LOCATION KURRIE MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Ustic Glossocryalfs
TYPICAL PEDON: Kurrie very cobbly sandy loam, very bouldery, in forest (colors are for dry soil unless otherwise noted).
Oi--0 to 2 inches; partially decomposed needles, twigs and leaves.
A--2 to 6 inches; brown (10YR 5/3) very cobbly sandy loam, dark brown (10YR 3/3) moist; weak medium and fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and few fine and medium roots; many very fine and fine pores; 20 percent cobbles and 15 percent gravel; neutral (pH 6.6); clear wavy boundary. (0 to 5 inches thick)
E--6 to 11 inches; light gray (2.5Y 7/2) very cobbly sandy loam, grayish brown (2.5Y 5/2) moist; weak medium and fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine, common fine, and few medium and coarse roots; many very fine and fine pores; 5 percent stones, 20 percent cobbles, and 10 percent gravel; slightly acid (pH 6.1); clear wavy boundary. (4 to 10 inches thick)
E/Bt--11 to 25 inches; E part (80 percent) is light gray (2.5Y 7/2) very cobbly sandy loam, grayish brown (2.5Y 5/2) moist; B part (20 percent) is light yellowish brown (2.5Y 6/4) very cobbly sandy clay loam, olive brown (2.5Y 4/4) moist; weak medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and few fine, medium, and coarse roots; many very fine and fine tubular and interstitial pores; many faint clay films bridging sand grains in B part; 5 percent stones, 30 percent cobbles, and 10 percent gravel; slightly acid (pH 6.3); clear wavy boundary. (10 to 15 inches thick)
Bt--25 to 43 inches; light yellowish brown (2.5Y 6/4) very cobbly sandy clay loam, olive brown (2.5Y 4/4) moist; moderate medium and fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine and few fine, medium, and coarse roots; many very fine and few fine tubular pores; many faint clay films bridging sand grains; 30 percent cobbles and 10 percent gravel; slightly acid (pH 6.5); clear wavy boundary. (10 to 20 inches thick)
BC--43 to 48 inches; grayish brown (2.5Y 5/2) gravelly coarse sandy loam, dark grayish brown (2.5Y 4/2) moist; massive; soft, very friable, slightly sticky and nonplastic; common very fine and few fine roots; many very fine and few fine tubular and interstitial pores; 20 percent gravel; neutral (pH 6.8); clear wavy boundary. (0 to 15 inches thick)
Cr--48 to 55 inches; light brownish gray (2.5Y 6/2) decomposed granite bedrock (grus) that crushes to gravelly coarse sand; neutral (pH 6.8). (5 to 18 inches thick)
R--55 inches; hard granite bedrock.
TYPE LOCATION: Jefferson County, Montana; 2100 feet south and 1500 feet west of the NE corner of sec. 18, T. 9 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Soil Temperature - 38 to 42 degrees F.
Moisture control section - between 4 and 12 inches.
Depth to the Cr horizon - 40 to 58 inches.
Depth to R horizon - 43 to 60 inches.
Surface stones and boulders - 0 to 3 percent.
A Bt/E horizon is allowed.
The A horizon, when present, does not meet the thickness or color requirements of a mollic epipedon.
A horizon
Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: coarse sandy loam or sandy loam
Clay content: 10 to 20 percent
Rock fragments: 10 to 60 percent--0 to 10 percent stones, 0 to 25 percent cobbles, 10 to 25 percent gravel
Reaction: pH 6.1 to 7.3
E horizon
Hue: 10YR or 2.5Y
Value: 6, 7 or 8 dry, 4, 5 or 6 moist
Chroma: 1, 2 or 3
Texture: coarse sandy loam, sandy loam or sandy clay loam
Clay content: 10 to 25 percent
Rock fragments: 20 to 60 percent--0 to 10 percent stones, 10 to 30 percent cobbles, 10 to 20 percent gravel
Reaction: pH 6.1 to 7.3
E/Bt horizon
Hue: 10YR or 2.5Y
Value: E part: 6, 7 or 8 dry; 4, 5 or 6 moist
Bt part: 4, 5 or 6 dry; 3, 4 or 5 moist
Chroma: E part: 1, 2, 3 or 4; Bt part: 2, 3 or 4
Texture (mixed): coarse sandy loam, sandy loam or sandy clay loam
Clay content: 10 to 25 percent
Rock fragments: 20 to 60 percent--0 to 10 percent stones, 10 to 30 percent cobbles, 10 to 20 percent gravel
Reaction: pH 6.1 to 7.3
Bt horizon
Hue: 10YR or 2.5Y
Value: 4, 5 or 6 dry, 3, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: sandy loam, sandy clay loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 35 to 60 percent--0 to 5 percent stones, 25 to 35 percent cobbles, 10 to 20 percent gravel
Reaction: pH 6.1 to 7.3
BC horizon
Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture: coarse sandy loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 20 to 50 percent--0 to 10 percent cobbles, 20 to 40 percent gravel (mostly less than 10mm in diameter)
Reaction: pH 6.1 to 7.3
COMPETING SERIES:
Gambler (CO) - does not have a paralithic contact above the lithic contact; formed in residuum and colluvium from basalt, andesite and trachyte.
Granile (CO) - does not have a lithic contact above 60 inches.
Kebler (CO) - does not have a paralithic contact above the lithic contact.
Larand (CO) - does not have a lithic contact above 60 inches.
Leadville (CO) - does not have a lithic contact above 60 inches.
Macfarlane (CO) - does not have a lithic contact above 60 inches.
Tuckerville (CO) - does not have a lithic contact above 60 inches.
GEOGRAPHIC SETTING:
Landform- alluvial fans, ridges and sideslopes of mountains.
Elevation - 5,500 to 7,000 feet.
Slope - 15 to 60 percent.
Parent material - slope alluvium and colluvium from hard coarse grained granitic rock deposited over granite bedrock.
Climate - long, cold winters; moist springs; short, cool summers.
Mean annual precipitation - 15 to 24 inches.
Mean annual air temperature - 36 to 40 degrees F.
Frost-free period - 30 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Kurrie soils are primarily used for woodland, wildlife habitat and watershed. The potential native vegetation is mainly lodgepole pine, Douglas-fir, pinegrass, russet buffaloberry, white spiraea, kinnikinnick, heartleaf arnica, grouse whortleberry, clematis, alumroot, raceme pussytoes, and woodland strawberry.
DISTRIBUTION AND EXTENT: Kurrie soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Jefferson County, Montana, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 11 inches (Oi, A and E horizons);
Glossic horizon - from 11 to 25 inches (E/Bt horizon);
Argillic horizon - from 25 to 43 inches (Bt horizon);
Paralithic granite (grus) - from 48 to 55 inches (Cr horizon);
Lithic granite bedrock - 53 inches (R horizon); and a
Particle size control section - from 25 to 43 inches (Bt horizon).
Kurrie soils have a cryic temperature regime and an ustic moisture regime.
ADDITIONAL DATA: Soil interpretation records MT3078 and MT3079.