LOCATION NORTHWATER CO+ID
Established Series
Rev. DKA/KP
10/2026
NORTHWATER SERIES
The Northwater series consists of deep, well drained soils formed in colluvium over residuum from sedimentary and metasedimentary rocks. These soils are on mountain slopes, ridges, and valley floors. Slopes are 6 to 80 percent. Mean annual precipitation is about 575 mm, and mean annual temperature is about 4 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Pachic Palecryolls
TYPICAL PEDON: Northwater loam. (Colors are for dry soil unless otherwise noted.)
Oe--0 to 5 cm; moderately decomposed plant material.
A1--5 to 30 cm; brown (10YR 4/3) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; neutral; clear smooth boundary.
A2--30 to 69 cm; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; moderate fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; 10 percent gravel; neutral; clear wavy boundary.
Bt--69 to 132 cm; light brown (7.5YR 6/4) very channery clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, friable, sticky and plastic; common medium and coarse roots; common clay films and organic coats on faces of peds and on surfaces along pores; 50 percent channers; neutral; clear wavy boundary.
R--132 cm; fractured sandstone.
TYPE LOCATION: Garfield County, Colorado; 400 feet south and 150 feet west of the center of Sec. 12, T. 5 S., R. 96 W.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--2.0 to 6.4 degrees C
Thickness of mollic epipedon--51 to 137 cm
Depth to argillic--30 to 71 cm
Depth to bedrock--100 to 150 cm
Particle-size control section (weighted averages)
Clay content--18 to 35 percent
Total rock fragments--35 to 70 percent
O horizons (when present)
Texture--slightly or moderately decomposed plant material
Reaction--pH 4.0 to 5.5
Organic matter content--60 to 95 percent
Thickness--0 to 5 cm
A horizon
Hue--7.5 YR to 2.5Y
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3
Texture (less than 2 mm fraction)--loam, silt loam, very fine sandy loam
Clay content--5 to 27 percent
Rock fragments--0 to 80 percent-0 to 37 percent gravel or channer, 0 to 35 percent cobbles, 0 to 14 percent stones, 0 to 35 percent boulders
Reaction--pH 6.1 to 7.8
Thickness--51 to 89 cm
Bt horizon
Hue--7.5 to 2.5 Y
Value--4 to 7 dry, 3 through 5 moist
Chroma--3 or 4
Texture (less than 2 mm fraction)--loam, clay loam, sandy clay loam
Clay content--10 to 35 percent
Rock fragments--35 to 85 percent-0 to 60 percent gravel or channers, 0 to 60 percent cobbles, 5 to 30 percent stones, 0 to 35 percent boulders
Reaction--pH 6.1 to 7.8
Thickness--51 to 127 cm
C horizon (when present)
Hue--7.5 to 2.5Y
Clay content--12 to 20 percent
Rock fragments--35 to 60 percent-4 to 11 percent gravel, 20 to 30 percent cobbles, 8 to 15 percent boulders
Reaction--pH 6.1 to 7.3
COMPETING SERIES:
Charcol (UT)--have argillic horizons that start 102 to 152 cm below the surface
Flygare (UT)--are very deep to bedrock
Parvis (ID)--are very deep to bedrock
Rapid (ID)--are very deep to bedrock
GEOGRAPHIC SETTING:
Landform--mountain slopes, ridgesand valley floors
Elevation--1,620 to 3,410 meters
Slope--6 to 80 percent
Parent material--colluvium over residuum from sedimentary and metasedimentary rocks
Mean annual precipitation--400 to 875 mm
Mean annual air temperature--1.1 to 5.6 degrees C
Frost-free period--30 to 80 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, 1.5 to 15.0 um/sec
USE AND VEGETATION: Northwater soils are primarily used for recreation, wildlife habitat, and limited livestock grazing. The potential native vegetation is snowberry, Columbia needlegrass, nodding brome, elk sedge, slender wheatgrass and Thurber's fescue.
DISTRIBUTION AND EXTENT: Northwater soils are of moderate extent in Colorado and southeastern Idaho; MLRAs 13, 47, and 48A.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Paonia Area, Colorado, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon--0 to 69 cm (A1 and A2 horizons)
Argillic horizon--69 to 132 cm (Bt horizon)
Lithic contact--132 cm (R horizon)
Particle-size control section--69 to 119 cm
Northwater soils have a cryic temperature regime and an udic moisture regime.
Taxonomic version: Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.