LOCATION NORWAT                  OR

Tentative Series
IRD. JRD/DAL/MPR
02/2025

NORWAT SERIES

Landscape--mountains
Landform--drainageways, swales, concave benches, complex landslides
Slope--5 to 15 percent
Parent material--thick mantle of volcanic ash over colluvium derived from andesite, basalt, or rhyolite
Mean annual precipitation--580 mm
Mean annual air temperature--6 degrees C
Depth class-deep and very deep
Drainage class-somewhat poorly drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--aquic

TAXONOMIC CLASS: Ashy over clayey, glassy over smectitic, frigid Aquic Vitrixerands

TYPICAL PEDON: Norwat ashy sandy loam - forest, on a 15 percent slightly concave slope. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 1 cm; slightly decomposed forest duff from Douglas-fir and grand fir

A1--1 cm to 13 cm; brown (10YR 5/3) ashy sandy loam, very dark brown (10YR 2/2) moist; weak thin and medium platy structure; soft, very friable, non-sticky and non-plastic; many very fine roots; many very fine and fine vesicular pores; 5 percent gravel and 5 percent cobbles; slightly acid (pH 6.2); abrupt smooth boundary. (2 to 6 inches thick)

A2--13 to 22 cm; brown (10YR 5/3) ashy loamy sand, very dark brown (10YR 2/2) moist; weak thick platy stucture parting to moderate fine subangular blocky; slightly hard, very friable, non-sticky and non-plastic; many very fine, fine and medium, and common very coarse roots; many very fine and fine interstitial pores; 5 percent gravel; slightly acid (pH 6.4); abrubt smooth boundary. (3 to 6 inches thick)

A3--22 to 43 cm; brown (10YR 5/3) ashy loamy sand, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky stucture; soft, very friable, non- sticky and non- plastic; many very fine to very coarse roots; common very fine to medium tubular pores; 5 percent gravel; neutral (pH 6.6); abrupt smooth boundary. (6 to 10 inches thick)

A4--43 to 66 cm; brown (10YR 5/3) cobbly ashy sandy loam, dark brown (10YR 3/3) moist; strong fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and non-plastic; many fine to medium roots; common very fine and fine irregular pores; 10 percent gravel, 23 percent cobbles; slightly acid (pH 6.2); clear wavy boundary. (8 to 10 inches thick)

2Bt--66 to 97 cm; yellowish brown (10YR 5/4) cobbly clay, dark brown (10YR 3/3) moist; strong fine and medium prismatic structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; few very fine continuous tubular pores; continuous thick clay films on ped faces and lining pores; 10 percent gravel, 10 percent cobble; moderately acid (pH 6.0). (10 to 14 inches thick)

2Btg--97 to 117 cm; light yellowish brown (10YR 6/4) cobbly clay, brown (10YR 4/3) moist; strong fine and medium prismatic structure; very hard, very firm, moderately sticky and moderately plastic; few very fine to fine roots; few very fine tubular pores; many moderately thick clay films on ped faces; many coarse distinct dark greenish gray (5GY 4/1) iron depletions on ped faces; common medium red (5R) redox concentrations on ped faces; 5 percent gravel and 15 percent cobbles, slightly acid (pH 6.2)

2R--117 cm (46 inches); basalt bedrock

TYPE LOCATION: Crook County, Oregon, in the Maury Mountains, Ochoco National Forest; on the 1700-400 road, about 1.0 kilometer from the junction with the 1700 road; SE1/4 of the NE1/4 of Section 3, T. 18 S., R 19 E.; Latitude 44.0395564, Longitude -120.4181623, WGS84 Datum (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean Annual Soil Temperature--5 to 7 degrees C
Soil Moisture--usually moist but dry for 45 to 60 consecutive days following the summer solstice
Thickness of mollic epipedon--50 to 70 cm
Thickness of argillic--20 to 70 cm
Depth to lithic contact--greater than 100 cm
Thickness of volcanic ash influenced layers--36 to 75 cm

Estimated properties of layers with andic soil properties
*0.2 to 2.0 mm fraction--60 to 80 percent of fine earth
*P Retention--25 to 40 percent
* Ammonium oxalate extractable Al + Fe --0.4 to 1.0 percent
*Volcanic glass content in 0.2 to 2.0 mm fraction--30 to 60 percent
*Water content at 1500kPa (air dry)--10 to 12 percent

