LOCATION PARKALLEY IDTentative Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Pachic Argicryolls
TYPICAL PEDON: Parkalley gravelly loam - on a slope of 20 percent under shrubs and grass at an elevation of 6,440 feet. (When described on August 4, 1982 the soil was dry throughout. Colors are for dry soil unless otherwise noted.)
A1--0 to 4 inches; dark brown (10YR 3/3) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure parting to strong fine granular; slightly hard, friable, slightly plastic; common very fine and fine, few medium and coarse roots; common very fine tubular and interstitial pores; 20 percent angular gravel; neutral (pH 7.2); clear smooth boundary. (3 or 4 inches thick)
A2--4 to 9 inches; dark brown (10YR 3/3) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium and coarse roots; common very fine tubular pores; 25 percent angular gravel; neutral (pH 7.2); clear smooth boundary. (5 to 18 inches thick)
A3--9 to 19 inches; brown (10YR 4/3) gravelly loam, very dark grayish brown (10YR 3/2) moist, moderate medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic, common very fine and fine, few medium and coarse roots; common very fine tubular pores; 30 percent angular gravel; neutral (pH 7.0); clear wavy boundary. (8 to 12 inches thick)
Bt--19 to 28 inches; brown (10YR 5/3) very flaggy clay loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; hard, friable, sticky and plastic; few very fine, fine, medium and coarse roots; common very fine tubular pores; few thin clay films on faces of peds and in pores; 25 percent angular gravel and 30 percent flags; neutral (pH 7.0); clear wavy boundary. (6 to 25 inches thick)
BC--28 to 41 inches; pale brown (10YR 6/3) extremely flaggy loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and plastic; few very fine, fine, medium, and coarse roots; few very fine tubular pores; neutral (pH 7.0); clear wavy boundary. (10 to 15 inches thick)
C--41 to 62 inches; light gray (10YR 7/2) extremely flaggy loam, grayish brown (10YR 5/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; few very fine interstitial pores; 25 percent angular gravel and 60 percent flags; neutral (pH 7.0).
TYPE LOCATION: Clark County, Idaho; about 6 miles west and 1 mile south of Kilgore; 1000 feet west and 2035 feet north of the southeast corner of section 8, T. 12 N., R. 38 E.
RANGE IN CHARACTERISTICS:
Average annual temperature - 37 to 43 degrees F.
Average summer soil temperature - 55 to 58 degrees F.
Average clay in control section - 24 to 34 percent
Average rock fragments in control section - 35 to 70 percent Flagstone immediately below the Argillic (above 40 inches) - 35 to 60 percent
Thickness of mollic epipedon - 16 to 30 inches
Depth to base of the Argillic - 28 to 35 inches
A horizons
Value - 3 or 4 dry, 2 or 3 moist
Chroma - 1 through 3
Reaction - slightly acid to mildly alkaline
Bt horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 or 3
Textures - FLX-CL, FLV-CL, GRV-L, GRV-CL, FLX-L
Sand content - 25 to 45 percent
Reaction - neutral through mildly alkaline
BC horizon
Rock fragments - 65 to 90 percent
COMPETING SERIES: These are the Bickmore, Bluebell, Geemore (T), Keman (T), Kiote, Nulligam, Panin, Parkay, Rutherford (T), Tusel, Woodcock, and Woodhurst series. The Bickmore, Bluebell, Panin, Rutherford (T), and Woodhurst soils are moderately deep to bedrock. Geemore soils have discontinuous silica cementation at depths of 40 inches or less. Keman soils are moderately and strongly acid and average less than 24 percent clay in the control section. Kiote soils receive less than 16 inches precipitation and are dry in all parts of the moisture control section for more than 45 consecutive days between July and October. Nulligam and Tusel soils are deeper than 35 inches to the bare of the Argillic. Parkay soils have A horizons less than 16 inches thick and lack Flagstone in or immediately below the Argillic. Woodcock soils are slightly acid in the Bt2 and have nondispersible clay nodules in the profile.
GEOGRAPHIC SETTING: Parkalley soils are on mountain sides and foothills at elevations of 6,000 to 7,500 feet. Slopes range from 1 to 50 percent. Average annual precipitation is 16 to 22 inches. Major precipitation is in the form of snow with significant amounts coming as summer rain storms. The average annual temperature is 37 to 43 degrees F., and the frost-free season is 40 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ezbin (T), Hagenbarth (T), Latigo (T), and Zeebar (T) soils. The Ezbin, Latigo, and Zeebar soils are not Pachic. Ezbin soils have O horizons under Douglas-Fir on mountain sides. Hagenbarth soils have less than 35 percent rock fragments in the control section and are on alluvial terraces. Latigo soils are on nearly level to steep rhyolite plains. Zeebar soils are on foothills and steeper mountains.
DRAINAGE AND PERMEABILITY: Well drained, slow to rapid runoff, moderately slow permeability.
USE AND VEGETATION: Parkalley soils are used for rangeland. Vegetation is mainly mountain big sagebrush, Idaho fescue, lupine, bluebunch wheatgrass, mountain snowberry, serviceberry, and ceanothus.
DISTRIBUTION AND EXTENT: Parkalley soils are of small extent in southeast Idaho.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Clark County, Idaho, 1984.
REMARKS: Diagnostic properties include: 35 percent or more gravel and flags in the series control section; an argillic horizon; 16 inches or more of mollic colors; cryic temperature regime; 60 inches or more in depth.