proposed forest treatments include ground-based harvesting, skyline yarding, temporary road construction

and road management, grapple piling, and burning of grapple-piled logging slash, slash burning at

landings, hand-piled slash burning, and reforestation, prescribed fire underburns.

For comparisons between alternatives estimated total detrimental soil conditions for both action

alternatives were calculated based on the anticipated type of treatment. These estimates are for post-

project detrimentally disturbed soil as a result of implementing the project only, and do not account for

existing detrimentally disturbed soil areas.

Implementation of the action alternatives would increase post-harvest DSCs from 3-19% in project units.

For Alternative 3, slightly fewer DSCs acres are going to be generated overall. Mitigations will be

applied that reduce DSCs below 20% for all action alternatives. The effects to soils of implementation of

the action alternatives will be similar, with the only difference that soil effects will be slightly less for

Alternative 3.

Effects for Alternative 2 would have the greatest effect on soils. Effects to soils would be slightly less for

Alternative 3 because of reduced harvest treatment acres and direct, indirect, and cumulative soil effects.

Alternative 2 creates an estimated additional 500 acres of detrimentally disturbed soil based on soil

effects models for ground-based logging, and 57 acres for skyline logging, with total detrimentally

disturbed soils of 557 acres. Alternative 3 will create 449 acres of ground-based and 32 acres of skyline

detrimentally disturbed soil with total detrimentally disturbed soils of 481 acres.

Implementation of Alternative 2 will lead to more soil effects than alternative 3. Alternative 3 would

create about 76 acres or 14% less DSCs than Alternative 2. For ground-based logging, Alternative 3

would create 51 acres less DSCs than Alternative 2. Reducing ground based logging would have the

greatest effect on reducing DSCs for comparison of alternatives.


33

For this project erosion is not expected to increase much as result of ground-based yarding or other

activities based on WEPP model runs for the action alternatives. Soil erosion risk is slightly less for

Alternative 3. Risk of delivery of sediment to streams from operation in project units is very low. Some

risk for erosion of skid trails exists as analyzed using the WEPP (1999) erosion model for ground-based

yarding. Erosion predicted was for 5 and 10 year storm events, with the maximum amount predicted for a

10-year event of 0.06 tons/acre. No erosion was predicted for storm events with less than a 5 year return

interval. A similar erosion scenario is likely for landings where disturbance is greater.

Erosion potential would reduce as ground cover (litter, basal area of vegetation, biological soil crusts)

increases following logging, and would achieve minimal acceptable levels of 60-70% in about 2-5 years

in most areas. Erosion potential would also decrease as canopy cover (trees, shrubs, grasses) increases

over the disturbed areas.

Cumulative Effects for Soils

Introduction

Cumulative effects on soils reflect present, on-going, and reasonably foreseeable future actions which

overlap in time and space with the Sparta project and which would contribute to a measurable cumulative

effect on soils resources. The existing condition of project unit soils reflects the impacts of a wide variety

of past actions and is reflected in the affected environment section (Table 8). Detrimental soil conditions

reflect past effects to soils. Present and reasonably foreseeable future actions are summarized in

Appendix D of the Sparta EA.

Cumulative effects to soils for this project are estimated by the existing/ongoing and proposed future

extent and amounts of detrimental soil conditions. DSCs are a good estimate for soils effects, and are

used in this report to show cumulative effects to soils from the project activities and other on-going and

future activities occurring in the project units. The extent and patterns of detrimental soil conditions are

an indicator and an effective way to determine how management has affected soils up to the present.

Equipment use and soils effects models presented earlier in this document provide a mechanism for

determining specific future effects.

Alternative 1

The existing conditions within the project area would continue as they are currently exist. Only the

potential for a wildfire and the implementation of a forest-wide travel management plan would have a

measureable effect on the condition of soils resources within the project area when combined with what is

currently occurring. It is impossible to estimate the potential DSCs associated with a wildfire; however,

depending on the conditions and time of year, they could be significant.

The travel management plan would manage cross-country motor vehicle use and limit use to designated

roads, trails, and areas which would allow user built roads and trails to recover and grow back over

improving soil conditions and allowing for existing detrimental soil conditions to rehabilitate.

Alternatives 2 and 3

The following table determines if any of the present and reasonably foreseeable future activities within

the project area would overlap in time and space with the activities in the Sparta project and create a

measurable cumulative effects. These effects will be discussed in detail in this analysis.


34

Table X. Cumulative Effects Determination Table for Soils Resources

Project Potential Effects

Overlap in: Measurable Cumulative

Effect?

