LOCATION MILEHIGH CO

Established Series
PRR-KLS-EED
03/2026

MILEHIGH SERIES

Depth class: Very deep
Drainage class: Well drained
Saturated hydraulic conductivity: Moderately high (0.4 to 3.6 cm/hr)
Parent material: Thick coarse-loamy human-transported material over mixed Holocene-aged alluvium
Geomorphic location: Fills and other leveled areas on stream terraces and plains
Slope range: 0 to 15 percent
Mean annual temperature: 11 degrees C
Mean annual precipitation: 405 millimeters

TAXONOMIC CLASS: Coarse-loamy, spolic, mixed, superactive, nonacid, mesic Anthroportic Ustorthents

TYPICAL PEDON: Milehigh sandy loam, 1 percent slope on a filled stream terrace under cultivated grass in a park, at an elevation of 1,579 meters. (Colors are for dry soil unless otherwise noted.)

^A--0 to 4 centimeters; very dark grayish brown (10YR 3/2); sandy loam, black (7.5YR 2.5/1) moist; weak fine granular structure; soft, very friable, non-sticky, non-plastic; many very fine and common fine roots throughout; noneffervescent; neutral (pH 7.0); abrupt smooth boundary (5 to 25 centimeters thick)

^C--4 to 15 centimeters; brown (10YR 4/3) sandy loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, slightly sticky, non-plastic; few very fine and very few fine roots throughout; 4 percent gravel; noneffervescent; neutral (pH 7.2); clear smooth boundary

^Cu1--15 to 31 centimeters; brown (10YR 4/3) gravelly artifactual sandy loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, non-sticky, non-plastic; very few fine roots; 10 percent gravel, 10 percent gravel-sized artifacts of asphalt; noneffervescent; neutral (pH 7.2); clear smooth boundary

^Cu2--31 to 57 centimeters; brown (10YR 4/3), sandy loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, friable, non-sticky, non-plastic; few fine roots throughout; 5 percent gravel, 5 percent gravel-sized artifacts of asphalt; noneffervescent; neutral (pH 7.2); clear smooth boundary

^C'1--57 to 76 centimeters; brown (10YR 4/3), sandy loam, dark brown (10YR 3/3) moist; massive; slightly hard, friable, non-sticky, non-plastic; 2 percent subangular and subrounded fine gravel; noneffervescent; neutral (pH 7.2); gradual smooth boundary

^C'2--76 to 112 centimeters; yellowish brown (10YR 5/4), sandy loam, brown (10YR 4/3) moist; massive; slightly hard, friable, non-sticky, non-plastic; 2 percent gravel, noneffervescent; neutral (pH 7.2); clear smooth boundary (Combined thickness of ^C horizons are 35 centimeters or more)

2C--112 to 200 centimeters; yellowish brown (10YR5/6), loamy sand, dark yellowish brown (10YR 4/4) moist; single grain; loose, non-sticky, non-plastic; noneffervescent; slightly alkaline (pH 7.4)

TYPE LOCATION:
Denver County, Colorado; located in the south-central part of Granado Park

USGS Quadrangle: Commerce City, CO
Latitude: 39.7894333
Longitude: -104.9495583
Datum: WGS84
Coordinates sources: Hand-held GPS

RANGE IN CHARACTERISTICS:
Depth to secondary carbonates--more than 100 centimeters
Thickness of human-transported material: greater than 75 centimeters Depth to seasonal high water table: Greater than 150 centimeters
Soil reaction: Neutral to slightly alkaline (pH 6.6 to 7.8)
Particle-size control section (weighted average):
Clay content--5 to 18 percent
Sand content--40 to 75 percent
Rock fragment content--0 to 15 percent
Artifact content--Less than 10 percent, by volume, some individual horizons have more than 10 percent artifacts

^A horizons:
Hue--7.5YR or 10YR
Value--2 to 4 dry; 2 or 3 moist
Chroma--2 to 4 dry; 1 to 3 moist
Texture (less than 2 mm fraction)--clay loam, loam, sandy loam
Clay content--1 to 18 percent, some individual horizons have up to 30 percent
Rock fragments--0 to 10 percent gravels
Artifacts--0 to 15 percent
Reaction--Neutral to slightly alkaline (pH 6.8 to 7.6)

