LOCATION MCHANDY IDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Chromic Haploxererts
TYPICAL PEDON: McHandy silty clay loam - rangeland at an elevation of 4,020 feet. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; pale brown (10YR 6/3) silty clay loam, dark brown (10YR 4/3) moist; moderate fine and medium granular structure; soft, very friable, sticky and plastic; common fine and very fine and few medium and coarse roots; many fine and very fine irregular and common fine and very fine tubular pores; common cracks 2.5 cm wide; neutral (pH 7.0); abrupt smooth boundary. (2 to 5 inches thick)
Bss1--2 to 19 inches; yellowish brown (10YR 5/4) silty clay loam, dark brown (10YR 4/3) 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 and fine tubular pores; common intersecting slickensides and pressure faces; common continuous cracks 1.0 to 2.5 cm wide are filled with material from A horizon; mildly alkaline (pH 7.5); clear smooth boundary. (0 to 25 inches thick)
Bss2--19 to 42 inches; yellowish brown (10YR 5/4) silty clay, dark yellowish brown (10YR 4/4) moist; strong medium and coarse prismatic structure; very hard, very firm, very sticky and very plastic; common fine and very fine roots along faces of peds; few fine and very fine tubular pores; common distinct intersecting slickensides and pressure faces; common continuous cracks 1.0 to 1.5 cm wide; 3 percent gravel; mildly alkaline (pH 7.6); gradual wavy boundary. (12 to 35 inches thick)
Bssk--42 to 53 inches; yellowish brown (10YR 5/4) silty clay, dark yellowish brown (10YR 4/6) moist; very pale brown (10YR 7/3) and brown (10YR 5/3) moist, calcium carbonate veins; moderate medium and coarse prismatic structure; very hard, firm, very sticky and very plastic; few very fine, fine, medium and coarse roots in cracks; few fine and very fine tubular pores; few distinct nonintersecting slickensides and pressure faces; 2 percent gravel; mildly alkaline (pH 7.6); slightly effervescent near gravel; clear wavy boundary. (0 to 7 inches thick)
Bkqm--53 to 60 inches; pink (7.5YR 7/4) strongly cemented duripan, strong brown (7.5YR 4/6) moist; massive; few fine and very fine roots matted at the top of the horizon; 20 percent gravel, 25 percent cobbles, 10 percent stones; strongly effervescent.
TYPE LOCATION: Gooding County, Idaho; about 10 miles north and 3 miles west of Bliss; about 2,250 feet north and 300 feet west of the southeast corner of Sec. 16, T5S, R12E. Lat. 43 degrees north, 4 minutes, 18 seconds; Long. 115 degrees west, 2 minutes, 4 seconds.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 50 to 53 degrees F.
Depth to bedrock - more than 60 inches
Clay (control section average) - 35 to 60 percent
Depth to duripan - 40 to 60 inches
Few to common intersecting slickensides in Bss horizons
Cracks - open July through October; closed during winter; 1 to 3 cm wide at a depth of 50 to 120 cm and extending upwards to the surface
Absent in some pedons - Bssk horizon
Present in some pedons - Bk, Bkq, Bssq, and Bsskq horizons
A horizon
Value - 4 to 6 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Bss and Bssk horizons
Hue - 10YR or 7.5YR
Value - 4 through 7 dry, 3 through 6 moist
Chroma - 3 through 6 dry or moist
Texture - SIC, SICL, C
Clay content - 35 to 60 percent
Calcium carbonate equivalent - 0 to 10 percent
Reaction - neutral to mildly alkaline
Rock fragments - 0 to 10 percent gravel, 0 to 5 percent cobbles Intersecting slickensides - few to common
Bkqm horizon
Strongly cemented duripan
Calcium carbonate equivalent - 0 to 10 percent
COMPETING SERIES: This is the Thorncreek (T) series. Thorncreek soils lack a duripan.
GEOGRAPHIC SETTING: McHandy soils are on basalt plateaus, mesas and escarpments. McHandy soils formed in weathered loess and silty alluvium. Slopes are 1 to 30 percent. Elevations range from 3,600 to 4,400 feet. The average annual precipitation is 9 to 11 inches. The average annual air temperature is 48 to 51 degrees F. and the frost free period is 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: On plateaus, McHandy soils occur with the following soils: Catchell soils, on ridges; Chilcott and Thorncreek soils, in concave positions; and Power soils, on mounds. Chilcott, Catchell and Power soils have argillic horizons and lack vertic properties. Thorncreek soils are deep to bedrock and have less well developed vertic properties. On escarpments, McHandy soils are on footslopes and Hobby soils are on middle and upper sideslopes. Hobby soils are moderately deep to bedrock, have mollic epipedons and have less well developed vertic properties than McHandy soils.
DRAINAGE AND PERMEABILITY: Well drained; runoff is rapid; permeability is very slow.
USE AND VEGETATION: McHandy soils are used for rangeland. Potential native vegetation is Wyoming sagebrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: McHandy soils are of small extent in south central Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Gooding County, Idaho, 1993.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 2 inches (A horizon)
Cambic horizon - the zone from 2 to 42 inches (Bss1 and Bss2 horizons)
Intersecting slickensides - few to common (Bss horizons)
Cracks- open July through October; closed during winter and early spring; 1 to 3 cm wide at a depth of 50 to 120 cm and extending upwards to the surface
Particle-size control section - zone from 10 inches to 40 inches (part of the Bss1 and part of the Bss2 horizons)