Effects

Time Space

Noxious Weed Management

Reduction of invasive species competition

Yes Yes No

Does not create any ground disturbance.

Veg Management No No No

Fuels Reduction & Rx Burning

No No No

Special Uses:

Brooks Ditch

Yes Yes No

Recreation – Eagle Creek Wild & Scenic River

Yes Yes No

Recreation- Dispersed Camping

Yes Yes No

Potential for some disturbance but primarily would occur within already disturbed areas.

Recreation- Snowmobile Trails

No No No

Recreation -Firewood Cutting

Yes Yes No

Some disturbance from skidding trees and driving off road to retrieve wood – but generally very limited where occurs and minor in nature.

Recreation – OHV Use

Yes Yes No

Recreation – Lilly White Guard Station

No No No

Roads & Trails – Travel Management Plan

Yes Yes Yes

Would manage cross-country motor vehicle use and limit use to designated roads, trails, and areas which would allow user built roads and trails to recover and grow back over. This in combination with the decommissioning or roads and the obliteration of temporary roads on existing wheel tracks would provide for a long term beneficial effect to soils.

Road Maintenance – 7700 & 7745 Roads

Yes Yes No

Already disturbed

Roads – Danger Tree Removal

Yes Yes No

Minor, same as firewood.

Grazing Allotments Yes Yes No

Potential additional access of cattle into units previously inaccessible.

Wildlife Enhancement – Eagle Creek Cooperative Closure Area

Yes Yes No

Mining No No No

No approved plans of operation

Private Land Activities

Private Structures

3 Year round Residences

No No No

Don’t overlap in time and space because units are all on NFS lands.


35

Recent and Ongoing Actions – estimated DSCs:

Livestock Grazing (3 allotments)- much less than 0.1% new DSCs from trails, water/salt areas, no

new DSCs since salting/watering areas and trails are established.

Fuelwood Cutting (annually)- Virtually un-measureable increases in DSCs from this activity,

very small amount of new impacts expected.

Noxious Weed Treatments along open roads (annually)- 0% DSCs

Recreation: camping, ATV use, snowmobile use, use of trails to wilderness- DSCs amount very

small, nearly un-measureable, may be locally significant, no new DSCs expected.

The upcoming forest-wide travel management plan would manage cross-country motor vehicle use

limiting motor vehicle use to designated roads, trails, and areas which would allow user built roads and

trails to recover and grow back overtime. This in combination with the decommissioning of roads and the

obliteration of temporary roads on existing wheel tracks would provide for a long term beneficial effect to

soils further reducing DSCs within the project area. Thus, the cumulative effects to soils from those

predicted DSCs from this project and on-going and reasonably foreseeable future activities are not likely

to exceed 20% in individual units as a result of the project.

Consistency with Laws and Policy

All action alternatives would meet soil Forest Plan and Regional soil standards designed to maintain long-

term soil productivity.

Monitoring

BMPs and other methods for erosion control such as water bars, limiting operating seasons, designated

skid trails, or the use of existing landings and designated skid trails, etc. are effective measures for

minimizing or rehabilitating potential soil impacts. The analysis of effects included implementation of

these mitigations to help reduce soil erosion and other effects, and help maintain DSC levels within Forest

Plan standards for all action alternatives. Effectiveness monitoring of BMPs will take place during and

after project activities for a percentage of units. BMP implementation monitoring which is evaluation of

whether BMPs are used during the project is also going to take place. This monitoring will be carried out

by the timber sale administrator, or by the district hydrologist or soil scientist.

BMP monitoring will take place following treatment (veg and fuels work). If units are found that exceed

Forest Plan and Regional soil standards for DSC’s, mitigation work will be necessary to meet these

standards to maintain soil productivity.

Special emphasis for monitoring is recommended for the following units: Units 4, 54, 66, 67, and 81 all

have high sediment delivery potential and are either tractor and/or machine pile units. Units 32, 48, 87,

91, 92, 96, 104, 115, 117, 118, 113, 140 and 152 all have high risk for soil erosion when disturbed and are

either tractor and/or machine pile units. These units listed should receive special attention during

treatment to reduce the potential for surface erosion and sediment delivery. It is recommended that

additional BMP effectiveness monitoring take place during project implementation in these units, with a

special emphasis on proper water bar construction and spacing.


36

References

Belnap, J., R. Rosentreter, S. Leonard, J.H. Kaltenecker, J. Williams, and D. Eldridge. 2001. Biological

Soil crusts: Ecology and Management. USDI Bureau of Land Management National Science and

Technology Center, Denver CO. Tech Ref 1730-2 http://www.blm.gov/nstc/library/pdf/CrustManual.pdf.