Particle-size Control Section:
Upper part (ashy): 36 to 76 cm thick
*Clay content (weighted average)--7 to 18 percent
*Rock fragment content (weighted average)--5 to 15 percent
Lower part (clayey): 22 to 66 cm
*Clay content (weighted average)--35 to 60 percent
*Rock fragment content (weighted average)--5 to 35 percent

A1, A2, A3 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 loamy sand, ashy sandy loam
*Clay content--5 to 18 percent
*Sand content--55 to 90 percent
*Organic matter content--1 to 4 percent
*Total rock fragments--5 to 10 percent
*Gravel content-0 to 5 percent
*Cobble content--0 to 5 percent
*Stone content--0 to 5 percent
*Reaction-moderately acid to neutral (pH 5.8 to 6.6)
*Thickness--28 to 56 cm

A4 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-ashy loamy sand, ashy sandy loam
*Clay content--5 to 18 percent
*Sand content--55 to 90 percent
*Organic matter content--1 to 3 percent
*Total rock fragments--10 to 35 percent
*Gravel content-10 to 15 percent
*Cobble content--10 to 15 percent
*Stone content--0 to 5 percent
*Reaction-moderately acid to neutral (pH 5.8 to 6.6)
*Thickness--20 to 25 cm

2Btb horizons
*Hue--10YR or 7.5YR moist or dry
*Value--3 or 4 moist, 4 to 6 dry
*Chroma--2 to 6 moist or dry
*Fine earth texture--sandy clay, clay, clay loam
*Clay content--35 to 60 percent
*Sand content--25 to 65 percent
*Organic matter content--0.5 to 2 percent
*Total rock fragments-10 to 35 percent
*Gravel content--10 to 15 percent
*Cobble content--0 to 15 percent
*Stone content--0 to 2 percent
*Reaction-moderately acid to neutral (pH 5.8 to 6.6)
*Thickness--25 to 36 cm (10 to 14 inches)

COMPETING SERIES: None

GEOGRAPHIC SETTING:
Elevation--1220 to 1830 m
Climate-- cold, wet winters and warm, dry summers
Mean annual precipitation--480 to 660 mm
Mean annual temperature-4 to 7 degrees C
Frost-free period-- 45 to 60 days
Lithology-- basalts, rhyolites, pyroclastic tuffs and mesozoic marine sediments

GEOGRAPHICALLY ASSOCIATED SOILS:
Hafmau-occurs on rolling mountain sideslopes and benches; 25 to 50 cm to lithic contact
Maule-occurs on rolling plateau tops and mountain slopes; 50 to 100 cm to lithic contact, 18 to 36 cm of volcanic ash influence in upper part, 60 to 90 dry days following summer solstice
Normauk-occurs on relict landslides and mountain slopes; greater than 150 cm to restrictive layer, 36 to 50 cm of volcanic ash in uppert part, dry 45 to 60 days following summer solstice
Shotsprings-occurs on mountain sideslopes and ridges; 50 to 100 cm to lithic contact, 18 to 36 cm of volcanic ash influence in uppert part

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage-somewhat poorly drained
Saturation during normal years-Endosaturation from 50 to 100cm, April through June
Flooding--none
Ponding--none
Saturated hydraulic conductivity-high in upper part, moderately low to low in lower part

USE AND VEGETATION:
Use--timber production, domestic grazing, wildlife habitat and water supply
Potential native vegetation--Douglas-fir, grand fir, Ponderosa pine, Ross's sedge, pinegrass, Scoulers willow, chokecherry
Plant Association--CWG112, (Hall, 1973, Plant Communities of the Blue Mountains in Eastern Oregon and Southeastern Washington) and CWS0, grand fir with shrub dominated ground vegetation such as Scoulers willow, chokecherry, serviceberry and desert snowberry.
Plant Association Group--Douglas-fir moist and grand fir dry

DISTRIBUTION AND EXTENT: Central Oregon. MLRA 43C. Small extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED: Crook County, (Ochoco National Forest), Oregon; 2010

REMARKS:
Diagnostic horizons and features recognized in this pedon are
*Andic soil properties-1 to 66 cm
*Mollic epipedon-1 to 66 cm
*Argillic horizon-66 to 117 cm
*Particle-size control section-1 to 101 cm; 1 to 66 cm ashy; 66 to 101 cm clayey
*Redoximorphic features--97 to 117 cm (2Btbg)

Laboratory Data:. NSSL, Lincoln, NE; Grab Sample # S93-OR-013-006 Ochoco NF; composite sample from mineral soil surface to 66 cm (26 inches)

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National Cooperative Soil Survey
U.S.A.