LOCATION HANKINS OR
Established Series
Rev. ELD/AON/TDT
08/2025
HANKINS SERIES
Landscape--Blue and Ochoco mountains
Landform--mountain slopes, low hills, complex landslides
Slope--0 to 70 percent
Parent Material-- residuum and colluvium derived from tuff with an influence of volcanic ash in the surface
Mean annual precipitation--505mm
Mean annual air temperature--about 6 degrees C
Depth class--deep and very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine, smectitic, frigid Vertic Palexerolls
TYPICAL PEDON: Hankins cobbly ashy loam, woodland
Oi--0 to 3 cm; slightly decomposed needles and twigs.
A1--3 to 10 cm; cobbly ashy loam; gray (10YR 5/1) dry, very dark gray (10YR 3/1) moist; weak fine granular structure; soft, very friable, slightly sticky, slightly plastic; common very fine roots throughout; many very fine irregular pores; 5 percent gravels and 20 percent cobbles; neutral; clear smooth boundary.
A2--10 to 25 cm; cobbly ashy loam; gray (10YR 5/1) dry, very dark gray (10YR 3/1) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine roots throughout; many very fine tubular pores; 5 percent gravels and 20 percent cobbles; neutral; clear smooth boundary.
2BA--25 to 36 cm; cobbly clay loam; gray (10YR 5/1) dry, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; hard, firm, moderately sticky, moderately plastic; common fine roots throughout; many very fine tubular pores; 7 percent faint clay films on ped faces; 20 percent cobbles; neutral; clear smooth boundary.
2Bt1--36 to 58 cm; cobbly clay; brown (10YR 5/3) dry, dark brown (7.5YR 3/2), moist; moderate medium subangular blocky, and weak medium prismatic structure; very hard, very firm, very sticky, very plastic; few fine and medium roots throughout; common very fine tubular pores; 30 percent distinct clay films on ped faces; 30 percent cobbles; neutral; clear smooth boundary.
2Bt2--58 to 104 cm; cobbly clay; brown (7.5YR 5/3) dry, dark brown (7.5YR 3/3) moist; moderate medium subangular blocky structure; extremely hard, very firm, very sticky, very plastic; few fine and medium roots throughout; common very fine tubular pores; 40 percent prominent clay films on ped faces; 30 percent cobbles; neutral; clear smooth boundary.
2BC--104 to 117 cm; very cobbly clay; pale brown (10YR 6/3) dry, brown (10YR 4/3) moist; weak coarse subangular blocky structure; extremely hard, very firm, very sticky, very plastic; few fine roots throughout; few very fine tubular pores; 20 percent distinct clay films on ped faces; 40 percent cobbles; neutral; clear smooth boundary.
2Cr--117 cm; weathered tuff.
TYPE LOCATION: Jefferson County, Oregon; 18 km south of Ashwood; 60 m west of where the A-Y Road crosses Big Log Creek; 15 m south and 400 m east of NW corner of sec. 34, T. 11 S., R. 17 E.; Latitude 44.5770662, Longitude -120.6807925, WGS84; coordinates determined from PLSS description.
RANGE IN CHARACTERISTICS: Mean annual soil temperature--3 to 7 degrees C
Soil moisture--usually moist, dry for 60 to 90 days in summer and early fall
Mollic epipedon--50 to greater than 100 cm thick
Depth to paralithic contact--greater than 100 cm below the mineral soil surface
Reaction--neutral to slightly acid
Thickness of volcanic ash influenced layers--18 to 36 cm
Estimated properties of layers influenced by volcanic ash
Ammonium oxalate extractable Al + Fe--0.2 to 0.5 percent
0.02 to 2.0 mm fraction--greater than 30 percent
Volcanic glass in the 0.02 to 2.0 mm fraction--15 to 40 percent
Particle-size Control Section
Clay--35 to 60 percent
Total fragments--0 to 35 percent
Fragment types--andesitic tuff, rhyolite, basalt
A horizons
Hue--10YR moist or dry
Value--2 or 3 moist, 3 to 5 dry
Chroma--1 to 3 moist or dry
Fine earth texture--ashy sandy loam, ashy fine sandy loam, ashy loam
Clay--10 to 20 percent
Sand--45 to 80 percent
Organic matter--2 to 8 percent
Total fragments--0 to 30 percent
Gravel--0 to 30 percent
Cobbles--0 to 30 percent
Stones--0 to 10 percent
2BA horizon
Hue--10YR moist or dry
Value--2 or 3 moist, 3 to 5 dry
Chroma--1 to 3 moist or dry
Fine earth texture--clay loam, clay
Clay--30 to 50 percent
Sand--25 to 45 percent
Organic matter content--2 to 6 percent
Total fragments--0 to 30 percent
Gravel--0 to 30 percent
Cobbles--0 to 30 percent
Stones--0 to 10 percent
Thickness--0 to 20 cm (Not all pedons have a 2BA horizon)
2Bt1 horizon
Hue--10YR to 5YR moist or dry