Benson, R.E. 1982. Management consequences of alternative harvesting and residue treatment practices –

lodgepole pine. USDA Forest Service, Gen. Tech. Rpt. INT-GTR-132.

Bliss, T. M. 2001a. Summary of Soil-Related Standards and Guidelines in the Wallowa-Whitman

National Forest Land and Resource Management Plan. (Draft #2)

Bliss, T. M. 2001b. Existing Condition and Effects Report, Boulder Beetle Project Analysis, Pine Ranger

District. December 13, 2001.

Bliss, T. M. 2003a. Observations of burn effects and logging effects in the Dark Meadow, McMeadow,

Barnard and Monument project areas, 2000-2003, as reported in McMeadow EA and Monument EIS.

Bliss, T.M. 2003b. Soils Existing Condition Report, Monument Fire Recovery Area, Unity District.

Wallowa-Whitman NF, Baker City, OR. February 19, 2003.

Bliss, T. M. 2004. Soil Quality Monitoring in Sumpter Interface Timber Sale Skyline Units. May 11,

2004. Whitman Unit.

Bliss, Timothy M., 2009. Boulder Creek Watershed Condition Assessment

Buckman, H. O. & N. C. Brady. 1969. The Nature and Properties of Soils. 7th ed. The Macmillan

Company, New York, New York. Factors influencing soil formation; pp. 297-298.

Curran, Mike, Pat Green and Doug Maynard. 2007. Volcanic Ash Soils: Sustainable Soil Management

Practices, With Examples of Harvest Effects and Root Disease Trends. USDA Forest Service Proceedings

RMRS.

DeBano, L. F., Neary, D. G., and Ffolliott, P. F. 1998. Fire’s Effects on Ecosystems. John Wiley &

Sons, New York, N. Y. pp. 62-63.

Federal Water Pollution Control Act (Clean Water Act) as amended [PL 103-303]. November 27, 2002.

(33 U.S.C. 1251 et seq.).

Fouty, S. 2004. Watershed Analysis of Potential Effects of the Proposed Barnard Vegetation

Management Project

Froehlich, H.A. and D.H. McNabb. 1984. Minimizing soil compaction in Pacific Northwest forests In:

Forest soils and treatment Impacts Proc6th N. Amer. For. Soils Conf E.L Stone (Ed ) Dept Forestry,

Wildlife and Fisheries, Univ. Tennessee, Knoxville, Tenn. pp. 159-1 92

Froehlich, Henry A. 1984. Mechanical Amelioration of Adverse Physical Soil Conditions in Forestry.

Symposium on Site and Productivity of Fast Growing Plantations, in Proceedings Pretoria and

Pietermarizburg, South Africa May 1984, International Union of Forestry Research Organizations. 1984;

1:507-521.

Graham R.T. et al 1994. Managing Coarse woody Debris in Forests of the Rocky Mountains. USFS

Research paper INT-RP-467, Intermountain Research Station, 12 p.

Hansen, Barry. As cited in Pine Valley Project Record, Fuel Management Specialist on ID Team, Pine

Valley Project, 2005.


37

Harvey et al. 1987. Harvey, A. E.; Jurgensen, M. F.; Larsen, M. J.; Graham, R. T. 1987. Decaying

organic materials and soil quality in the Inland Northwest: a management opportunity. Gen. Tech. Rep.

INT-225. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station.

15 p.

Hauter, K. & D. Harkenrider. 1988. Watershed Management Practices: Guide for Achieving Soil and

Water Objectives. Wallowa-Whitman N. F. Baker City, OR. Prescribed and natural fire standards and

guidelines; pp. 56-58. Waterbars, pg. 33.

Howes, S. 2004. Minimum Requirements for Soils information in NEPA documents. Personal

communication 2007.

Howes, S. 2001. Interim Protocol for Assessment and Management of Soil Quality Conditions. Version

3.3, September 2001. Wallowa-Whitman NF.

Johnson, Charles Grier. 2003. Green Fescue Rangelands: Changes Over Time in the Wallowa

Mountains. PNW-GTR-569. USDA Forest Service, Pacific Northwest Research Station, Portland,

Oregon.

Johnson, C. G. Jr. 1998. Vegetation Response after Wildfires in National Forests of Northeastern

Oregon. USDA Forest Service, Pacific Northwest Region. R6-NR-ECOL-TP-06-98

Kreger, Art. 2004 Personal communication, as cited in Pine Valley Project Effects Report, Wallowa-

Whitman NF, 2005). Observations of grapple piling effects in Deer units, Whitman Unit.

