LOCATION MAUCAV OR
Tentative Series
IRD. JRD/DAL
02/2025
MAUCAV SERIES
Landscape--mountains, plateaus
Landform--mountain slopes, lava plateaus, low hills, landslides
Slope--0 to 50 percent
Parent material--residuum and colluvium derived from basalt, andesite, or rhyolite with a minor influence of volcanic ash in the surface
Mean annual precipitation--about 460 mm
Mean annual air temperature--about 6 degrees C
Depth class--moderately deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
Soil moisture subclass--typic
TAXONOMIC CLASS: Fine, smectitic, frigid Ultic Argixerolls
TYPICAL PEDON: Maucav ashy sandy loam - upland forest, on a 5 percent slightly concave east-facing slope at 1525 meters elevation. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 3 centimeters; slightly decomposed needles and twigs
A--3 to 10 centimeters; dark brown (10YR 3/3) ashy sandy loam, very dark brown (10YR 2/2) moist; weak thick platy structure parting to weak fine subangular blocky; soft, friable, slightly sticky and slightly plastic; many very fine roots; many very fine and fine interstitial pores; 10 percent gravel; slightly acid (pH 6.2); abrupt smooth boundary. (5 to 13 centimeters thick)
2AB--10 to 23 centimeters; dark brown (10YR 3/3) clay loam, very dark brown (10YR 2/2) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; many fine and medium roots; common very fine and fine dendritic tubular pores; 10 percent gravel; slightly acid (pH 6.2); abrupt smooth boundary. (10 to 15 centimeters thick)
2Bt1--23 to 43 centimeters; dark brown (7.5YR 3/3) clay, dark brown (7.5YR 3/2) moist; moderate medium prismatic structure that parts to moderate fine prismatic; moderately hard, very firm, moderately sticky and very plastic; many fine, medium and coarse roots; few very fine dendritic tubular pores; 10 percent gravel; many thick dark brown (10YR 3/3) clay films on ped faces and lining pores; slightly acid (pH 6.2); abrupt smooth boundary. (15 to 25 centimeters thick)
2Bt2--43 to 69 centimeters; dark brown (7.5YR 3/2) gravelly clay, dark brown (7.5YR 3/2) moist; strong fine and medium prismatic structure; extremely hard, extremely firm, moderately sticky and very plastic; common fine and medium roots; few very fine dendritic tubular pores; 10 percent gravel, 5 percent cobbles; many thick dark brown (10YR 3/3) clay films on ped faces and in pores; slightly acid (pH 6.2); clear smooth boundary. (20 to 30 centimeters thick)
2R--69 centimeters; tuffaceous bedrock, silica coatings and dark manganese stains; very strongly coherent
TYPE LOCATION: Crook County, Oregon; Maury Mountains; Antelope Flat Campground; Sec. 24, T. 18 S., R. 19 E; Latitude 44.0015782, Longitude -120.3906465, WGS84 Datum (coordinates determined from PLSS description)
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--5 to 8 degrees C
Soil Moisture--usually moist, but dry 60 to 90 consecutive days following summer solstice in all parts between depths of 10 and 30 cm
Thickness of mollic epipedon--25 to 50 cm
Thickness of argillic horizon--36 to 76 cm
Depth to lithic contact--50 to 100cm
Reaction--slightly acid to neutral throughout
Ultic subgroup--base saturation (sum of cations) of 50 to 75 percent in Bt horizons
Thickness of volcanic ash influenced layers--3 to 18 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 content (weighted average): 35 to 60 percent
*Rock fragment content (weighted average): 5 to 20 percent
A horizon
*Hue--10YR
*Value--2 or 3 moist, 3 or 4 dry
*Chroma--2 or 3 moist or dry
*Fine earth texture--ashy sandy loam, ashy loam
*Clay--12 to 18 percent
*Sand--40 to 75 percent
*Organic matter--2 to 5 percent
*Total fragments--0 to 10 percent
*Gravel--0 to 10 percent
*Cobbles--0 to 5 percent
2AB horizon
*Hue--10YR
*Value--2 or 3 moist, 3 or 4 dry
*Chroma--2 or 3 moist or dry
*Fine earth texture--clay loam, sandy clay loam
*Clay--27 to 35 percent
*Sand--35 to 60 percent
*Organic matter--2 to 4 percent
*Total fragments--0 to 15 percent
*Gravel--0 to 10 percent
*Cobbles--0 to 5 percent
2Bt horizons
*Hue--10YR or 7.5YR
*Value--3 or 4 moist or 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--1.0 to 2.0 percent in upper part, 0.5 to 1 percent in lower part
*Total fragments--5 to 20 percent
*Gravel--0 to 10 percent
*Cobbles--0 to 10 percent
*Stones--0 to 5 percent
COMPETING SERIES:
Donner--50 to 100 cm to paralithic contact; does not contain surface with volcanic ash, does not have organic surface
Starhope--does not have volcanic ash surface layer, does not have organic surface
Uptmore--greater than 100 cm to lithic contact; does not have volcanic ash surface layer; 45 to 70 dry days following summer solstice
GEOGRAPHIC SETTING:
Elevation--1150 to 1800 meters
Climate--cool, moist winters and warm, dry summers
Mean annual precipitation--410 to 610 mm
Mean annual air temperature--4 to 7 degrees C
Frost-free period--50 to 80 days
GEOGRAPHICALLY ASSOCIATED SOILS:
Ateron--occurs on lava plateau tops, ridges, benches; 25 to 50 cm to lithic contact; averages greater than 35 percent fragments in particle size control section; lacks organic surface
Hankins--occurs on mountain slopes, ridges, and lava plateaus; greater than 150 cm to root restriction; greater than 18 cm of volcanic ash in surface
Maule--occurs on mountain slopes, plateaus; 50 to 100 cm to lithic contact; greater than 18 cm of volcanic ash in surface
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well
Saturation during normal years--none
Flooding--none
Ponding--none
Saturated hydraulic conductivity (Ksat)--high in surface, moderately low in subsurface
USE AND VEGETATION:
Use--timber production, grazing, wildlife habitat and water supply
Native vegetation: ponderosa pine, western juniper, mountain big sagebrush, bitterbrush, wild crabapple, Idaho fescue, bluebunch wheatgrass and western groundsel.
Plant Association--PIPO/ARTRV/FEID-AGSP, Ponderosa pine/mountain big sage/Idaho fescue-bluebunch wheatgrass, (CPS131)
Plant Association Group-- Dry Pine
DISTRIBUTION AND EXTENT: Central Oregon, Ochoco Mountains; MLRA 43C; This soil is of moderate extent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Crook County, Oregon; Ochoco National Forest; 2010
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
*Particle-size control section--10 to 60 cm; 2AB, 2Bt1, 2Bt2
*Mollic epipedon--3 to 43 cm; A, 2AB, 2Bt1
*Argillic horizon--10 to 69 cm; 2AB, 2Bt1, 2Bt2
*Volcanic ash--3 to 10 cm; A
*Ultic subgroup feature--23 to 69 cm; 2Bt1, 2Bt2
National Cooperative Soil Survey
U.S.A.