Draft Supplemental EIS APPENDIX D Page D-1 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

APPENDIX D 

Watershed and Soil 

Characteristics 

HYDROLOGY 

The effect of roads and trails on hydrologic systems is usually analyzed at the site-scale and at 

the watershed scale in order to evaluate direct impacts of the road alignment (site-scale) and the 

indirect and cumulative watershed effects. Alternatives for motorized use designation have been 

analyzed at the site scale and the 6th field or “subwatershed” scale. 

Appendix D presents the 5th and 6th field watersheds that have been analyzed. These 

subwatersheds are analyzed because they represent those watersheds where actions are being 

proposed to occur that would potentially affect (either adversely or beneficially) current 

conditions. Included are watershed characteristics, risks for adverse effects, key watershed and 

water quality listing status and Riparian Reserve status. 

WATERSHED ANALYSES 

The following Watershed Analyses were examined for current conditions information and used 

in effects analysis: 

 1995 North Fork of the Smith River, Chetco RD 

 1995, Upper Rogue River Watershed, Prospect RD 

 1995, Squaw/Elliot/Lake Watershed Analysis, Applegate RD 

 1995, Silver Creek National Watershed #9, Galice RD 

 1996, Chetco River Watershed Analysis, Chetco RD 

 1996, Quosatana Creek Watershed Analysis, Gold Beach RD 

 1997, Draft Grayback/Sucker Pilot Watershed Analysis Results, Illinois Valley RD 

 1997, Lawson Creek Watershed Analysis, Gold Beach RD 

 1998, Elk River Watershed Analysis, Gold Beach RD 

 1998, Hunter Creek Watershed Analysis, Gold Beach RD 

 1998, Middle Fork Applegate River Watershed Analysis, Applegate RD 

 1999, Middle Illinois River Watershed Analysis, Illinois Valley RD 

 2000, East Fork Illinois River Watershed Analysis, Illinois Valley RD 

 2000, Rogue River below Agness Watershed Analysis, Gold Beach RD 

The following 5th and 6th field watershed were considered based on the Proposed Action and are 

the basis of effects discussion in the EIS. 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest Table D-1. TMP Proposed Action Watersheds

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Powers District

Big Tree Trail

#1150

4

& 5

Trail‐

prohibit

motorized

use

S.F.

Coquille/Elk Ck Yes S.F. Coquille Low 0.1 None 

Gold Beach District

Game Lake Trail

#1169

3, 4,

& 5

Trail‐

prohibit

motorized

use

Lawson‐Illinois

River; Lower

Illinois River

Yes Yes Low 0.87 7 

Lawson Creek

Trail

# 1173 3 &

4

Trail‐

prohibit

motorized

use

Lawson‐Illinois

River; Lower

Illinois River

Yes Yes Low 0.6 None 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Lawson Creek

Trail

# 1173

4

Trail‐

prohibit

motorized

use

Lawson‐Illinois

River; Lower

Illinois River

Yes Yes Low 0.38 2 

Lawson

Connector Trail

4

Trail‐

prohibit

motorized

use

Lawson‐Illinois

River; Lower

Illinois River

Yes Yes Low 0.31

4 

Shasta Costa

Creek Trail

4

Trail‐

prohibit

motorized

use

Rogue River,

Illahe

& Shasta

Costa

Shasta

Costa

Shasta

Costa Low 0.05 None 

Nancy Creek

&

Shasta Costa

Creek Trails

4

Trail‐

prohibit

motorized

use

Illinois River,

Indigo

& N.F.

Indigo

Yes Illinois River Low 2.28 14 

Road 3680409

(Game Lake) 3 Conversion to Trail Lawson‐Illinois River; Lawson Creek Yes Yes Low None None 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Roads 3680351,

353

(Lawson/Fairvie

w)

3 Conversion

to Trail

Lawson‐Illinois

River;Lawson

Creek

Yes Yes Low None None 

Roads

3313103,36801

90,195,220

(Signal Buttes)

3 & 5 Conversion

to Trail

Hunter Creek,

Lower Rogue,

Quosatana

Portions

of

Quosata

na

Hunter and

Lower

Rogue

Low 0.53 5 

Roads 3313110,

117 (Kimball

Hill)

3 & 5 Conversion

to Trail Quosatana Yes Rogue River Low 0.6 for Alt 3 & 0.08 for Alt 5

6 for Alt 3 & N

for Alt 5 

Red Flat Trail

4

Prohibit

Motorized

Use

Hunter

Creek/Upper

Hunter

No Hunter Ck None None 

Trail

# 1103

4

Prohibit

Motorized

Use

Chetco

River/Eagle

Creek

No Chetco None None 

Silver Lake Trail

#1184

3, 4,

& 5

Prohibit

Motorized

Use

Silver Creek,

Upper Silver

Creek

Yes U. Silver Ck Low 0.68 3 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Hobson Horn

Trail #1166

4

Prohibit

Motorized

Use

Illinois River,

Lawson,

Indigo, N.F.

