LOCATION FALCON CO+UT WYEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, frigid Lithic Haplustolls
TYPICAL PEDON: Falcon sandy loam - open timber. (Colors are for dry soil unless otherwise noted.)
Oi--1 inch to 0; pine needles and partly decomposed litter and twigs.
A--0 to 7 inches; dark grayish brown (10YR 4/2) sandy loam; very dark brown (10YR 2/2) moist; moderate fine granular structure; soft, very friable, 10 percent gravel; neutral; clear smooth boundary. (5 to 12 inches thick)
C--7 to 14 inches; light gray (10YR 7/2) gravelly sandy loam; grayish brown (10YR 5/2) moist; weak medium subangular blocky structure; very hard, very friable; 20 percent fine and very fine angular granite gravel; neutral; abrupt smooth boundary.
R--14 inches; hard arkosic sandstone and conglomerate.
TYPE LOCATION: Douglas County, Colorado; on the east side of Colorado State Highway 83, 500 feet north and 1,250 feet east of the southwest corner, Sec. 35, T. 10 S., R. 66 W.; Cherry Valley School USGS quad; Lat. 39 degrees 7 minutes 53 seconds N., Long. 104 degrees 45 minutes 1 second W., NAD 27
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 40 to 45 degrees F.
Mean summer soil temperature: 53 to 62 degrees F.
Mean winter soil temperature: warmer than 32 degrees F, and the soils are not continually frozen during the winter
Depth to lithic contact: 10 to 20 inches
Particle-size control section (weighted average):
Texture: Usually gravelly coarse sandy loam, fine sandy loam, or sandy loam
Clay content: 5 to 20 percent
Silt content: 5 to 35 percent
Sand content: 50 to 80 percent, with more than 35 percent being fine or coarser sand. A large proportion of the sand fraction is medium, coarse, and very coarse angular sand which has a high percentage of flat bearing surfaces between sand grains.
Rock fragments: 0 to 35 percent, mainly less than 3 inches in diameter but range from 1/8 to 10 inches in diameter.
A horizon:
Hue: 2.5Y to 7.5YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 1 to 4 dry or moist
Base saturation: typically is more than 80 percent but ranges from 60 to 100 percent
Reaction: moderately acid to slightly alkaline
C horizon (when present):
Hue: 2.5Y to 7.5YR
Value: 4 to 7 dry, and 4 or 5 moist
Chroma: 2 to 4 dry or moist
Texture: fine sandy loam or sandy loam.
Base saturation: typically is more than 80 percent but ranges from 60 to 100 percent
Reaction: moderately acid to moderately alkaline
COMPETING SERIES: These are the Akhoni (NM), Ansari (CO), Corpening (WY), and Falconry (CO) series. Akhoni soils do not have particle-size control sections dominated by coarse sand and have B horizons. Ansari and Corpening soils are calcareous and have continuous horizons of secondary calcium carbonate accumulation. Falconry soils have less than 35 percent fine sand and coarser.
GEOGRAPHIC SETTING: Falcon soils are on upland ridges, hills, sideslopes or mountain hillslopes, and benches generally at the crests and shoulders of the highest parts of the landscape. Slope gradients range from 0 to 65 percent. At the type location, the soils formed in materials weathered residually from arkose sedimentary beds overlying strata of hard sandstone and conglomerate. In other areas, the soils formed in interbedded sandstone and shale and siltstone. The mean annual precipitation in Colorado ranges from 16 to 19 inches. In Utah, and other areas in Colorado, precipitation ranges from 16 to 25 inches per year in elevations ranging from 7,400 to 9,500 feet with annual temperatures of 37 to 44 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kettle and Pring soils. Kettle soils have ochric epipedons and albic horizons. Pring soils do not have bedrock above depth of 40 inches.
DRAINAGE AND PERMEABILITY: Well to somewhat excessively drained; medium runoff; rapid to moderately rapid permeability above the bedrock.
USE AND VEGETATION: These soils are used primarily as native pastureland. In some localities they support stands of ponderosa pine of some importance for forestry. Native vegetation is primarily thin stands of ponderosa pine, Gambel oak, mountainmahogany, and grasses.
DISTRIBUTION AND EXTENT: The Black Forest areas of east-central Colorado and southwestern Colorado and the southeastern and central part of Utah. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Lakewood, Colorado
SERIES ESTABLISHED: Cherry Creek Soil Conservation District, El Paso and Douglas Counties, Colorado, 1946.
REMARKS: Diagnostic horizons and features in this pedon include:
Mollic epipedon: 0 to 7 inches
Lithic contact: 14 inches
Last updated by the state 2/99