LOCATION PORKIES MIEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Fragic Haplorthods
TYPICAL PEDON: Porkies very gravelly silt loam on a northwest-facing 37 percent slope in a forested area at an elevation of about 450 meters. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 2 centimeters; slightly decomposed plant material; extremely acid; abrupt smooth boundary. (0 to 5 centimeters thick)
A--2 to 8 centimeters; dark reddish brown (5YR 3/2), very gravelly silt loam; moderate medium subangular blocky structure; friable; many fine to coarse roots and common very coarse roots; about 20 percent gravel, 5 percent cobbles, 5 percent channers, 5 percent flagstones, 5 percent stones and 5 percent boulders; extremely acid (pH 4.4); abrupt smooth boundary. (0 to 13 centimeters thick)
E--8 to 10 centimeters; reddish brown (5YR 4/3), very gravelly fine sandy loam, reddish gray (5YR 5/2), dry; moderate medium subangular blocky structure; friable; many fine to coarse roots; about 20 percent gravel, 5 percent cobbles, 5 percent channers, 5 percent flagstones, 5 percent stones and 5 percent boulders; very strongly acid (pH 4.9); clear broken boundary. (0 to 25 centimeters thick)
Bhs--10 to 18 centimeters; dark reddish brown (5YR 3/2), very gravelly fine sandy loam; moderate medium subangular blocky structure; friable; many fine to coarse roots; about 20 percent gravel, 5 percent cobbles, 5 percent channers, 5 percent flagstones, 5 percent stones and 5 percent boulders; strongly acid (pH 5.1); clear wavy boundary. (0 to 25 centimeters thick)
Bs1--18 to 79 centimeters; reddish brown (5YR 4/4), very gravelly sandy loam; moderate medium and coarse subangular blocky structure; friable; many fine to coarse roots; about 20 percent gravel, 5 percent cobbles, 5 percent channers, 5 percent flagstones, 5 percent stones and 5 percent boulders; strongly acid (pH 5.4); gradual wavy boundary.
Bs2--79 to 102 centimeters; reddish brown (5YR 4/4), very bouldery sandy loam; moderate medium and coarse subangular blocky structure; friable; many fine and medium roots; about 20 percent gravel, 2 percent channers, 20 percent stones and 15 percent boulders; moderately acid (pH 5.7); few 0.5 to 1.25 inch lenses of reddish brown (5YR 4/4) very fine sandy loamy and dark reddish brown (5YR 3/3) fine sandy loam; clear wavy boundary. (Combined thickness of the Bs horizons - 51 to 102 centimeters)
Bt--102 to 127 centimeters; reddish brown (5YR 4/4), very bouldery sandy loam; moderate fine and medium subangular blocky structure; friable; many fine and medium roots; many discontinuous faint reddish brown (5YR 4/4) clay films on all faces of peds; about 20 percent gravel, 2 percent channers, 20 percent stones and 15 percent boulders; moderately acid; clear wavy boundary. (0 to 51 centimeters thick)
Btx--127 to 155 centimeters; reddish brown (5YR 4/4), bouldery fine sandy loam; weak thick platy structure parting to moderate fine subangular blocky structure; firm, hard; common medium and coarse roots; common patchy faint reddish brown (5YR 4/4) clay films on all faces of peds; about 10 percent gravel, 5 percent cobbles, 2 percent channers, 2 percent flagstones, 2 percent stones and 10 percent boulders; strongly acid (pH 5.4); abrupt wavy boundary. (25 to 51 centimeters thick)
E/Bt--155 to 229 centimeters; dark reddish brown (2.5YR 3/4), extremely gravelly coarse sand (E) and red (2.5YR 4/6), extremely gravelly coarse sandy loam (Bt); single grain; loose; common fine and medium roots; common patchy faint clay bridging between sand grains; about 40 percent gravel, 10 percent cobbles, 10 percent stones and 5 percent boulders; slightly acid. (0 to 102 centimeters thick)
TYPE LOCATION: Major Land Resource Area (MLRA 93B) Superior Stony and Rocky Loamy Plains and Hills, Eastern Part; Ontonagon County Michigan Subset; about 1.3 miles east of the Gogebic County Line and 1.25 miles south of South Boundary Road; about 2400 feet east and 1000 feet north of the southwest corner of Section 29, T50N, R44W, USGS Tiebel Creek, MI, topographic quadrangle.; latitude 46 degrees 41 minutes 48 seconds North and longitude 89 degrees 50 minutes 5 seconds West.
RANGE IN CHARACTERISTICS:
Thickness of the genetic horizons (depth to the C horizon) - 152 to over 203 centimeters
Depth to fragic soil properties - 102 to 152 centimeters
Reaction - extremely acid to slightly acid (pH 3.5 to 6.5)
Rock fragment volume (above 100 centimeters) - 25 to 65 percent
Rock fragment volume (below 100 centimeters) - 35 to 80 percent
Rock fragment volume (particle-size control section) - above 35 percent
Soil horizons in the upper part of the profile are commonly mixed, buried or have broken horizon boundaries as a result of tree wind throw.