Indigo, Silver,

N.F. Silver

Yes

Illinois

River, N.F.

Silver

Low 0.76 8 

Fish Hook Peak

Trail

# 1180

4

Prohibit

Motorized

Use

Indigo, West

Fk. Indigo Ck. Yes Illinois River Low None None 

Taylor Creek

Trail #1142, Big

Pine Spur Trail

#1142A, Trail

#1157, Onion

Way Trail

#1281, Secret

Way #1282A

3, 4,

& 5

Prohibit

Motorized

Use

Briggs Creek,

Upper Briggs

Creek

No Briggs Moderate 2.35 6 

Swede Creek

Trail

3, 4,

& 5

Prohibit

Motorized

Use

Briggs Creek,

Lower Briggs No Briggs Moderate 0.5 3 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Road 2600050

4

Prohibit

Motorized

Use

Silver Creek,

Upper Silver

Creek

Yes Silver Ck Low 0.22 3 

Trail

#1146,1132,

Dutchy/Chance

Ck

4

Prohibit

Motorized

Use

Silver Creek,

Upper Silver

Creek, Briggs

Ck, Upper

Briggs Ck

Silver Ck Silver Ck, Briggs Ck Moderate 0.89 2 

Trail 132, 1135,

1143, Red Dog,

Orion

4

Prohibit

Motorized

Use

Briggs Ck,

Lower Briggs

and Upper

Briggs

No Briggs Ck Moderate 10 20 

Wild Rivers District

Road 4201016

(Eight Dollar

Mtn

3, 4,&

5

Prohibit

Motorized

Use

Deer Ck,

Lower Deer

Ck, Josephine,

& Sixmile

No

Deer Ck,

Illinois

River

Moderate/L

ow 2 6 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Roads

4300910,920,9

25,4300011

3, 4,

& 5

Prohibit

Motorized

Use

Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 0.98 3 

Roads 4300920,

011 (Botanical

Area Rds)

4

Prohibit

Motorized

Use

Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 0.83 1

Roads 421029

(Botanical Area

Rds)

4

Prohibit

Motorized

Use

Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 1 3 

Road 4300910

(Wetlands)

3, 4,

& 5

Prohibit

Motorized

Use

Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 1.56

4 

Roads

4300920,011

(Wetlands)

3, 4,

& 5

Prohibit

Mixed Use Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 0.83 1 

Roads 4201029

(Botanical Area)

3, 4,

& 5

Prohibit

Mixed Use Josephine Ck No

Fiddler,

Canyon,

&

Illinois

River

Low 1 8 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Roads

4201844,846,847,4103087,25

24048,2524015

4

Prohibit

Motorized

Use

Illinois,

Josephine,

Sixmile, Baker,

Briggs, Lwr

Briggs, Deer,

Lwr Deer

No Illinois Low 0.05 1 

Road 4402494

(Biscuit Hill

Trail)

3 Conversion

to Trail

N.F. Smith

River, Baldface

Ck

No Rough

&

Ready Ck Low None None 

Roads 4400445,

460, 480, 485

(Botanical

Areas)

3, 4,

& 5

Prohibit

Motorized

Use

Illinois, Rough

and Ready Ck No Rough

&

Ready Ck

Low/Moder

ate

0.3 2 

Roads 4402019,

112,450,172,20

6,259A,550

4

Prohibit

Motorized

Use

N.F. Smith

River, Baldface

Ck, Diamind,

W.F. Illinois,

Rough&Ready

Baldface

Ck

W.F. Illinois

River Low 0.08 None 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Bolan Lake Trail