Leonard R. Johnson, Debbie Page-Dumroese and Han-Sup Han. 2007. Effects of Machine Traffic on the

Physical Properties of Ash-Cap Soils. USDA Forest Service Proceedings RMRS-P-69-80.

Lynch, J.A., AND E.S. Corbett. 1990. Evaluation of best management practices for controlling nonpoint

pollution from silvicultural operations. Water Resource. Bull. 26:41–52.

McNeil, R. 1996. Effects of a Feller-Buncher Operation on Soil Bulk Density. Blue Mountain Ranger

District, Malheur National Forest. John Day, OR.

Page-Dumroese, D.S.; Jurgensen, M.F.; Tiarks, A.E.; Ponder, F., Jr.; Sanchez, F.G.; Fleming, R.L.;

Kranabetter, J.M.; Powers, R.F.; Stone, D.M.; Elioff, J.D.; Scott, D.A. 2006. Soil physical property

changes at the North American Long-Term Soil Productivity study sites: 1 and 5 years after compaction.

Can. J. For. Res. 36: 551–564.

Risch, A.C., M.F. Jurgensen, and D.A. Frank. 2007. Effects of grazing and soil micro-climate on

decomposition rates in a spatio-temporally heterogeneous grassland. Plant Soil 298:191-201.

Stuart, G.W. and P.J. Edwards. 2006. “Concepts about forests and water.” Northern Journal of Applied

Forestry 23:1, 11-19.

USFS. 1978. U. S. Forest Service Handbook 2509.13. Section 25.12 Estimating Acceptable Soil Cover.

USFS. 1984. U. S. Forest Service Handbook 2209.21 R6-Supplement-5/84. Section 244.2.c. Ground

Cover.

U.S.D.A. Forest Service Wallowa-Whitman N.F Land and Resource Management Plan (Forest Plan).

1990.

U.S.D.A. Forest Service Forest Service Manual 2500 Chapter 2550 Soil Management (1990).

USDA Forest Service. 1990. Wallowa-Whitman National Forest Land and Resource Management Plan.

USFS. 1998. FSM 2521 R6-Supplement-2500-98-1. Watershed Protection and Management.

USFS. 2000. FSM WO Amendment 2500-2000-2. Section 2521 - Watershed Condition Assessment.


38

Varnes, D. J. 1978. Slope Movement and Types and Processes. In Landslides: and Control.

Transportation Research Board, National Academy of Sciences. Washington, D. C. Special Report 176.

Chapter 2, Figure 2.1, Types of Slope Movement.

WEPP 1999. Water Erosion Prediction Project Computer Model William J. Elliot, Project Leader David

E. Hall, Computer Programmer/Analyst Dayna L. Scheele, Civil Engineer U.S.D.A. Forest Service Rocky

Mountain Research Station and San Dimas Technology and Development Center.


39

Appendix A

Interim Protocol for Assessment and Management of Soil Quality Conditions

Wallowa-Whitman National Forest Version 3.3 September 2001

The objectives of this protocol are to: 1) Establish consistency in soil assessment methods on the

Wallowa-Whitman National Forest and 2) Ensure compliance with the forest’s Land and Resource

Management Plan and FSM 2520.3. Testing of this interim protocol will occur during the next several

months, and revisions will be made if necessary.

This protocol describes how to assess the existing condition of soils in areas where proposed or current

management activities have the potential to affect the soil resource, with emphasis on mechanical

treatments. Summaries and interpretations of soil management direction in the Forest Land and Resource

Management Plan and FSM 2500.98-1 are also given.

ASSESSMENT

Step 1: Initial Assessment Complete an ocular assessment of the activity area during project design, focusing on past management

activities and current conditions of the soil surface. Classify the relative proportions of each unit in terms

of soil disturbance using the Level I Soil Class Disturbance Definitions (Attachment 1). Complete the

Level I Soil Survey Data Form (Attachment 2), which, summarizes the degree of soil disturbance, extent,

and distribution by activity unit. This step may be completed by a non-soil scientist.

Step 2: Potential Impact Assessment Assess the potential for soils impacts based on soil type and proposed management activities. Assess the

potential for proposed management activities to affect soil resources in all activity units. If site specific

prescriptions for activity units are not known at the time of initial assessment, use ecological unit

inventory information and information from Step 1 to evaluate the potential for impacts given a range of

management activities. This step should be completed by an interdisciplinary team, including a soil

scientist.

