LOCATION KOPPES ID

Established Series
Rev. JFA-BDG-RJS
03/2016

KOPPES SERIES

The Koppes series consists of deep and very deep, somewhat excessively drained soils that formed in colluvium derived from granodiorite. These soils are on mountain slopes and ridges. Slopes are 20 to 60 percent. Mean annual precipitation is about 775 mm, and the mean annul temperature is about 4.4 degrees C.

TAXONOMIC CLASS: Sandy, mixed Xeric Haplocryolls

TYPICAL PEDON: Koppes gravelly loamy coarse sand - Douglas-fir and Ponderosa pine. (Colors are for dry soil unless otherwise noted.)

Oe--0 to 3 cm; very dark brown (10YR 2/2) moderately decomposed needles, leaves, twigs, and cones; slightly acid (pH 6.3); abrupt wavy boundary. (0 to 13 cm thick.)

A1--3 to 15 cm; grayish brown (10YR 5/2) gravelly loamy coarse sand, very dark grayish brown (10YR 3/2), very dark brown (10YR 2/2) crushed, moist; weak very fine and fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine and fine, and few medium roots; many micro interstitial and very fine tubular pores; 20 percent of angular gravel less than 5mm. across; slightly acid (pH 6.1); clear wavy boundary. (10 to 20 cm thick)

A2--15 to 33 cm; grayish brown (10YR 5/2) loamy coarse sand, very dark grayish brown (10YR 3/2) moist; weak very fine and fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine and fine and common medium roots; many micro interstitial and common fine tubular pores; 10 percent of angular gravel less than 5 mm. across; slightly acid (pH 6.1); clear wavy boundary. (15 to 20 cm thick)

C1--33 to 46 cm; brown (10YR 5/3) light brownish gray (10YR 6/2) crushed, loamy coarse sand, dark grayish brown (10YR 4/2) moist; single grain structure; soft, very friable, nonsticky, nonplastic; common very fine, fine and medium roots; many micro interstitial, common fine and medium and few coarse tubular pores; 10 percent of angular gravel mostly less than 5 mm. across; moderately acid (pH 6.0); clear irregular boundary. (10 to 38 cm thick)

C2--46 to 66 cm; pale brown (10YR 6/3) loamy coarse sand, brown (10YR 4/3) moist; weak very fine and fine granular structure; soft, very friable, nonsticky, nonplastic; common very fine and fine and few medium roots; many micro interstitial and very fine tubular pores; 10 percent of angular fine gravel; moderately acid (pH 6.0); gradual irregular boundary. (13 to 38 cm)

C3--66 to 86 cm; pale brown (10YR 6/3) loamy coarse sand, brown (10YR 4/3) moist; single grain structure; soft, very friable, nonsticky, nonplastic; common very fine and fine and few medium roots; many micro interstitial, common very fine and few medium tubular pores; very slight clay bridging; 10 percent of angular fine gravel; moderately acid (pH 5.9); gradual irregular boundary. (0 to 25 cm thick)

C4--86 to 104 cm; pale brown (10YR 6/3) gravelly loamy coarse sand, brown (10YR 4/3) moist; single grain structure; soft, very friable, nonsticky, nonplastic; common very fine and fine, few medium and coarse roots; many micro interstitial and common very fine tubular pores; at least one 4 mm. more clayey lamella; some clay bridging, clay films perhaps in thin discontinuous cavities; 10 percent of angular fine and medium gravel, 5 percent of coarse gravel; moderately acid (pH 5.8); clear irregular boundary. (0 to 25 cm thick)

C5--104 to 130 cm; pale brown (10YR 6/3) gravelly coarse sand, dark grayish brown (10YR 4/2) moist; moderately stained;, massive; slightly hard, very friable, nonsticky, nonplastic; few very fine and fine roots; many micro interstitial pores; 30 percent of angular gravel that can be broken in the hand.

TYPE LOCATION: Boise County, Idaho; NW1/4 NE1/4, Sec. 9, T. 9 N.,
R. 5 E.; Garden Valley Ranger District, Boise National Forest, Latitude - 44 degrees, 7 minutes, 49.5 seconds, North; Longitude - 115 degrees, 52 minutes, 0.2 seconds, West.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 3.3 to 7.2 degrees C
Mean summer soil temperature at a depth of 50 cm ranges - 12.8 to 15.0 degrees C. (without an O horizon)
Soil moisture - dry in all horizons between 60 and 90 cm for 60 consecutive days in more than 7 out of 10 years
Soil depth - 100 to 180 cm to a lithic contact (deep or very deep)
Particle-size Control section - loamy sand or coarser throughout, contains less than 35 percent of coarse fragments
Mollic epipedon - 18 to 40 cm thick

A horizons:
Value - 4 or 5 dry and 2 or 3 moist
Chroma - 1 or 2 dry or moist
Textures - loamy coarse sand or coarse sandy loam
Clay content - 2 to 15 percent
Rock fragment content - 5 to 20 percent gravel, 0 to 5 percent cobbles, 5 to 20 percent total rock fragments
Reaction - pH 5.6 to 7.3

C horizons:
Value - 5.5 to 8 dry and 3.5 to 6 moist
Chroma - 2 to 3 dry or moist
Textures - coarse sand, sand, loamy coarse sand or loamy sand
Clay content - 0 to 12 percent
Rock fragments - 5 to 35 percent gravel (mostly less than 5 mm), 0 to 10 percent cobbles, 0 to 5 percent stones, 5 to 50 percent total rock fragments
Reaction - pH 5.6 to 7.3

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Landform - mountain slopes, ridges
Elevation - 1,370 to 2,135 meters
Slope - 20 to 60 percent
Slope shape - linear, concave
Aspects - all
Parent material - formed in colluvium derived from granodiorite
Mean annual precipitation - 625 to 975 mm
Mean annual air temperature - 3.0 to 7.0 degrees C
Frost-free period - 30 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: These include Coski, Pyle, Quartzburg, Toiyabe, and Scriver soils. Coski soils are coasre-loamy and occur on mountain and hill slopes. Pyle soils have lamellae and occur on mountain slopes and ridges. Quartzburg soils are sandy-skeletal and occur on mountain slopes and ridges. Toiyabe soils are less than 50 cm to bedrock and occur on mountain slopes and ridges. Scriver soils are deep to a paralithic contact and have lamellae. They occur on mountain slopes and fan remnants.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; very high saturated hydraulic conductivity.

USE AND VEGETATION: Used for forestry, watershed, wildlife, grazing and recreation. On northerly aspects, the main habitat types are Douglas-fir/ninebark, Douglas-fir-ponderosa pine/snowberry, and Douglas-fir/elk sedge. On southerly aspects, the main habitat types are ponderosa pine-bunchgrass, ponderosa pine/bitterbrush, and ponderosa pine/snowberry.

DISTRIBUTION AND EXTENT: Moderately extensive in the Idaho batholith of west-central Idaho. MLRA 43B.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Middle Fork Payette River Area, Idaho, 1969.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 3 to 33 cm (A1, A2 horizons)
Particle size control section - 28 to 103 cm (part of A2, C1, C2, C3, part of C4 horizons)

Additional Information:
This series was classified formerly as a Regosol. On 3/4/2009 this description was entered for the first time into the OSD files. Although it was established in 1969 it had never been in an electronic form.

3/1/2016 - Based on the soil moisture regime, the Koppes series taxonomic classification was changed from Typic Haplocryolls to Xeric Haplocryolls.

Koppes soils have a cryic temperature regime and a xeric moisture regime.

National Cooperative Soil Survey
U.S.A.