LOCATION PURCELLA NM+COEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Aridic Argiustolls
TYPICAL PEDON: Purcella loam in pinyon-juniper savannah. (Colors are for dry soil unless otherwise noted.)
A--0 to 12 inches; brown (7.5YR 4/2) loam, dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; slightly alkaline (pH 7.8) abrupt wavy boundary. (7 to 14 inches thick)
Bt1--12 to 22 inches; brown (7.5YR 5/4) cobbly loam, brown (7.5YR 4/2) moist; moderate coarse prismatic structure; hard, friable, slightly sticky and nonplastic; common very fine roots; few faint clay films on faces of peds; 5 percent gravel and 25 percent cobbles; slightly alkaline (pH 7.4); clear smooth boundary. (6 to 12 inches thick)
Bt2--22 to 43 inches; brown (7.5YR 5/4) extremely cobbly clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure; very hard, friable, moderately sticky and slightly plastic; few very fine roots; many distinct clay films on faces of peds; 30 percent gravel and 35 percent cobbles; slightly alkaline (pH 7.7); clear wavy boundary. (12 to 35 inches thick)
Bk--43 to 60 inches; pink (7.5YR 8/4) extremely cobbly clay loam, pink (7.5YR 7/4) moist; massive; slightly hard, very friable, moderately sticky and slightly plastic; 25 percent gravel and 40 percent cobbles; violently effervescent; calcium carbonate coatings on rock fragments and many secondary carbonate accumulations; slightly alkaline (pH 7.8).
TYPE LOCATION: Lincoln County, New Mexico; about 6 miles east of Encinoso; located in the northwest 1/4 of the northwest 1/4 of sec. 28, T. 7 S., R. 16 E.
RANGE IN CHARACTERISTICS:
Soil moisture regime: Aridic ustic moisture regime.
Soil temperature regime: mesic
Mean annual soil temperature: 50 to 54 degrees F
Particle-size control section: 18 to 35 percent clay and less than 45 percent sand
Depth to the base of the Bt horizon: 25 to 50 inches
Depth to calcic horizon: 40 to 60 inches
Thickness of the mollic epipedon: 10 to 16 inches
A horizon:
Hue: 7.5YR or 10YR
Value: 3 or 4
Chroma: 2 or 3
Texture: loam or clay loam
Rock fragments: 0 to 15 percent gravel or cobbles
Reaction: neutral or slightly alkaline
Bt horizon:
Hue: 5YR or 7.5YR
Value: 3 to 6
Chroma: 2 to 4
Texture: loam, clay loam, or sandy clay loam
Rock fragments: 35 to 70 percent mainly gravel or cobbles
Reaction: neutral or slightly alkaline
Bk horizon:
Hue: 7.5YR or 10YR
Value: 5 to 8 (4 to 7 moist)
Chroma: 1 to 4
Rock fragments: 35 to 70 percent, mainly gravel or cobbles
Calcium carbonate equivalent: 15 to 40 percent below 40 inches
Reaction: slightly to strongly alkaline
COMPETING SERIES: These are the Golondrina (NM), Irock (NM), Jumbopeak (NV), Ligai (AZ), Majada (NM), Mokiak (UT), Montoso (NM), Murdo (SD), Nederland (CO), Purcella (NM), Romine (NM), Salas (NM), Wandurn (NM), Wheelerwell (NV) and Willowman (WY) series. Golondrina, and Romine soils do not have a calcic horizon. Majada soils have a calcic horizon within 40 inches. Willowman soils are less than 20 inches to the base of the Bt horizons. Nederland soils have more than 45 percent sand in the particle-size control section. Montoso soils have strongly contrasting layers of cinders between 12 and 32 inches (The concept of Montoso should be reexamined and possibly reclassified as Loamy over pumiceous or cindery). Murdo soils have sola 10 to 20 inches thick over horizons of strongly contrasting sands and gravel (The concept of Murdo should be reexamined and possibly reclassified as Loamy-skeletal over sandy or sandy-skeletal). Irock, Mokiak, and Salas soils are moderately deep to a lithic contact of gneiss or schist bedrock. Jumbopeak soils are moderately deep to a paralithic contact of gneiss and schist. Wandurn soils are deep to a lithic contact of monzonite. Wheelerwell soils are moderately deep to a lithic contact of dolomite.
GEOGRAPHIC SETTING:
Parent material: alluvium derived from mixed sources
Landform: piedmonts, terraces, and fans
Slopes: 0 to 5 percent
Elevation: 5,500 to 7,400 feet
Mean annual temperature: 46 to 52 degrees F
Mean annual precipitation: 13 to 18 inches
Frost-free period: 100 to 180 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Asparas, Plack, and Sampson soils. Asparas and Sampson soils are fine-loamy and are in swales. Plack soils have a petrocalcic horizon and are on the older piedmonts.
DRAINAGE AND PERMEABILITY: well drained, low to high runoff, moderate and moderately slow permeability
USE AND VEGETATION: Purcella soils are used for grazing, wildlife habitat, and wood products. The present vegetation consists of western wheatgrass, sideoats grama, vine- mesquite, pinyon pine, alligator juniper, oneseed juniper, wavyleaf oak, algerita, mountainmahogany, and fourwing
saltbush.
DISTRIBUTION AND EXTENT: Southern New Mexico and Southwest Colorado. LRR D, MLRA 36 and 39. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Lincoln County, New Mexico. 1981.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: The zone from 0 to 12 inches. (A)
Argillic horizon: The zone from 12 to 43 inches. (Bt, Bt2)
Calcic horizon: The zone from 43 to 60 inches. (Bk)
Particle size control section: The zone from 12 to 32 inches. (Bt1, Bt2)
Soil Taxonomy Second Edition, 1999