Step 3: Unit Prioritization Sampling of all activity units may not be necessary or possible. Prioritize units using the conceptual

model shown in Figure 1. Priority will be given to those units where soil quality standards may be in

question and/or proposed activities have the potential to exceed soil quality standards. Determine which

units to sample based on priority level. This step should be completed by an interdisciplinary team,

including a soil scientist.


40

Level of Concern Related to

Existing Conditions1 P

ote

ntia

l fo

r S

oil

Imp

acts

2

Low

Medium

High

Lo

w

Me

diu

m

Hig

h

Figure 1. Unit prioritization model.

Step 4. Unit sampling Once all the units have been prioritized, identify units to sample based on priority level and available

resources. Sample the appropriate units and categorize the soil conditions using the Level II Soil Class

Disturbance Definitions and the Level II Soil Survey Data Form. The Level II survey can be completed

by a Soil scientist or any individual with proper training. The sampling method will be determined by a

soil scientist. The following methods should be considered based on the quantity and quality of data

desired.

Statistical Point Sampling Method: See Howes, S., Hazard, J., and Geist, J. 1983. Guidelines

for Sampling Some Physical Conditions of Surface Soils. R6-RWM-146-1983, p. 5-6. Sampling

intensity should be 5 20-point transects per 10 acres, all random. This is an average of 10 data

points per acre.

Random Points: A minimum of 2 random data points per acre, with a minimum of 30 data

points per analysis area.

Transects: A minimum of 1 transect across a representative section of an analysis area.

Continuously observe surface soil conditions, recording the number of paces in each soil

disturbance class. If there are different conditions in different parts of the analysis area, a transect

should be made through each area, with an estimate of the percent of the analysis area represented

by the transect. There are usually several hundred data points per transect. This is not a

statistical sample.

1 Judgment call based on Level I Inventory.

2 Judgment call based on the potential for soil impacts.

Priority for Level II

High

Medium

Low


41

When calculating the percentage of an activity unit that contains detrimental soil conditions, use the

percentage of points designated as Class 2 or Class 3.

Definitions of Detrimental Soil Conditions Detrimental Compaction, Puddling and Displacement: The official definitions of detrimental compaction,

puddling and displacement (USFS 1998) is: Detrimental compaction is an increase in soil bulk density of

20%, or more, over the undisturbed level, for volcanic ash, and 15% for other soils, below a depth of 4

inches. Detrimental puddling is evidenced by ruts 6 inches or more deep; soil deformation and loss of

structure are observable and usually bulk density is increased. Detrimental displacement is removal of

more than 50% of the A horizon from an area larger than 100 square feet, which is at least 5 feet wide.

The practical application of these definitions in the new field protocol (HOWES 2001) was to identify

soil compression or displacement deeper than 4 inches as detrimental, regardless of width crossed by a

transect, so percent effects could be more accurately mapped.

Detrimental Burning (Severe Burning): The official definitions of detrimental burning reads: “Mineral

soil surface has been significantly changed in color, oxidized to a reddish color, and the next one-half

inch blackened from organic matter charring by heat conducted through the top layer, in an area greater

than 100 square feet, which is at least 5 feet in width” (USFS 1998). The practical application of this

definition in the new field protocol (HOWES 2001) was to map severe burn conditions regardless of

width crossed by a transect, so percent effects could be more accurately mapped.

Detrimental Erosion: The official definition of detrimental erosion reads: “For effectiveness monitoring,

detrimental erosion is visual evidence of surface soil loss in areas greater than 100 square feet, rills or

gullies, and/or water quality degradation from sediment or nutrient enrichment” (USFS 1998): This

definition mixes accelerated and detrimental erosion, and needs to be interpreted in the context of what is

truly detrimental to soil productivity. The practical application of this definition in the context of the new

field protocol (HOWES 2001) was to identify soil erosion deeper than 4 inches as detrimental; this

included deep rills (4-6 inches deep) and gullies (>6 inches deep. This interpretation parallels the

detrimental displacement definition.

Detrimental Mass Wasting: The official definition of detrimental mass wasting reads: “visual evidence of

landslides associated with land management activities and/or degrades water quality” (USFS 1998): This

definition mixes non-detrimental and detrimental types of mass wasting. For example, only small

portions of earthflows are detrimental to soil productivity. The practical application of this definition in

the context of the new field protocol (HOWES 2001) was to identify mass wasting areas where more

than 4 inches of topsoil was lost. This interpretation parallels the detrimental displacement definition.

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