LOCATION PEYTON                  CO+MT WY

Established Series
Rev. GB/SJJ
04/2016

PEYTON SERIES


The Peyton series consists of very deep, well drained soils formed in thick alluvial fan materials derived from formations with arkosic properties. Peyton soils are on alluvial fans or valley side slopes. Slopes range from 0 to 15 percent. The mean annual precipitation is about 15 inches, and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aridic Argiustolls

TYPICAL PEDON: Peyton sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 5 inches; grayish brown (10YR 5/2) sandy loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure parting to moderate medium granular; soft, very friable; neutral (pH 6.6); clear smooth boundary. (4 to 8 inches thick)

A2--5 to 9 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine granular; slightly hard, very friable; neutral (pH 6.6); clear smooth boundary. (4 to 6 inches thick)

Bt1--9 to 13 inches; grayish brown (10YR 5/2) sandy clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure parting to moderate medium subangular blocks; extremely hard, very friable; clay films on faces of peds and in the inside of root channels; neutral (pH 6.6); clear smooth boundary. (0 to 6 inches thick)

Bt2--13 to 23 inches; brown (10YR 5/3) sandy clay loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocks; extremely hard, very friable; clay films on faces of peds; clay films filling in root channels and pores; neutral (pH 6.6); gradual smooth boundary. (4 to 8 inches thick)

BC--23 to 29 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; extremely hard, very friable; few thin discontinuous clay films on faces of peds and in root channels; neutral (pH 6.6); gradual smooth boundary. (4 to 8 inches thick)

C--29 to 50 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 5/3) moist; massive; extremely hard, very friable; neutral (pH 6.6).

TYPE LOCATION: Douglas County, Colorado, 150 feet west and 500 feet north of SE corner of Sec. 29, T. 10 S., R. 65 W.

RANGE IN CHARACTERISTICS: Mean annual soil temperature ranges from 42 to 46 degrees F., and mean summer soil temperature ranges from 60 to 68 degrees F. Depth to the base of the argillic horizon ranges from 18 to 40 inches. The mollic epipedon ranges from 8 to 16 inches thick. These soils are usually noncalcareous throughout and are always noncalcareous to depths of 40 inches or more. Organic carbon ranges from .8 to 2 percent in the mollic epipedon and decreases uniformly as depth increases, reaching levels of less than .2 percent within a depth of 50 inches. Rock fragments range from 0 to 15 percent but are usually less than 10 percent. They consist mainly of fine and very fine angular granite gravel. A large proportion of the sand fraction in these soils is medium and coarse angular granite sand. Packing patterns within the matrix tend to be cubical with a greater than normal number of flat bearing surfaces between sand grains. Horizons of low organic matter content have a greater than normal differential between dry and moist consistence and they are said to be "hard setting" when dry. Cumulative time the soil is moist in some part of the moisture control section and the soil temperature at a depth of 20 inches is 41 degrees F. or higher ranges approximately from 40 to 115 days.

The A horizon has hue of 5Y through 7.5YR, value of 4 to 5.5 dry, 2 to 3.5 moist, and chroma of 2 or 3. It usually has granular structure but has subangular blocky structure in some pedons. This horizon is soft to slightly hard. It is slightly acid to mildly alkaline (pH 6.1 to 7.8).

The Bt horizon has hue of 5Y through 7.5YR, value of 4 through 6 dry, 3 through 5 moist, and chroma of 2 through 6. It is typically sandy clay loam but clay ranges from 18 to 35 percent, silt from 5 to 30 percent, and sand from 40 to 75 percent with more than 35 percent being fine or coarser. This horizon usually has prismatic primary structure but has subangular blocky structure in some pedons. It is slightly acid to mildly alkaline (pH 6.1 to 7.8). Oriented clay films occur in some part of this horizon.

The C horizon has hue of 5Y through 7.5YR, value of 4 to 7 dry, and 3 to 6 moist. It is neutral or mildly alkaline (pH 6.6 to 7.8).

COMPETING SERIES: These are the Assinniboine (MT), Berlake (CO), Bostwick (CO), Cheesman (CO), Crittenden (MT), Duffson (CO), Eapa (SD), Emlin (CO), Evanot (CO), Evanston (CO), Jarre (CO), Joplin (MT), (T) Kenilworth (MT), Kevin (MT), Marmarth (ND), Morval (NM), Notter (UT), Nuley (MT), Perrypark (CO), Reicess (WY), Sugakool (WY), Telstead (MT), Turret (MT), Varney (MT), and Villa Grove (CO) series. Assinniboine, Evanston, Joplin, Kenilworth, Kevin, Telstead, and Villa Grove soils have continuous horizons of secondary calcium carbonate accumulation. Bostwick, Eapa, Emlin, Evanot, Morval, Notter, Nuley, Reicess, Sugakool, and Varney soils have consistent k horizons at some point above 40 inches. Crittenden soils have gravelly coarse sand 2C horizons. Berlake soils have moisture control sections that are dry in some parts for 15 consecutive days after July 1 and usually moist in some parts from August 15 to the winter solstice when the soil temperature at 20 inches is greater than 41 degrees F. Bostwick soils have argillic horizons with less than 35 percent fine or coarser sand. Cheesman, Duffson, and Marmarth soils have a lithic or paralithic contact at some point above a depth of 40 inches. Jarre and Turret soils have more than 15 percent rock fragments. Perrypark soils have lithochromic hue of 5YR or redder.

GEOGRAPHIC SETTING: Peyton soils are on upland ridges, alluvial fans, or valley side slopes. Slopes typically range from 0 to about 15 percent. The soils formed in thick alluvial fan materials derived from Dawson and Arapahoe formations or similar arkosic materials. At the type location the average annual precipitation is 13 to 18 inches with peak periods of precipitation in the spring and early summer. Mean annual temperature is 42 to 44 degrees F., and mean summer temperature is 58 to 66 degrees F. Elevation ranges from 5,600 to 8,000 feet. Frost-free period is 115 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Falcon and Pring soils. Falcon soils have bedrock at depths of less than 20 inches. Pring soils lack an argillic horizon.

DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.

USE AND VEGETATION: These soils are used as native pastureland or as dry or irrigated cropland. Native vegetation is bluestem, sandreed grass, blue grama, and needleandthread grass.

DISTRIBUTION AND EXTENT: East-central Colorado. The series is of moderate extent.

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

SERIES ESTABLISHED: Boulder Area, Colorado, 1971.

REMARKS: Diagnostic features include: a mollic epipedon from 0 to 13 inches; and an argillic horizon from 9 to 23 inches. Last updated by the state 6/91.



National Cooperative Soil Survey
U.S.A.