#1245

3, 4,

& 5

Prohibit

Motorized

Use

Sucker Creek No Sucker Ck Moderate None None 

Mt. Elijah Trail

# 1206

3, 4,

& 5

Prohibit

Motorized

Use

Sucker Creek

Upper

Sucker

Ck

Sucker Ck Low/Moder

ate

0.3 2 

Elk Creek Trail

#1230

4

Prohibit

Motorized

Use

Sucker Creek,

Grayback Ck

Grayback

Ck

Grayback

Ck Low 0.8

4 

Boundary Trail

#1207, 903, 907

4

Prohibit

Motorized

Use

Applegate,

Steve

&

Sturgis,

Carberry Ck

Sucker

Ck None Low 1.59 8 

Siskiyou Mountains District

Horse Camp

Trail #958

3, 4,

& 5

Prohibit

Motorized

Use

Applegate,

Butte and

Middle Fork

No None Low 1.1

4 

Cook and Green

Trail #959

4

Prohibit

Motorized

Use

Applegate

River No None Low None 20 
Draft Supplemental EIS APPENDIX D 

Watershed and Soil Characteristics Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Road or Trail Alt(s) Proposed Activity Watershed (5th and 6th fields) Key Water‐ shed Listed Streams CWE risk rating Miles in Riparian Reserve Ephemeral Str

Crossings 

Penn Sled Trail 3 & 5

Authorize

Motorized

Use

Applegate,

Squaw Ck No None Moderate None None 

Little Grayback

Trail #921

4

Prohibit

Motorized

Use

Applegate,

Squaw Ck No None Moderate 0.72 8 

Mule Mtn Trails

#918, 919, 920

4

Prohibit

Motorized

Use

Applegate,

Palmer Ck Yes Applegate Low 4.86 19 

High Cascades District

High Cascades

Play Area 3

Allow Off‐Rd

Motorized

Use

Big Butte,

Clarks Fork‐

Fourbit Ck

No None Moderate None None 
Draft Supplemental EIS APPENDIX D Page D-11 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Effects Mechanisms for Fisheries and Aquatic Species 

General effects related to roads and motorized trails located within Riparian Reserves are 

detailed below in Figures 1, 2, and 3. Information displayed in these diagrams is supported by 

Gucinski et al. 2001, Waters 1995, Furniss et al. 1991, Hausle and Coble 1976, and Cordone and 

Kelley 1961. It should be noted that none of the alternatives would result in measurable 

increases from road and motorized trail related impacts to aquatic habitat beyond what is 

currently occurring. 

Figure D-1. Road and Motorized Trail Related Sediment Deposition Effects 
Draft Supplemental EIS APPENDIX D Page D-12 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Figure D-2. Road and Motorized Trail Related Suspended Sediment Effects

Figure D-3. Potential Effects from Roads and Motorized Trails Located Within a Riparian 

Reserve 

 
Draft Supplemental EIS APPENDIX D Page D-13 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Incorporated Best Management Practices (BMPs, USDA Forest Service, 1988) 
Draft Supplemental EIS APPENDIX D Page D-14 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
Draft Supplemental EIS APPENDIX D Page D-15 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
Draft Supplemental EIS APPENDIX D Page D-24 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
Draft Supplemental EIS APPENDIX D Page D-26 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 
Draft Supplemental EIS APPENDIX D Page D-27 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

 
Draft Supplemental EIS APPENDIX D Page D-28 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

SOILS 

The geographic scope for the assessment of the soil resource conditions and potential effects is 

the entire Rogue River-Siskiyou National Forest. The Rogue River-Siskiyou National Forest is 

divided into five districts: the analysis for the soil resource is organized, analyzed, and discussed 

for each of the districts. 

The following tables present the soils potentially affected by each of the proposed activities 

associated with the Proposed Action (Alternative 3) 

Table 1. Gold Beach RD. Soils affected by each proposed activity that would result in a 

change in impact to soils. 

Proposed 

Activity 

Soil 

Types1

Soil Characteristics

Convert 

maintenance 

level 1 roads 

to motorized 

trails 

55F 

56F 

73F 

78G 

79G 

87F 

91F 

103D,E 

124E 

135F 

141G 

180F 

207E 

225E 

228F 

240E 

241E 

255E 

262F,G 

263G

55F: Cedarcamp-Snowcamp-Rock outcrop complex, 30-60% north 

slopes. Very bouldery loams and cobbly clay loams, well drained, 

formed from serpentinitic peridotite or meta-igneous rock. Hazard of 

water erosion moderate or severe. Associated with backslopes, ridge 

crests, shoulders. 

