LOCATION ZIONCREEK IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Vitrandic Hapludalfs
TYPICAL PEDON: Zioncreek ashy silt loam, cultivated; on a 3 percent slope at 2,160 feet elevation. When described on May 21, 1997, the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)
Ap1--0 to 5 inches; pale brown (10YR 6/3) ashy silt loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, and common medium roots; many very fine and common fine tubular pores; neutral (pH 7.0); gradual wavy boundary. (5 to 9 inches thick)
Ap2--5 to 9 inches; pale brown (10YR 6/3) ashy silt loam, brown (10YR 4/3) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, and few medium roots; many very fine, common fine and medium tubular pores; neutral (pH 7.0); clear wavy boundary. (0 to 5 inches thick)
Bt1--9 to 19 inches; mixed light yellowish brown (2.5Y 6/3) and very pale brown (10YR 7/3) silty clay loam, mixed olive brown (2.5Y 4/3) and brown (10YR 5/3) moist; weak medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine, few fine and medium roots; common very fine, few fine tubular pores; common distinct clay films on surfaces of peds and lining pores; common distinct silt coats on surfaces of peds; neutral (pH 7.2); gradual wavy boundary. (7 to 10 inches thick)
Bt2--19 to 27 inches; mixed pale brown (10YR 6/3) and light yellowish brown (2.5Y 6/3) silty clay loam, mixed brown (10YR 4/3) and olive brown (2.5Y 4/3) moist; weak coarse angular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine, few fine and medium roots; common very fine and few fine tubular pores; common distinct clay films on surfaces of peds and lining pores; common distinct silt coats on surfaces of peds; neutral (pH 7.2); clear wavy boundary. (6 to 8 inches thick)
Bk--27 to 34 inches; light gray (2.5Y 7/2) silty clay loam, grayish brown (2.5Y 5/2) moist; weak medium and coarse subangular blocky structure parting to weak fine and medium platy; slightly hard, friable, moderately sticky and moderately plastic; common very fine, few fine and medium roots; common very fine tubular pores; many medium and coarse lime seams and masses; violently effervescent (calcium carbonate); moderately alkaline (pH 8.0); clear wavy boundary. (7 to 13 inches thick)
C1--34 to 52 inches; pale yellow (2.5Y 7/3) stratified silt loam and silty clay loam, light olive brown (2.5Y 5/3) moist; weak medium and coarse platy structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine roots; common very fine tubular pores; strongly effervescent (calcium carbonate); moderately alkaline (pH 8.0); abrupt wavy boundary. (9 to 18 inches thick)
C2--52 to 60 inches; light gray (5Y 7/2) silty clay loam, olive gray (5Y 5/2) moist; strong medium and coarse platy structure; hard, firm, moderately sticky and moderately plastic; few very fine tubular pores; slightly effervescent (calcium carbonate); moderately alkaline (pH 8.0).
TYPE LOCATION: Boundary County, Idaho; about 5.5 miles southeast of Porthill; about 300 feet south and 1,700 feet west of the northeast corner sec. 36, T. 65 N., R. 1 W.
Latitude - 48 degrees, 57 minutes, 7 second North
Longitude - 116 degrees, 24 minutes, 1 second West
RANGE IN CHARACTERISTICS:
Moisture control section - dry 15 to 30 days (August to mid September), moist mid September through July; udic moisture regime
Average annual soil temperature - 43 to 46 degrees F.
Average summer soil temperature - 52 to 56 degrees F. with an O horizon
Depth to secondary calcium carbonates - 24 to 40 inches
Volcanic ash influence - 7 to 15 inches thick surface layers
Volcanic glass content - 5 to 20 percent
Acid-oxalate extractable Al + 1/2 Fe - 0.4 to 1.0 percent
Moist bulk density - 1.0 to 1.2 grams per cubic centimeter
Phosphate retention - 25 to 55 percent
Ap horizons:
Value - 6 or 7 dry, 4 or 5 moist
Clay content - 12 to 20 percent
Reaction - slightly acid or neutral
A horizon: present in undisturbed pedons
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 1 or 2 dry or moist
Clay content - 12 to 20 percent
Thickness - 1 or 2 inches
Reaction - slightly acid or neutral
BA horizon: present in some pedons
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Clay content - 12 to 20 percent
Reaction - slightly acid or neutral
Bt horizons:
Hue - 5Y, 2.5Y or 10YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Texture - SIL, SICL
Clay content - 18 to 34 percent
Lamellae - 1/16 to 1 inch thick present in some pedons
Reaction - slightly acid or neutral
Btk horizon: present in some pedons
Texture - SIL, SICL
Clay content - 18 to 34 percent
Calcium carbonate - lime in soft masses, seams and hard concretions
Bk horizon:
Hue - 2.5Y or 5Y
Value - 7 or 8 dry, 5 or 6 moist
Chroma - 2 or 3 dry or moist
Texture - SIL, SICL
Clay content - 18 to 34 percent
Effervescence (calcium carbonate) - strongly to violently effervescent
Calcium carbonate - lime in soft masses, seams and hard concretions
C horizons:
Hue - 2.5Y or 5Y
Chroma - 2 or 3 dry or moist
Texture - stratified SIL, SICL, VFSL
Clay content - 10 to 34 percent
Effervescence (calcium carbonate) - slightly to strongly effervescent
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Zioncreek soils are on terraces. Slopes range from 0 to 15 percent. These soils formed in glaciolacustrine sediments with minor amounts of volcanic ash mixed in the surface layers. Elevation ranges from 2,100 to 2,400 feet. The average annual precipitation is 25 to 32 inches and average annual air temperature is 42 to 45 degrees F. The average frost-free period is 100 to 135 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Artnoc, Caboose, Crash, Porthill, Rubson, and Wishbone soils. Artnoc, Caboose, Crash, and Wishbone soils are on terrace escarpments and contain less volcanic ash. Porthill soils are on terraces and have Bt horizons with more than 35 percent clay. Rubson soils are on terraces and do not have Bk horizons and are coarse-silty.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: Woodland, wildlife habitat, recreation, and dry-farm cropland. The principal crops are small grains, alfalfa hay, and pasture. Some areas are used for tree nurseries and homesites. Natural vegetation is mainly western hemlock, western redcedar, Douglas-fir, grand fir, and western larch, with an understory of longtube twinflower, queencup beadlily, starry false Solomons seal, darkwoods violet, bunchberry dogwood, baldhip rose, elk sedge, Oregon fairybells, pine reedgrass, and white spirea.
DISTRIBUTION AND EXTENT: Northern Idaho, and possibly northwestern Montana and northeastern Washington. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Boundary County, Idaho, 2002.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 9 inches (Ap1 and
Ap2 horizons)
Argillic horizon - the zone from 9 to 27 inches (Bt1 and Bt2 horizons)
Volcanic ash influence - the zone from 0 to 9 inches (Ap1 and Ap2 horizons)
Particle-size control section - the zone from 9 to 27 inches (Bt1 and Bt2 horizons)