^C(u) and ^C'(u) horizons
Hue--7.5YR
Value--3 to 6 dry; 1 to 5
Chroma--2 to 5 dry or
Texture (less than 2 mm fraction)--fine sandy loam, loamy coarse sand, loamy sand, sandy clay loam
Clay content--5 to 35
Rock fragments--0 to 25
Artifacts--0 to 15 percent
Reaction--Neutral to moderately alkaline (pH 7.0 to 8.2)

2Bwb and/or 2BCb horizons (when present):
Hue--2.5Y or 10YR
Value--3 to 5 dry; 2 to 4 moist
Chroma--3 or 5 dry or moist
Texture (less than 2 mm fraction)--sandy clay loam, sandy loam
Clay content--8 to 27 percent
Rock fragments--0 to 5 percent gravel
Reaction--Neutral to slightly alkaline (pH 7.0 to 7.8)
Thickness--0 to 70 centimeters

2C horizons
Value--4 to 6 dry; 3 to 5
Chroma--4 or 5 dry; 3 to 5
Texture (less than 2 mm fraction)-- coarse sand, fine sandy loam, loamy fine sand, loamy sand, sand, sandy clay loam, s
Clay content--2 to 28
Rock fragment content--0 to 15
Reaction--Slightly to moderately alkaline (pH 7.4 to 8.0
Thickness--0 to 90 centimeters

COMPETING SERIES:
These are the Greenvalley soils which formed in greater than 50 centimeters of coarse-loamy human-transported material over eolian sediments derived from glaciofluvial sources and may have buried argillic horizons.

GEOGRAPHIC SETTING:
Parent material: Thick coarse-loamy human-transported material over Holocene-aged alluvium
Landform: Fills and other leveled areas on stream terraces and plains
Slope ranges: 0 to 15 percent
Elevation: 1,565 to 1,690 meters
Frost-free period: 135 to 165 days
Mean annual air temperature: 10 to 12 degrees C
Mean annual precipitation range: 355 to 430 millimeters
Climate: Cold, dry winters and hot summers with North American monsoon precipitation from July through August. The driest months are December through February.

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Altitude, Elyria, and Vona soils.

Altitude soils are found on stream terraces, have a loamy-skeletal particle size control section, and form in human-transported materials over alluvium
Elyria soils are found on adjacent plains and strath terraces, have a fine-loamy particle size control section and form in human-transported materials over mixed eolian deposits or alluvium.
Vona soils are found on nearby stabilized dunes, have argillic horizons, and form in eolian sands.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Well drained
Saturated hydraulic conductivity: Moderately high (0.4 to 3.6 cm/sec)
Flooding: None
Ponding: None

USE AND VEGETATION:
Most areas are primarily used for urban development. Vegetation may include a mix of managed and unmanaged plant communities with a variety of native and non-native species. Many areas are vegetated with non-native ornamental landscaping and/or turfgrass associated with developed land uses. Some areas may exhibit weedy, invasive, and/or primary succession vegetation communities (e.g., abandoned lots and other unmanaged areas). The potential native vegetation is western sandcherry, leadplant, sand bluestem, and prairie sandreed.

DISTRIBUTION AND EXTENT:
Urban and other areas with human-modified landscapes on stream terraces along the South Platte River and in the vicinity of Denver in north-central Colorado. MLRA 67B - Central High Plains, Southern Part. These soils are of small extent.

SOIL SURVEY REGION (SSR) RESPONSIBLE: Raleigh, North Carolina (Special Projects Office)

SERIES ESTABLISHED: Denver County, Colorado 2025.

REMARKS:
Typical Pedon Taxonomic Features:
Ochric epipedon--The zone from 0 to 4 centimeters (^A horizon)
Human-transported materials--The zone from 0 to 112 centimeters (^A, ^C, ^Cu, ^C' horizons)
Human artifacts--The zone from 15 to 57 centimeters (^Cu horizons)
Lithologic discontinuity (buried soil)--At a depth of 112 centimeters
Particle-size control section--The zone from 25 to 100 centimeters
Taxonomic version: Keys to Soil Taxonomy, 13th edition, (2022)
Other: Milehigh name is a coined name based on Denver, Colorado's mile-high altitude.

ADDITIONAL DATA:
NASIS User Pedon ID: 2020CO031222

National Cooperative Soil Survey
U.S.A.