O horizon
Hue: 5YR or 7.5YR
Value: 2 to 2.5
Chroma: 0 to 2
A horizon
Hue: 5YR or 7.5YR
Value: 2.5 or 3
Chroma: 1 or 2
Texture: gravelly to extremely gravelly, cobbly or very cobbly analogs of silt loam, loam or fine sandy loam
E horizon
Hue: 5YR or 7.5YR
Value: 4 or 5
Chroma: 2 or 3
Texture: gravelly to extremely gravelly, cobbly or very cobbly analogs of loam, fine sandy loam, silt loam or sandy loam
Bw horizon (when present)
Hue: 5YR
Value: 3 or 4
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of fine sandy loam, sandy loam, silt loam or sand
Bhs horizon
Hue: 5YR or 7.5YR
Chroma: 2 or 3
Texture: gravelly to extremely gravelly, cobbly or very cobbly analogs of loam, fine sandy loam or sandy loam
Bs horizons
Hue: 5YR or 7.5YR
Value: 3 or 4
Chroma: 3 or 4
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of sandy loam or fine sandy loam
Bt horizon
Hue: 2.5YR or 5YR
Value: 3 or 4
Chroma: 3 or 4
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of sandy loam, fine sandy loam or silt loam
Btx and Bx horizons
Hue: 2.5YR to 7.5YR
Value: 2.5 to 5
Chroma: 2 to 6
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of fine sandy loam, loamy fine sand, or loam sand
E part of the E/Bt and Bt/E horizons
Hue: 5YR or 7.5YR
Value: 4 or 5
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of fine sandy loam, coarse sand or loamy coarse sand
Bt part of the E/Bt and Bt/E horizons
Hue: 2.5YR or 5YR
Value: 3 or 4
Chroma: 4 to 6
Texture: gravelly to extremely gravelly, cobbly to extremely cobbly, stony to extremely stony, bouldery or very bouldery analogs of fine sandy loam, coarse sandy loam or loam
C horizon (when present)
Hue: 5YR or 7.5YR
Value: 4 or 5
Chroma: 3 or 4
Texture: gravelly to extremely gravelly analogs of loamy sand, sandy loam, loamy fine sand or sand. Some pedons have pockets of gravelly to extremely gravelly analogs of silt loam or silty clay loam.
COMPETING SERIES: There are no other series in the same taxonomic family.
GEOGRAPHIC SETTING:
Parent material: loamy-skeletal till
Landforms: bedrock controlled ground moraines and end moraines
Slope: 35 to 70 percent
Elevation: 365 to 595 meters
Mean annual air temperature: 4 to 6 degrees C.
Mean annual precipitation: 760 to 860 millimeters
Frost-free period: 80 to 140 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Arcadian,
Flintsteel,
Gogebic,
Michigamme,
Oldman, and
Watton soils.
Arcadian - are on similar landform positions, but are 25 to 51 centimeters deep to bedrock, and in the Lithic Haplorthods Subgroup.
Flintsteel - are on lower elevations, are in the fine-loamy particle-size class, and in the Oxyaquic Glossudalfs Subgroup.
Gogebic - are on less sloping landform positions, have fragic soil properties with an upper boundary within 100 centimeters of the soil surface, are in the coarse-loamy particle-size class, and in the Oxyaquic Fragiorthods Subgroup.
Michigamme - are on similar landform positions, but are 51 to 102 centimeters deep to bedrock, and in the coarse-loamy particle-size class.
Oldman - are on less sloping landform positions, have fragic soil properties with an upper boundary within 100 centimeters of the soil surface, and are in the Alfic Oxyaquic Fragiorthods Subgroup.
Watton - are on lower elevations, are in the fine-loamy particle-size class, and in the Haplic Glossudalfs Subgroup.
Oldman soils form a drainage sequence (catena) with Porkies.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage water saturation does not occur above a depth of 203 centimeters year round (well drained). Additionally, a dry layer occurs from 20 to 40 centimeters deep in July and August.
Saturated hydraulic conductivity (A, E, Bhs, Bs, and Bt horizons) - moderate
Saturated hydraulic conductivity (Btx horizon) - very slow
Saturated hydraulic conductivity (E/Bt horizon) - moderate or moderately rapid
USE AND VEGETATION: Most areas are forested. Major species are sugar maple, basswood, yellow birch, eastern hemlock, ironwood, northern red oak, red maple and white pine. Quaking aspen, white birch and balsam fir may be found in areas that have been logged or burned. Understory vegetation includes spinulose shield fern, long beechfern, oak fern, blue cohosh, white baneberry, downy yellow violet, Canada white violet, sweet cicely, large-leaved aster, rosey twisted stalk, hairy solomon's seal, false solomon's seal and wild lily-of-the-valley.
DISTRIBUTION AND EXTENT:
Physiographic Division
--Laurentian Upland
Physiographic Province
--Superior Upland
Land Resource Region
--Northern Lake States Forest and Forage region (LRR K)
Major Land Resource Area
--Superior Stony and Rocky Loamy Plains and Hills, Eastern Part (MLRA 93B)
This series is of small extent; 3789 hectares are correlated.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Major Land Resource Area 93B Superior Stony and Rocky Loamy Plains and Hills, Eastern Part; Ontonagon County Michigan Subset, January 2007. Proposed in Ontonagon County, Michigan, 2003. Source of name is the local name for the Porcupine Mountains Wilderness State Park in Ontonagon County.
REMARKS: Diagnostic horizons and features recognized in the typical pedon are:
Ochric epipedon 0 to 10 centimeters (Oi, A, and E horizons)
Spodic horizon - 10 to 102 centimeters (Bhs, Bs1, and Bs2 horizons)
Argillic horizon - 102 to 155 centimeters (Bt and Btx horizons)
Fragic soil properties - 127 to 155 centimeters (Btx horizon)
Particle-size control section 27 to 100 centimeters
ADDITIONAL DATA: Refer to User Pedon ID S02MI-131-004 for Primary Characterization Data from National Soil Survey Laboratory (http://ssldata.nrcs.usda.gov/querypage.asp).