LOCATION HULLSGULCH IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aridic Argixerolls
TYPICAL PEDON: Hullsgulch loamy coarse sand -- on a 44 percent convex southwest-facing slope at 3,380 feet elevation in rangeland. When described on May 16, 1995, the soil was moist throughout. (Colors are for air-dry soil unless otherwise noted.)
A--0 to 5 inches; grayish brown (10YR 5/2) loamy coarse sand, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, few medium roots; many very fine and fine irregular pores; 5 percent fine gravel; neutral (pH 6.7); clear smooth boundary. (2 to 10 inches thick)
BA--5 to 12 inches; grayish brown (10YR 5/2) coarse sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to moderate fine and medium granular; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; common very fine and fine tubular pores; 5 percent fine gravel; neutral (pH 7.0); clear wavy boundary. (2 to 9 inches thick)
Bt1--12 to 19 inches; yellowish brown (10YR 5/4) sandy clay loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; very hard, friable, slightly sticky and slightly plastic, common very fine and fine roots; common very fine and fine tubular pores; common distinct clay films on faces of peds, in pores and bridging sand grains; 5 percent fine gravel; neutral (pH 7.1); clear wavy boundary.
Bt2--19 to 25 inches; light yellowish brown (10YR 6/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; common very fine and fine tubular pores; few distinct clay films on faces of peds, in pores and bridging sand grains; 10 percent fine gravel; neutral (pH 7.1); gradual wavy boundary.
Bt3--25 to 38 inches; very pale brown (10YR 7/4) coarse sandy loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; few distinct clay films in pores and bridging sand grains; 10 percent fine gravel; neutral (pH 7.2); clear wavy boundary. (combined Bt horizon - 22 to 54 inches thick)
E&Bt1--38 to 53 inches; (E material - 80% of horizon) very pale brown (10YR 8/3) loamy coarse sand, yellowish brown (10YR 5/4) moist; weak fine and medium subangular blocky structure parting to single grain; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; 10 percent fine gravel; neutral (pH 7.2); (Bt material) continuous lamellae; light yellowish brown (10YR 6/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; 2 to 10 mm thick and 4 to 10 inches apart; few distinct clay films bridging sand grains; clear smooth boundary. (12 to 25 inches thick)
E&Bt2--53 to 60 inches; (E material - 95% of horizon) very pale brown (10YR 8/3) fine gravelly coarse sand, pale brown (10YR 6/3) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine tubular pores; 15 percent fine gravel; neutral (pH 7.3); (Bt material) continuous lamellae; light yellowish brown (10YR 6/4) gravelly sandy clay loam, dark yellowish brown (10YR 4/4) moist; 2 to 10 mm thick and 6 to 12 inches apart; few distinct clay films bridging sand grains.
TYPE LOCATION: Ada County, Idaho; about 4.5 miles east and 4.5 miles north of Eagle; 2,480 feet north and 1,280 feet east of the southwest corner of section 19, T.5 N., R.2 E.; USGS Pearl Quadrangle; Latitude - 43 degrees, 45 minutes, 23 seconds N. and Longitude - 116 degrees, 16 minutes, 10 seconds W.; NAD 27.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 20 inches
Depth to base of argillic horizon - greater than 25 inches
Depth to bedrock - greater than 60 inches
Particle-size control section - 18 to 30 percent clay; greater than 20 percent medium and coarse sand; 0 to 15 percent gravel (dominantly fine)
Moisture control section - moist less than 90 consecutive days when the soil temperature is greater than 47 degrees F.
Average annual soil temperature - 50 to 54 degrees F.