56F: Cedarcamp-Snowcamp-Rock outcrop complex, 30-60% south 

slopes. Similar to 55F. 

73F: Deadline-Barkshanty-Nailkeg complex, 30-60% south slopes. 

Channery loams, well drained, formed from schist or phyllite, depth to 

bedrock 20-60+ inches. Hazard of water erosion moderate or severe. 

Associated with backslopes, stable benches, narrow summits, 

shoulders. 

78G: Deadline-Nailkeg complex, 60-90% north slopes. Similar to 

73F, with hazard of water erosion very severe. 

79G: Deadline-Nailkeg complex, 60-90% south slopes. Similar to 

78G. 

87F: Digger-Remote-Rock outcrop complex, warm, 30-60% south 

slopes. Similar to 88F, with 25% rock outcrop. 

91F: Digger-Umpcoos-Dystrochrepts complex, warm, 30-60% south 

slopes. Described above. 

103D, 103E: Edson-Barkshanty complex, 0-15%, 15-30% slopes. 

Channery loams and clay loams, well drained, formed in schist or 

phyllite, depth to bedrock 60+ inches. Hazard of water erosion slight. 

Associated with concave and convex areas of summits. 

124E: Gamelake-Tincup complex, 0-30% slopes. Very gravelly and 

very cobbly loams, well drained, formed in metasedimentary or 

metavolcanic rock, depth to bedrock 20-60+ inches. Hazard of water 

erosion moderate. Associated with concave and convex areas of 

summits.

135F: Greggo-Mislatnah-Rock outcrop complex, 30-60% south 

slopes. Cobbly clay loams, well drained, formed from serpentinitic 

peridotite or other serpentinitic rock, depth to bedrock 10-40 inches. 

Hazard of water erosion severe. Associated with backslopes, narrow 

summits, shoulders and ridge crests.

141G: Haplumbrepts-Rock outcrop-Rubble land complex, 60-100% 

north slopes. Extremely gravelly sandy loams, well drained or 

somewhat excessively drained, formed from intrusive igneous rock, 

depth to bedrock 20-70 inches. Hazard of water erosion very severe. 

Associated with backslopes, ridge crests, shoulders. 

180F: Described above. 
Draft Supplemental EIS APPENDIX D Page D-29 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

207E: Remote-Digger-Rock outcrop complex, warm, 3-30% slopes. 

Similar to 87F, with 20% rock outcrop. 

225E: Saddlepeak-Threetrees complex, 15-30% slopes. Very 

channery loams, well drained, formed from schist or phyllite, depth to 

bedrock 20-60+ inches. Hazard of water erosion moderate. 

Associated with concave and convex areas of summits. 

228F: Saddlepeak-Threetrees-Scalerock complex, 30-60% north 

slopes. Very channery loams, well drained, formed in schist or 

phyllite, depth to bedrock 10-60+ inches. Hazard of water erosion 

moderate or severe. Associated with backslopes, narrow summits and 

shoulders. 

240E: Snowcamp-Cedarcamp-Flycatcher complex, 0-30% slopes. 

Very gravelly and very cobbly loams, well drained, formed in 

serpentinitic peridotite or meta-igneous rock, depth to bedrock 10-60+ 

inches. Hazard of water erosion moderate or severe. Associated with 

concave and convex areas of summits, shoulders and knobs. 

241E: Snowcamp-Cedarcamp-Rock outcrop complex, 0-30% slopes. 

Very bouldery loams, well drained, formed in sepentinitic peridotite or 

meta-igneous rock, depth to bedrock 20-60+ inches. Hazard of water 

erosion moderate. Associated with concave and convex areas of 

summits, ridge crests and shoulders. 

255E: Swedeheaven-Quailprairie-Sankey complex, 0-30% slopes. 

Gravelly loams and very gravelly sandy clay loams, well drained, 

formed in metasedimentary or metavolcanic rock, depth to bedrock 10-

60+ inches. Hazard of water erosion moderate or severe. Associated 

with concave and convex areas of summits, shoulders and knobs. 

262F, 262G: Threetrees-Saddlepeak-Scalerock complex, 30-60%, 

60-90% slopes. Very channery loams, well drained, formed in schist 

or phyllite, depth to bedrock 10-60+ inches. Hazard of water erosion 

moderate or severe, very severe. Associated with backslopes, narrow 

summits and shoulders. 

