LOCATION CROWFLATS NMEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, calcareous, thermic Ustic Torrifluvents
TYPICAL PEDON: Crowflats loam, rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 4 inches; pale brown (10YR 6/3) loam, dark grayish brown (10YR 4/2) moist; weak thick platy and weak coarse and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; common very fine tubular pores; strongly calcareous with disseminated lime; moderately alkaline (pH 8.2); abrupt smooth boundary. (2 to 6 inches thick)
C--4 to 48 inches; stratified pale brown (10YR 6/3) and brown (10YR 5/3) silt loam and very fine sandy loam, dark brown (10YR 3/3) and brown (10YR 4/3), moist; weak fine and medium subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many fine and very fine roots; common very fine tubular pores; strongly calcareous with lime disseminated; moderately alkaline (pH 8.3); clear smooth boundary. (40 to 60 inches thick)
TYPE LOCATION: Otero County, New Mexico; 1.9 miles southeast from Templeton ranch on dirt road to stock tank and corrals, then .5 mile southeast on same road to fence, then 1.45 miles north on dirt trail; SE1/4 sec. 19, T.22S., R.18E.
RANGE IN CHARACTERISTICS:
Soil moisture: intermittently moist in the soil moisture control section during July-August. The soil is moist for less than 90 cumulative days during the growing season in the control section. Ustic aridic soil moisture regime.
Clay content PSCS: 18 to 27 percent
The soil is stratified and has an irregular decrease in organic matter
Reaction: slightly or moderately alkaline.
A horizon
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3, dry or moist
Texture: silt loam, loam, very fine sandy loam
Structure: weak or moderate thin, medium or thick platy or weak or moderate coarse, medium or fine subangular blocky
Horizons with dark colors are too thin or too deeply buried to qualify as mollic epipedons
C horizon
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3, dry or moist
Texture: stratified silt loam and very fine sandy loam. Some pedons have 1 to 2 inch strata of loam, fine sandy loam, or silty clay loam
Structure: weak thin or medium platy, weak very fine, medium or coarse subangular blocky
COMPETING SERIES: These are the Nillo (TX) and Riveroad (AZ) series. Nillo soils have buried paleosols and formed in tuff parent material from the Duff and Pruett formations. Riveroad soils have clay loam textures in the control section and have mean annual precipitation of 12 to 16 inches.
GEOGRAPHIC SETTING: Crowflats soils are in basin floors that receive run-on water from adjacent landscapes. Slopes range from 0 to 2 percent. Elevations range from 3,500 to 4,500 feet. These soils formed in calcareous mixed alluvium. The climate is semiarid continental. Annual precipitation is estimated to be 8 to 10 inches with over 1/2 of the total falling in June through September. The mean annual air temperature is about 62 degrees to 66 degrees F., and the frost-free season is 200 to 220 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Holloman, Reeves, and Tome soils. Holloman and Reeves soils have gypsic mineralogy. Tome soils are dry in all parts of the moisture control section three-quarters or more of the time that the soil temperature at depth of 50 cm is 5 degrees C. or more.
DRAINAGE AND PERMEABILITY: Well-drained; slow runoff; moderate permeability. The soils are subject to flooding during high intensity summer thunderstorms.
USE AND VEGETATION: Principal use is livestock grazing. Native vegetation is giant sacaton, American tarbush, and creosotebush.
DISTRIBUTION AND EXTENT: South-central New Mexico. The series is inextensive. This soil occurs in LRR-D, MLRA 42.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Otero County (Otero Area), New Mexico, 1976.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 4 inches (A1 horizon)
Entisol feature - The absence of diagnostic subsurface horizons
Fluvial feature - Irregular decrease in organic carbon in the zone from 4 to 60 inches (C horizon)
Characterization data from Sample S74NM 35-6(1 to 12) support the classification. Field experience suggests that most Crowflats soils are fine-silty and behave like fine-silty soils.
Classified according to Soil Taxonomy Second Edition, 1999.
When the competing series section was updated in September 2001, questions were raised about the pedon description of this series. A field study of the type location is recommended to update the description.
Updated competing series section 4/10/2008, CEM