LOCATION GRUNON                  WY

Tentative Series
ALB/DPG/DEW
05/2024

GRUNON SERIES


Depth class: Very shallow and shallow
Drainage class: Well drained
Saturated hydraulic conductivity class: Moderately high
Parent material: Slope alluvium over residuum weathered from interbedded sedimentary rock Geomorphic location: Structural benches and hillslopes
Slope range: 2 to 15 percent
Mean annual temperature: 4.5 degrees C (40 degrees F)
Mean annual precipitation: 205 millimeters (8 inches)

Taxonomic Class:
Loamy, mixed, superactive, frigid Lithic Ustic Haplocambids

Typical Pedon:
Grunon loam in rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 8 centimeters; very pale brown (10YR 7/3) loam, brown (10YR 4/3) moist; moderate very thick platy structure; slightly hard, friable, slightly sticky, slightly plastic; few very fine roots throughout; common very fine vesicular pores; slightly effervescent; 5 percent channers; strongly alkaline (pH 8.6); clear smooth boundary.

Bkn--8 to 17 centimeters; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine roots and fine roots throughout; many very fine and fine tubular pores; 5 percent calcium carbonate concretions on bottom of rock fragments; slightly effervescent; 5 percent channers; strongly alkaline (pH 8.8); gradual smooth boundary.

BCkn--17 to 30 centimeters; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine roots throughout; common very fine and fine tubular pores; 50 percent calcium carbonate concretions on bottom of rock fragments; 2 percent channers; slightly effervescent; strongly alkaline (pH 8.8); clear smooth boundary.

R--30 centimeters; bedrock.

Type Location:
Sweetwater County, WY
USGS Quadrangle: Austin Ranch NW
Latitude: 41.7115472
Longitude: -109.5716889
Datum: WGS84
Coordinates source: Hand-held GPS

Range in Characteristics:
Depth to cambic horizon--8 to 10 centimeters
Depth to lithic contact--30 to 44 centimeters
Particle-size control section (weighted averages):
Clay content--17 to 18 percent
Sand content--30 to 32 percent
Total rock fragments--0 to 4 percent

A horizon(s):
Hue--10YR or 2.5Y
Value--6 or 7 dry; 4 moist
Chroma--3 or 4 dry or moist
Texture (less than 2 mm fraction)--Loam or fine sandy loam
Clay content--10 to 24 percent
Rock fragments--2 to 33 percent; 0 to 10 percent channers, 0 to 20 percent gravels, 0 to 3 cobbles
Calcium carbonate equivalent--3 to 15 percent
Sodium absorption ratio--0 to 15
Reaction--pH 8.0 to 8.7
Thickness--8 to 10 centimeters

Bkn/Bk horizon(s):
Hue--10YR or 2.5Y
Value--5 or 6 dry; 4 moist
Chroma--3 or 4 dry or moist
Texture (less than 2 mm fraction)--Loam, sandy clay loam, or silt loam
Clay content--12 to 26 percent
Rock fragments--0 to 14 percent; 0 to 4 percent gravels, 0 to 10 percent channers, 0 to 40 percent parachanners, 0 to 55 percent paragravels
Calcium carbonate equivalent--3 to 5 percent
Sodium absorption ratio--0 to 15
Reaction--pH 8.0 to 9.0
Thickness--9 to 22 centimeters

BCkn/C horizon(s):
Hue--10YR or 2.5Y
Value--6 or 8 dry; 4 or 5 moist
Chroma--2 or 4 dry; 3 or 4 moist
Texture (less than 2 mm fraction)--Silt loam, silty clay loam, or loam
Clay content--15 to 28 percent
Rock fragments--0 to 25 percent; 0 to 60 percent paragravels, 0 to 10 percent paracobbles, 0 to 20 percent channers, 0 to 5 percent gravels
Calcium carbonate equivalent--3 to 15 percent
Sodium absorption ratio--13 to 25
Reaction--pH 8.5 to 9.4
Thickness--10 to 20 centimeters

Competing Series:
Pepton (WY) -- has 35 percent or more fine sand or coarser in the subsurface horizons

Geographic Settings:
Parent material--slope alluvium over residuum weathered from interbedded sedimentary rock
Landform--structural benches and hillslopes
Slope--2 to 15 percent
Mean annual air temperature--2.5 to 7 degrees C (37 to 45 degrees F)
Mean annual precipitation--180 to 230 mm (7 to 9 inches)
Frost-free period--50 to 100 days
Elevation--1,940 to 2,050 meters (6,360 to 6,730 feet)
Climate--long, cold winters; cool, moist springs; short, warm summers

Geographically Associated Soils:
None listed.

Drainage and Saturated Hydraulic Conductivity:
Drainage class: Well drained
Saturated Hydraulic Conductivity: 1.5 to 5 um/sec

Use and Vegetation:
Grunon soils are primarily used for rangeland. The potential native vegetation is Indian ricegrass, Wyoming big sagebrush, Gardener's saltbush, bottlebrush squirreltail, thickspike wheatgrass, bud sagebrush, bluebunch wheatgrass, and needle and thread.

Distribution and Extent:
Grunon soils are of small extent in southwestern Wyoming; MLRA 34A.

Soil Survey Region (SSR) Responsible:
Bozeman, Montana

Series Proposed:
Sweetwater County, WY 2022. Grunon series is a coined phrase.

Remarks:
Typical Pedon Taxonomic Features:
Ochric epipedon--0 to 8 centimeters (A horizon)
Cambic horizon--8 to 30 centimeters (Bkn and BCkn horizons)
Secondary calcium carbonate accumulation--8 to 30 centimeters (Bkn and BCkn horizons)
Depth to lithic contact--30 centimeters
Particle-size control section--0 to 30 centimeters
Taxonomic Version: Keys to Soil Taxonomy, 13th Edition, (2022)


National Cooperative Soil Survey
U.S.A.