A and BA horizons
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Rock fragments - 0 to 10 percent gravel
Reaction - slightly acid or neutral
Bt horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 3 or 4 dry or moist
Texture - SCL or COSL
Clay content - 18 to 30 percent
Rock fragments - 0 to 15 percent gravel
Reaction - slightly acid or neutral
E&Bt1 horizon
Clay content (weighted average) - 10 to 20 percent
Rock fragments (weighted average) - 10 to 25 percent gravel
- E material (70 to 85 percent)
Value - 7 or 8 dry, 5 or 6 moist
Chroma - 3 or 4 dry or moist
Texture - COSL or LCOS
Clay content - 8 to 18 percent
Reaction - slightly acid or neutral
- Bt material (lamellae)
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Texture - SCL or L
Clay content - 18 to 27 percent
Thickness - 2 to 15 mm
Separation - 4 to 10 inches
E&Bt2 horizon
- E material (95 percent or more)
Value - 7 or 8 dry, 5 or 6 moist
Chroma - 3 or 4 dry or moist
Texture - LCOS or COS
Clay content - 5 to 12 percent
Rock fragments - 15 to 35 percent gravel
Reaction - slightly acid through slightly alkaline
- Bt material (lamellae)
Value - 6 or 7 dry, 4 or 5 moist
Texture - SL or SCL
Clay content - 12 to 22 percent
Thickness - 2 to 15 mm
Separation - 4 to 15 inches
COMPETING SERIES: These are the Bissell, Bjork, Cowiche, Dodes, Fernpoint, Indiano, Jerusalem, Madras, Margerum, Noslo, Orr, Pahrange, Quailridge (T), Quiero, Ralls, Shoebend, Simcoe, Springmeyer, Truax, Uhaldi and Wenatchee series. Bissell soils are micaceous throughout, do not have lamellae and are 24 to 50 inches deep to substrata that is commonly stratified.. Bjork, Dodes, Pahrange, Noslo, Shoebend, and Uhaldi soils are 20 to 40 inches deep to a paralithic contact. Cowiche soils have less than 5 percent rock fragments in the argillic horizon, have a 2Bk horizon with carbonate accumulation and do not have lamellae. Fernpoint soils have stratified extremely gravelly or extremely cobbly 2C horizons, secondary CaCO3 at 40 inches, and a mean annual soil temperature of 47 to 51 degrees. Indiano, Madras, Quiero and Simcoe soils are 20 to 40 inches deep to a lithic contact. Jerusalem soils do not have lamellae below the argillic horizon and have base saturation of 50 to 75 percent in some part. Margerum soils have pumice throughout the particle-size control section. Orr soils are slightly alkaline or moderately alkaline and do not have lamellae below the argillic horizon. Quailridge soils are less than 25 inches deep the base of the argillic horizon. Ralls soils are less than 25 inches deep to the base of the argillic horizon and have silt loam and clay loam textures with less than 45 percent sand in the particle-size control section. Springmeyer and Truax soils are dry for more than 145 days during summer and fall and do not have lamellae. In addition, Truax soils have Bq horizons. Wenatchee soils have less than 20 percent medium and coarse sand in the particle-size control section and do not have lamellae.
GEOGRAPHIC SETTING: Hullsgulch soils are moderately sloping to very steep hill backslopes, summits and shoulders and on landslides at elevations of 2,700 to 3,900 feet. Slopes range from 5 to 65 percent. These soils formed in granitic sediments deposited as basin-margin subaqueous deltas. The average annual precipitation is 12 to 17 inches. The average annual temperature is 48 to 52 degrees F. The frost-free period is 120 to 155 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cranegulch, Piercepark and Quailridge soils. Cranegulch soils have more than 35 percent clay in the particle-size control section. Piercepark soils have mollic epipedons 20 to 30 inches thick. Quailridge soils are less than 25 inches to the base of the argillic horizon. These soils occur on similar geomorphic positions as the Hullsgulch soils.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.
USE AND VEGETATION: These soils are used mainly for rangeland and commonly for homesites. Native vegetation is basin big sagebrush, antelope bitterbrush, bluebunch wheatgrass and Thurber needlegrass.
DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 10. Hullsgulch soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Boise County Area, Idaho, Parts of Ada and Boise Counties, 2005.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - zone from the surface to 12 inches (A and BA horizons)
Argillic horizon - zone from 12 to 38 inches (Bt1, Bt2 and Bt3 horizons)
Particle-size control section - zone from 12 to 32 inches
Soil moisture regime - aridic bordering on xeric
These soils are drier than other Xerolls in the region under similar precipitation due to early runoff and extended period of high evapotranspiration.