LOCATION HEECHEE NVEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Argixerolls
TYPICAL PEDON: Heechee cobbly loam, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 20 percent pebbles, 5 percent cobbles and 3 percent stones.
A1--0 to 4 inches; dark grayish brown (10YR 4/2) cobbly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, few fine and medium roots; many very fine and common fine continuous tubular pores; 10 percent pebbles, 5 percent cobbles, 3 percent stones; neutral (pH 7.2); clear smooth boundary. (2 to 5 inches thick)
A2--4 to 11 inches; dark grayish brown (10YR 4/2) cobbly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, few fine and medium roots; many very fine and common fine continuous tubular pores; 10 percent pebbles, 10 percent cobbles, 2 percent stones; neutral (pH 7.2); clear smooth boundary. (4 to 10 inches thick)
Bt1--11 to 18 inches; dark grayish brown (10YR 4/2) very cobbly clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium angular blocky structure; hard, firm, sticky and plastic; common very fine, few fine and medium roots; many very fine and few fine discontinuous tubular pores, common thin clay films on faces of ped and lining pores; 35 percent pebbles, 15 percent cobbles, 2 percent stones; neutral (pH 7.2); abrupt wavy boundary. (0 to 12 inches thick)
2Bt2--18 to 33 inches; brown (7.5YR 5/4) very gravelly sandy clay loam, dark brown (7.5YR 4/4) moist; moderate medium angular blocky structure; hard, friable, sticky and plastic; few very fine, fine and medium roots; many very fine and few fine discontinuous tubular pores; many thin clay films on faces of ped and lining pores; 40 percent pebbles, 15 percent cobbles, 2 percent stones; neutral (pH 7.2); clear wavy boundary. (10 to 18 inches thick)
2C--33 to 63 inches; strong brown (7.5YR 5/6) extremely cobbly sandy loam, strong brown (7.5YR 4/6) moist; massive; hard, very friable, slightly sticky and slightly plastic; few very fine, fine, medium and coarse roots; many very fine and few fine interstitial pores; 45 percent pebbles, 20 percent cobbles, 10 percent stones; neutral (pH 7.2).
TYPE LOCATION: Elko County, Nevada; about 18.5 miles southeast of Elko Nevada; approximately 1,585 feet south and 1,585 feet east of the northwest corner of section 33, T. 32 N., R. 57 E.; 40 degrees, 36 minutes, 58 seconds north latitude, 115 degrees, 33 minutes, 38 seconds west longitude.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist; moist in winter and spring, dry mid July through early October.
Soil temperature - 44 to 47 degrees F.
Mollic epipedon thickness - 12 to 20 inches, includes the upper part of the argillic horizon, and in some pedons the whole argillic horizon.
Depth to base of argillic horizon - 20 to 40 inches.
Reaction: Slightly acid or neutral.
Other features: In some small areas on plateaus, some pedons are recognized with a paralithic contact at 50 to 60 inches.
Control section - Clay content: 25 to 35 percent.
Rock fragments: 35 to 60 percent; 20 to 45 percent pebbles, 15 to 25 percent cobbles, 0 to 10 percent stones.
A horizon - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 1 through 3.
Bt horizon - Hue: 7.5YR or 10YR.
Value: 4 through 6 dry, 3 through 5 moist.
Chroma: 2 through 4.
Texture: Very cobbly clay loam, very gravelly sandy clay loam. or very cobbly loam.
Structure: Prismatic, angular block or subangular blocky.
C horizon - Hue: 7.5YR or 10 YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 4 through 6.
Texture: Extremely cobbly loam, extremely cobbly sandy loam; extremely cobbly coarse sandy loam and coarser textures are common in some pedons below 40 inches.
Rock fragments: 60 to 80 percent, mainly cobbles and stones.
Consistence: Soft to hard dry, nonsticky or slightly plastic or nonplastic or slightly plastic wet.
Structure: Subangular block or massive.
COMPETING SERIES: These are the Clanalpine (NV), Holmes (UT), Horrocks (UT), Hoskin (UT), Howcan, Pequop (NV), Squawtip (NV), Suak (NV), Valmar (ID), Vitale (ID) and Wambolt (T NV) series. Clanalpine and Squawtip have a paralithic contact at a depth of 20 to 40 inches. Holmes soils are dry for about 60 days and have C horizons within a depth of 16 to 32 inches that has textures of very gravelly and cobbly sand, loamy coarse sand, loamy sand or coarse sandy loam. Howcan soils have soil temperature of 37 to 44 degrees and the mollic epipedon does not include the upper part of the argillic horizons. Horrocks soils receive 18 to 24 inches of precipitation, are dry for 45 or more days, are 40 or more inches deep to bedrock and have soil temperatures of 38 to 45 degrees F. Hoskin, Suak, Valmar and Vitale soils are 20 to 40 inches deep to bedrock. Pequop soils are more than 40 inches deep to the base of the argillic horizons. Wambolt soils contain 60 to 80 percent rock fragments in the control section.
GEOGRAPHIC SETTING: Heechee soils are on fan piedmont remnants and in some areas on summits of plateaus. These soils formed in alluvium from granite, chert, quartzite, welded tuffs or rhyolite. Slopes are 2 to 30 percent. Elevations are 5,600 to 6,800 feet. The mean annual precipitation is about 12 to 16 inches; the mean annual temperature is about 42 to 45 degrees F.; and the frost-free season is about 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This the Stampede series. Stampede soils have an indurated duripan at a depth of 20 to 40 inches and have clay textured argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; slow and medium runoff; moderately slow over rapid permeability.
USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is mainly mountain big sagebrush, antelope bitterbrush, bluebunch wheatgrass, wyethia, downy rabbitbrush, and bottlebrush squirreltail.
DISTRIBUTION AND EXTENT: Northeast Nevada. MLRA 25. These soils are not extensive.
MLRA OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Elko County, Central part, Nevada. 1986.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 18 inches (A1, A2 and Bt2 horizons).
Argillic horizons - The zone from 11 to 33 inches (Bt1 and 2Bt2 horizons).
Particle-size control section - The zone from 11 to 31 inches (2Bt2 and part of the 2Bt2 horizons).
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.