263G: Threetrees-Saddlepeak-Scalerock complex, 60-90% north 

slopes. Similar to 262G, with very severe water erosion hazard. 

New 

motorized 

trail 

construction 

17E 

87F 

103E

17E: Barkshanty-Nailkeg-Rock outcrop complex, 0-30% slopes. 

Channery loams, well drained, formed in schist or phyllite, depth to 

bedrock 20-60+ inches. Hazard of water erosion moderate. 

Associated with concave and convex areas of summits, ridge crests, 

shoulders. 

87F: Described above. 

103E: Described above. 

Close trails to 

motorized 

use 

9F,G 

13G 

54F 

90E 

91F 

104E 

112A 

132F 

158F 

180F 

182F 

204E 

214 

241E

9F, 9G: Atring-Kanid-Vermisa complex, 30-60%, 60-90% south 

slopes. Very gravelly loams, well drained and somewhat excessively 

drained, formed in metasedimentary rock, depth to bedrock 10-60 

inches. Hazard of water erosion moderate or severe, very severe. 

Associated with backslopes, narrow summits and shoulders. 

13G: Atring-Vermisa complex, 60-90% north slopes. Very gravelly 

loams, well drained and somewhat excessively drained, formed in 

metasedimentary rock, depth to bedrock 10-40 inches. Hazard of 

water erosion very severe. Associated with backslopes, narrow 

summits and shoulders. 

54F: Cedarcamp-Snowcamp-Flycatcher complex, 30-60% south 

slopes. Very gravelly and very cobbly loams, well drained, formed in 

serpentinitic peridotite or meta-igneous rock , depth to bedrock 10-60+ 

inches. Hazard of water erosion moderate or severe. Associated with 

backslopes, narrow summits and shoulders. 
Draft Supplemental EIS APPENDIX D Page D-30 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

90E: Digger-Remote complex, warm, 3-30% slopes. Gravelly loams, 

well drained, formed in metasedimentary or metvolcanic rock, depth to 

bedrock 20-60+ inches. Hazard of water erosion moderate. 

Associated with convex and gently sloping areas of summits. 

91F: Described above. 

104E: Eightlar-Gravecreek-Pearsoll complex, 3-30% slopes. Very 

stony clay loam, very cobbly loam, very cobbly clay loam, well drained, 

formed in serpentinitic peridotite or other serpentinitic rock, depth to 

bedrock 10-60+ inches. Hazard of water erosion moderate or severe. 

Associated with concave and convex areas of summits, shoulders, 

knobs. 

112A: Evans silt loam, 0-3% slopes. Silt loam, well drained, formed 

in alluvium, depth to bedrock 60+ inches. Hazard of water erosion 

slight except during flooding. Associated with floodplains. 

132F: Gravecreek-Eightlar-Pearsoll complex, 30-60% south slopes. 

Similar to 104E, with hazard for water erosion moderate to very 

severe. 

158F: Kanid-Acker-Atring complex, 30-60% north slopes. Gravelly 

and very gravelly loams, well drained, formed in metasedimentary 

rock, depth to bedrock 20-60+ inches. Hazard of water erosion 

moderate or severe. Associated with backslopes and footslopes. 

180F: Described above. 

182F: Mislatnah-Redflat-Greggo complex, 30-60% north slopes. 

Cobbly clay loams, gravelly loam, well drained, formed in serpentinitic 

peridotite or other serpentinitic rock, depth to bedrock 10-60+ inches. 

Hazard of water erosion moderate or severe. Associated with 

backslopes, footslopes, narrow summits, shoulders. 

204E: Redflat-Mislatna-Greggo complex, 0-30% slopes. Similar to 

182F, but associated with concave and convex areas of summits, 

shoulders, knobs. 

214: Riverwash. Associated with areas adjacent to rivers and 

streams that consist of sand and gravel and do not support vegetation. 

Frequently flooded, with very severe hazard of water erosion. 

241E: Described above. 

1

Curry County Soil Survey (USDA NRCS, 2005) 

Table 2. Wild Rivers RD. Soils affected by each proposed activity that would result in a 

change in impact to soils. 

Proposed 

Activity 

Soil 

Types Soil Characteristics 

Convert 

maintenance 

level 1 roads 

to motorized 

trails

58F,G2

193E1

58F, 58G: Pearsoll-Rock outcrop complex, 20-60%, 60-90% slopes. 

