LOCATION DAVTONE                 CO+UT WY

Established Series
Rev. LAN/DM/AP/JWB
12/2022

DAVTONE SERIES


The Davtone series consists of very deep, well drained soils that formed in alluvium and colluvium derived from red sandstone. Davtone soils are on mountains fans, drainageways, and hills. Slopes range from 2 to 45 percent. Mean annual precipitation is about 24 inches and the mean annual temperature is about 39 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive Pachic Argicryolls

TYPICAL PEDON: Davtone loam - rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 19 inches; very dark grayish brown (10YR 3/2) loam, very dark brown (10YR 2/2) moist; strong medium granular structure; slightly hard, friable, nonsticky and nonplastic; neutral (pH 6.8); clear smooth boundary. (6 to 20 inches thick)

AB--19 to 30 inches; reddish brown (5YR 4/3) sandy clay loam, dark reddish brown (5YR 3/3) moist; weak fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; 2 percent cobbles and 10 percent gravel; neutral (pH 7.0); clear wavy boundary. (0 to 11 inches thick)

Bt1--30 to 41 inches; reddish brown (5YR 5/3) cobbly sandy clay loam, reddish brown (5YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common faint clay films on faces of peds; 20 percent cobbles and 10 percent gravel; neutral (pH 7.0); clear wavy boundary. (9 to 14 inches thick)

Bt2--41 to 48 inches; reddish brown (5YR 5/3) gravelly sandy clay loam, reddish brown (5YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many faint clay films on faces of peds; 5 percent cobbles and 10 percent gravel; neutral (pH 7.2); clear wavy boundary. (7 to 14 inches thick)

C--48 to 60 inches; yellowish red (5YR 5/6) very gravelly sandy loam, yellowish red (5YR 4/6) moist; massive; soft, very friable, nonsticky and nonplastic; 15 percent cobbles and 35 percent gravel; neutral (pH 7.2).

TYPE LOCATION: Las Animas County, Colorado; about 4.3 miles west of Highway 12 in the south end of Duling Park; T. 33 S., R. 69 W.

RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is affected by precipitation that is relatively evenly distributed throughout the year with peak periods in spring and summer; Udic moisture regime bordering on ustic.
Mean annual soil temperature: 39 to 44 degrees F
Mean annual summer soil temperature: 55 to 59 degrees F
Depth to argillic horizon: 6 to 35 inches
Thickness of the mollic epipedon: 16 to 40 inches
Thickness of the argillic horizon: 16 to 28 inches
Particle-size control section (weighted average):
Clay content: 20 to 35 percent
Rock fragments: 0 to 35 percent gravel and cobbles

A horizon:
Hue: 7.5YR or 10YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 2 or 3
Reaction: neutral or slightly alkaline

Bt horizon:
Hue: 10R to 5YR
Value: 3 to 5 dry, 3 or 4 moist
Chroma: 2 or 3
Texture: loam, sandy clay loam, clay loam modified by 0 to 35 percent rock fragments.
Clay content: 20 to 35 percent
Rock fragments: 0 to 35 percent
Reaction: neutral or slightly alkaline

C horizon:
Hue: 10R to 5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 to 6
Texture: sandy loam, loam modified by 20 to 60 percent rock fragments
Clay content: 15 to 27 percent
Rock fragments: 20 to 60 percent dominantly gravel
Reaction: neutral or slightly alkaline

COMPETING SERIES: These are the Bachus, Bavdark (MT), Benteen (MT), Brushtop (ID), Clayburn (UT), Croydon (UT) Crystalbutte (ID), Dehana (ID), Decross (WY), Demast, Dranburn (ID), Dranyon (ID), Echemoor, Hagenbarth (ID), Hoopgobel (ID), Millerlake (WY), Odark, (MT), Pontuge (ID), Senchert (UT), Southmount (ID), Poodle (NV), Stubbs ((WY), Thulepah (NV), Vadnais (ID), and Winu (NV) series.
Bachus, Benteen, Hoopgobel, Senchert, Poodle, Stubbs, Vadnais, and Winu soils: are lithic or paralithic contact at depths of 20 to 40 inches.
Bavdark, Clayburn, Crystalbutte, Decross, Dranyon, Hagenbarth, and Millerlake: have hues of 7.5YR or yellower in the Bt horizon.
Brushtop and Echemoor soils: have paralithic contact at depths of 40 to 60 inches.
Croydon soils: have a lithic contact at depths of 40 to 60 inches.
Dehana soils: formed from rhyolitic, latite, and volcanic ash.
Demast soils: have lithic contact at a depth of 40 to 60 inches deep and formed from volcanic rock.
Dranburn and Pontuge soils have a xeric moisture regime.
Echemoor soils: have paralithic contact at a depth of 40 to 60 inches.
Odark and Southmount soils: have hues of 10YR or 2.5Y.
Thulepah soils: formed from basaltic rock.

GEOGRAPHIC SETTING:
Parent material: alluvium and colluvium derived from red sandstone
Landform: mountains, hills, drainageways and fans
Slopes: 2 to 45 percent
Elevation: 7,000 to 10,000 feet
Mean annual temperature: 36 to 42 degrees F
Mean annual precipitation: 20 to 26 inches
Frost-free period: 30 to 75 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hierro, Leadville, and Wichup series. The Hierro and Leadville soils lack a mollic epipedon, have an albic horizon, and have woodland vegetation. The Wichup soils have a layer of peat on the surface and have a water table within 2 feet of the surface.

DRAINAGE AND PERMEABILITY: Well drained, low to high runoff, moderate permeability.

USE AND VEGETATION: These soils are used for rangeland and wildlife habitat. Potential vegetation consists of Arizona fescue, Thurber's fescue, Parry oatgrass, mountain brome, western wheatgrass, and bluegrass.

DISTRIBUTION AND EXTENT: Colorado, Utah, and Wyoming; LRR E, MLRA 48A, 49, and 47; this series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Henry's Fork soil survey area, Utah and Wyoming, 1990.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: The zone from 0 to 30 inches. (A and AB horizons)
Argillic horizon: The zone from 30 to 48 inches. (Bt1 and Bt2 horizons)

The Davtone series was previously proposed in Routt County, Colorado and was later moved to Las Animas County, Colorado.
The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Classification was Fine-loamy, mixed Argic Pachic Cryoborolls (prior to Eighth Edition of the Keys)

Last updated 4/01.

Taxonomic Version: Eighth Edition, 1998


National Cooperative Soil Survey
U.S.A.