Value--2 or 3 moist, 4 to 5 dry
Chroma--2 to 4 moist or dry
Fine earth texture--clay
Clay--40 to 60 percent
Sand--15 to 40 percent
Organic matter content--1 to 4 percent
Total fragments--0 to 30 percent
Gravel--0 to 30 percent
Cobbles--0 to 30 percent
Stones--0 to 10 percent
2Bt2 horizon
Hue--10YR to 5YR moist or dry
Value--3 or 4 moist, 4 to 6 dry
Chroma--2 to 4 moist or dry
Fine earth texture--clay
Clay--40 to 60 percent
Sand--15 to 40 percent
Organic matter content--0.5 to 2 percent
Total fragments--0 to 30 percent
Gravel--0 to 30 percent
Cobbles--0 to 30 percent
Stones--0 to 10 percent
2BC horizon
Hue--10YR to 5YR moist or dry
Value--3 or 4 moist, 4 to 6 dry
Chroma--2 to 4 moist or dry
Fine earth texture--clay, clay loam
Clay--35 to 60 percent
Sand--15 to 45 percent
Organic matter content--0.0 to 2 percent
Total fragments--0 to 40 percent
Gravel--0 to 30 percent
Cobbles--0 to 40 percent
Stones--0 to 10 percent
COMPETING SERIES:
Booth--lacks O horizon, mollic epipedon less than 50 cm thick, 50 to 100 cm to lithic contact
Campcreek--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
Carryback--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
Crowcamp-- lacks O horizon, lacks influence of volcanic ash in surface
Golars--50 to 100 cm to lithic contact
Jesh--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
Joenchris--lacks O horizon, mollic epipedon less than 50 cm thick, greater than 150 cm to restriction
Kidnapspring--greater than 150 cm to restriction, dry for 45-60 consecutive days
Lacrol--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
Longbarn--lacks O horizon, mollic epipedon less than 50 cm thick
Meaufun--contains fine ash in the surface with less than 45 percent sand
Peaviner--100 to 150 cm to lithic contact, dry for 45-60 consecutive days, minor influence of volcanic ash in surface
Tippett--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
Warpaint--lacks O horizon, greater than 150 cm to restriction
Zumwalt--lacks O horizon, mollic epipedon less than 50 cm thick, lacks influence of volcanic ash in surface
GEOGRAPHIC SETTING:
Elevation--760 to 1585 m
Climate--cold, moist winters and warm, dry summers
Mean annual precipitation--355 to 760 mm
Mean annual air temperature--3 to 7 degrees C
Frost-free period--50 to 100 days
Lithology--weathered volcanic tuff generally of the Clarno Formation
GEOGRAPHICALLY ASSOCIATED SOILS:
Ateron--occur on mountain slopes, low hills, and ridges; lack O horizon, 25 to 50 cm to lithic contact
Maucav--occur on mountain slopes, low hills, and plateau remnants; 50 to 100 cm to lithic bedrock
Yawkey--occur on mountain slopes; greater than 35 percent coarse fragments in the control section
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage--Well drained
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity--High in the upper ash influenced part, moderately low to low in the clayey lower part
USE AND VEGETATION:
Use--timber production, wildlife habitat, livestock grazing
Potential native vegetation--Ponderosa pine, Douglas-fir, common snowberry, elk sedge, Idaho fescue, antelope bitterbrush.
Typical plant associations-- CPS524 and CPG222; Johnson, C.G and Clausnitzer, R.R; 1992; Plant Associations of the Blue and Ochoco Mountains; USDA Forest Service; R6-ERW-TP-036-92. (Dry Ponderosa Pine Plant Association Group)
DISTRIBUTION AND EXTENT: Central Oregon, Southwestern Blue Mountains, MLRA 10. The soil is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Trout Creek-Shaniko Area, Oregon; 1970.
REMARKS:
Diagnostic horizons and other features recognized in this pedon are
Particle size control section--25 to 75 cm (2AB, 2Bt1, and part of the 2Bt2 horizon)
Mollic epipedon--3 to 104 cm (A1, A2, 2AB, 2Bt1, and 2Bt2 horizons)
Volcanic glass--3 to 25 cm (A1 and A2 horizons)
Argillic horizon--25 to 117 cm (2BA, 2Bt1, 2Bt2, and 2BC horizons)
Pale feature--abrupt textural change to 25cm with an absolute increase in clay content of 20 percent
Vertic subgroup--the calculated LE is over 6.0 centimeters within the upper 100 cm
Lithologic Discontinuity--25 cm
Paralithic contact--117 cm
In 2017, the type location was moved from Grant County back to the original 1970 type location within the Trout Creek-Shaniko soil survey area. This was done to preserve the original concept of coarse ash textures in the surface horizons.
National Cooperative Soil Survey
U.S.A.