Extremely stony clay loam and rock outcrop, shallow, well drained, 

formed in colluvium derived dominantly from serpentinite and peridotite. 

Depth to serpentine bedrock 10-20 inches. Hazard of water erosion is 

high to very high. Associated with mountainsides and highly dissected 

mountainsides. 

193E: Perdin-Rock outcrop complex, 5-30% slopes. Cobbly loams, 

gravelly clay loams, and rock outcrop, well drained, formed from 

serpentinitic peridotite. Depth to bedrock 20-40 inches. Hazard of water 

erosion is moderate or severe. Associated with convex areas of summits.

Close trails 

to motorized 

use

42

7F2 

8G2

9G2 

10F2 

23G2 

24G2 

4: Banning loam, 0-3% slopes. Loams and clay loams, deep, somewhat 

poorly drained, formed in alluvium derived from metamorphic, granitic, 

and ultramafic rock. Depth to bedrock 60+ inches, seasonal high water 

table, hazard of water erosion is slight. Associated with alluvial fans and 

drainageways. 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

25E2

26F2 

47E2 

48F2 

61B,D2

72F2 

80G2 

81G2 

82G2 

7F: Beekman-Colestine complex, 50-75% south slopes. Gravelly loam, 

moderately deep, well drained, formed in colluvium derived from altered 

sedimentary and extrusive igneous rock. Depth to bedrock 20-40 inches, 

hazard of water erosion is high. Associated with mountainsides. 

8G: Beekman-Vermisa complex, 60-100% north slopes. Gravelly loam 

and extremely gravelly loam, moderately deep to shallow, well drained to 

somewhat excessively well drained, formed in colluvium derived from 

altered sedimentary and extrusive igneous rock. Depth to bedrock 10-40 

inches, hazard of water erosion is high. Associated with mountains. 

9G: Beekman-Vermisa complex, 60-100% south slopes. Similar to 8G. 

10F: Bigelow very gravelly sandy loam, 35-65% slopes. Deep, well 

drained, formed in colluvium from granitic rock. Depth to compacted 

glacial till approx. 39 inches, hazard of water erosion is high. Associated 

with concave areas on mountainsides and glacial basins. 

23G: Crannler very stony sandy loam, 50-90% slopes. Moderately deep, 

somewhat excessively drained, formed in colluvium and residuum from 

granitic roak. Depth to bedrock 20-40 inches, hazard of water erosion is 

high. Associated with convex slopes of mountains. 

24G: Crannler-Rock outcrop complex, 50-100% slopes. Similar to 23G, 

but with 30% rock outcrop. 

25E: Cryaquepts, 0-30% slopes. Silt loam, moderately deep or deep, 

somewhat poorly drained or poorly drained, formed in alluvium and 

colluvium from granitic rock. Depth to bedrock 20-60+ inches. 

Associated with depressional areas, drainage basins, and mountainsides. 

26F: Cryumbrepts, very steep, 20-75% slopes. Gravelly sandy loam, 

very shallow to moderately deep, well drained and somewhat excessively 

drained, formed in colluvium from granitic rock. Depth to bedrock 7-40 

inches. Associated with mountainsides. 

47E: Josephine gravelly loam, 20-35% slopes. Similar to 48F, with 

hazard of water erosion moderate. Associated with mountainsides and 

ridges. 

48F: Josephine gravelly loam, 35-55% north slopes. Deep, well drained, 

formed in colluvium and residuum from altered sedimentary and extrusive 

igneous rock. Hazard of water erosion is high. Depth to bedrock 40-60 

inches. Associated with mountainsides. 

61B, 61D: Pollard loam, 2-7%, 12-20% slopes. Deep, well drained, 

formed in colluvium and alluvium from altered sedimentary and extrusive 

igneous rock. Hazard of water erosion slight, moderate, depth to bedrock 

60+ inches. Associated with terraces, saddles, and hills, mountains. 

72F: Speaker-Josephine gravelly loams, 35-55% south slopes. 

Moderately deep to deep, well drained, formed in colluvium, residuum 

from altered sedimentary and extrusive igneous rock. Hazard of water 

erosion high, depth to bedrock 20-60 inches. Associated with mountains. 

80G: Vermisa-Beekman complex, 60-100% north slopes. Similar to 8G. 

81G: Vermisa-Beekman complex, 60-100% south slopes. Similar to 8G. 

82G: Vermisa-Rock outcrop complex, 60-100% south slopes. Similar to 

8G but with 30% rock outcrop., shallow, somewhat excessively drained. 

1

Curry County Soil Survey (USDA NRCS, 2005) 

2

Josephine County Soil Survey (USDA NRCS, 1983) 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

Table 3. Siskiyou Mountains RD. Soils affected by each proposed activity that would 

result in a change in impact to soils. 

Proposed 

Activity

Soil Landtypes3 Soil Characteristics

New 

motorized 

trail 

construction

69 

619 (65% 61 / 35% 

69) 

689 (60% 68 / 40% 

69)

69: Soils are sandy loams, loams and silty clay loams 

containing 50-80% gravel, cobble and stone, forming in 

unconsolidated, non-cohesive, landslide debris, 

somewhat poorly to well drained, Stability Class V (very 

unstable). Depth to bedrock from 6 to 12+ feet. 

Associated with steep and uneven landslide toe slope 

positions with 45-80% slopes. 

68: Soils are similar to 69 soils, with Stability Class III 

(moderately stable). Associated with gently rolling to 

moderately steep, hummocky landslide mid-slopes with 

15-45% slopes. 

61: Soils are loams and fine sandy loams containing 50-

85% platy gravels and cobbles, forming in colluvium, 

somewhat excessively drained, Stability Class III 

(moderately stable). Depth to bedrock from 1-3 feet. 

Associated with slightly to moderately dissected, long, 

straight, very steep side slopes with 60-90% slopes.

Close trails 

to motorized 

use

57 

93 

99 

542 (65% 54 / 35% 

92) 

593 (60% 59 / 40% 

93) 

793 (35% 70 / 35% 59 

/ 30% 93)

54: Soils are sandy loams and loams containing 35-65% 

gravel, cobble and stone, forming in glacial till deposits, 

well drained, Stability Class III and IV (moderately stable 

to unstable). Depth to bedrock 6-12 feet. Associated 

with moderately to highly dissected very steep slopes 

associated with glacial trough walls with 60-90% slopes. 

57: Soils are loams and clay loams containing 50-90% 

gravel, cobble and stone, forming in residuum and 

colluvium, well drained, Stability Class II (stable). Depth 

to bedrock from 2-4 feet. Associated with side slopes 

and ridges associated with ultramafic, serpentinized 

igneous intrusions with 20-70% slopes. 

59: Soils are loams, clay loams and clays containing 

50+/-% cobble and stone, forming in colluvium (high 

percentage mafic coarse fragments), well drained, 

Stability Class IV and V (unstable to very unstable). 

Depth to bedrock 6-12+ feet. Associated with 

moderately steep to steep, somewhat rounded and 

dissected slopes occurring along fault zones or in 

association with mafic or ultra mafic intrusions with 45-

75% slopes. 

70: Soils are mostly loams and clay loams containing 

45-60% gravel and cobble, forming in colluvium, well 

drained, Stability Class III and IV (moderately unstable to 

unstable). Depth to bedrock 2-4 feet. Associated with 

highly dissected, long, steep to very steep, straight side 

slopes with 55-80% slopes.

92: Perennially wet alder glades with wet soils of 

variable composition and slope, commonly in draws and 

basins. 

93: Large rock outcrops and associated talus fields, 

various kinds of rock represented, commonly occur along 

ridge tops and southern exposures. 
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Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

99: Old landflows and landslide deposits consisting of 

interconnected steep slopes and benches, formed by 

mass movement processes, result in churned soil 

deposits with poor to excessive drainage. Highly variable 

site-to-site.

3

SRI for the Rogue River National Forest (Badura and Jahn, 1977) 

Table 4. High Cascades RD. Soils affected by each proposed activity that would result in 

a change in impact to soils. 

Proposed Activity Soil 

Landtypes3 Soil Characteristics 

Develop motorized 

play area 

24 Soils are sandy loams forming in cindery glaciofluvial deposits, 

excessively drained, Stability Class I (very stable). Depth to 

bedrock generally greater than 12 feet. Associated with sandy 

flats of glaciofluvial origin. 

3

SRI for the Rogue River National Forest (Badura and Jahn, 1977) 

 
Draft Supplemental EIS APPENDIX D Page D-34 

Watershed and Soil Characteristics 

Motorized Vehicle Use on the Rogue River-Siskiyou National Forest 

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